Every time I'm banging my head against a complex issue with home audio, I inevitably end up on the PS Audio youtube channel. Paul, thank you so much for all of your videos. They have been immensely educational and enlightening.
I also see some advantages of using the "normal" RCA subwoofer output on receivers: - The receiver handles the digital crossover from sub to main speakers (it sends a high pass signal to main speakers, and a low pass signal to the sub). This way you don't have to fiddle around with an analog potentiometer on the sub. - Also, you're guaranteed that the roll-off of the high pass filter and low pass filter match (since these are digitally implemented in the receiver); - Also, you have a degree of freedom: the crossover frequency controlled by the receiver. So you don't have to rely on the high pass behaviour of the main speaker. - The receiver can manipulate the subwoofer signal independently from the main speakers (for example, for LFE effects in movies). Although, when I write this, I realize that the natural roll-off of the main speakers can add an unwanted extra high pass effect (and phase shift) to the main speakers. Likewise, the natural roll-off of the sub at high freq can add an unwanted extra low pass effect (and phase shift) to the subwoofer.
Great points. It definitely makes a lot of sense to use low level in many cases. My understanding is that for a stereo music system the high level input is best at getting the same signal and marrying the sub to your speakers. That said you're totally right and if the subwoofer using a high level input doesn't have an adjustable crossover and gain stage it might be extremely difficult or not possible to get the subwoofer to mesh well with speakers. All totally dependent on what your speakers are capable of range wise. For anyone else reading this - there is at least one company making subs (REL) that ensures not only the proper high level input circuit but also an adjustable crossover and gain of their sub amps. That said it can still be a challenge to dial in any subwoofer this way and also very much depends on your room and speaker/ sub location. Sound science is fun and make sure you enjoy experiments!
Edmonton represent! Great question, I love when Paul gets into circuits. Interesting to see how high level inputs work. Currently saving up for some REL subs.
@@mdaniknightrider REL's Subwoofer Finder suggests the S/510 or dual T/7i. My system is 50/50 stereo/HT. Coming from an SVS sub that digs below 20Hz, I think I will be more satisfied with the S/510.
I was looking at the S/510 too. For the same purpose as you were looking as well. I listened to the S/812 with my speakers at the dealer. Once you hear a REL, there is no way going back subwooferless. It was like the main speakers making that low bass. Incredibly blended via high level, and wirelessly is amazing too. One thing with REL, you can definitely feel that bass in your chest if you have to.
I have had great success using low level inputs for my subwoofers in my room. When I integrate a subwoofer I merely augment the missing lower frequencies. I usually find a placement where the sub bass sounds the strongest from my seating position, then I will adjust the distance from the walls to achieve a smoothest base response possible. Then I adjust the phase until the base sounds like it is coming from the speakers. Next I adjust the frequency and tune the output level to blend with the speakers perfectly. Following this method, the subwoofer sound integrates with my speakers almost perfectly. I find it difficult to understand how adding cables and circuitry would benefit my system.
I have the same success. And if I use high-level I wont get the LFE ch when using surround so. I have a dual mono stereo amp with power amp input (+ 2 sub passthru) and a surround reciver. And I find it's easier to integrate the sub perfect when using low level outputs since I can use delay adjust if the subs phase adjust wont quite get me there.
So how many folks out there have a schematic of the front end of their sub-woofer amp ? In addition the "negative" output of most class-D amps is floating, so you can't connect that to nothing but a speaker. If you are using a single sub-woofer and amp in a center ch configuration the BEST way is to just y-connect the pre-amp out into the low-level (high impedance) sub-in. If you have a "center or sub out" on your preamp or surround processor use it. Most sub-amps "sum" (really an average) the two ch. together as input for the single ch sub-amp. Paul's method works best if your are using a separate sub for each ch. AND your amp output (black-terminal) is tied to ground (aka class A or AB amp). Never use the speaker cable "bypass" connection on the sub-amp itself for reasons mentioned below. It just there for convenience and should be avoided.
Rhythmik either includes HL inputs or offers it as an option on their subs. REL has it in all of their non-HT subs. RSL sells an awesome little ported 10 inch Speedwoofer that includes them. The thing is that most sub makers (REL is an exception) only offer it on their entry level products.
@@billd9667 I think rel made some subs for mj acoustics or the other way around 🤔 anyway their subs with neutrik speakon high level inputs allow you to still retain the .1 data ( lfe ) with the normal rca cable so you get the normal lfe low level stuff like explosions,rumbles ect but with the high level attached you get 5.0 with bass as well if you follow me? So you could be watching a music concert for example and still get bass from your sub even when there is no lfe signal...so you get the best of both worlds! With the mj subs you can put a sub on any channel you want ie fronts,centre and the rears as well .
I agree that high level is best; but how do you mix the .1 LFE channel to the main speakers? I don't see the option to do this with my flagship Denon 8500...?
So im not sure if my vincent sv737 has balanced outputs or a ground, but it has a post B for a second pair of speakers. Can i just use post B to run into my subwoofer?
Hey Paul. I hope you see this I’m with you 100%. Quick question though. Wouldn’t connecting it to the speaker give you the closest sound? That way heaven forbid, the speaker cables add anything to the sound, the sub would pick that up as well. Hope that makes sense.
My sub dissapears perfect when using the RCA.. So that is just an adjustment. And if I hook up to my speaker output I wont get the LFE ch when using surround since I have a combined stereo and surround system.
Dear Paul, regarding high level connections. Do I really have to wire the sub all the way back to the amplifier? Surely I could connect the sub to the speaker terminals if that is the shortage route? I would love to hear your comments. Thank you.
@@Paulmcgowanpsaudio Thank you Paul for your confirmation regarding high level connections. Btw, I am in the proccess of setting up a pair REL T/9i subwoofers with my Quad 57's. My thoughts were that connecting up using the High level inputs rather than the usual low level line inputs was just 'snake oil' promoted by Rel!! But having tried both ways, I have to agree (at least in my case) that intergration and smoothness at the crossover region is better with the high level inputs. My results are based on using REW and a calibrated mic at listening position. Setting up by ear is too hit and miss in my opinion.
Didn't answer a lot for me. What about the other channel. Do we use a mixer to combine L&R line level signals? Do we use something similar for High level signals. Using a "Y" connector on line level outputs of a stereo preamp fails miserably for me as it seems to muddy up the imaging and I'm just talking about the effect that a sub can have on the listening experience. Where you have L and R line level inputs on a sub and use the L and R preamp outputs to feed these, is there some sort of signal mixer in the sub amp circuit? Sorry, too many questions.
I appreciate this explanation. Can you expand on how neutrik cable connections work? I think I also have RCA connections for LFE from my processor/amp to my 2 Rel subs.
If it's not a pure stereo system I recomend RCA (or XLR) since many have combined stereo and surround you will NOT get the LFE channels effect when using surround and using high level input on the sub.. I have a dual mono stereo amp with it's own power amp input and passthru for 2 subs for home cinema use so I can combine both pure stereo and surround. Connecting the sub to the speaker output will ruin the setup. And it's easier to correct for phase when using sub outputs.
Kindly help...car under-seat subwoofer Pioneer TS-WX400DA with built-in amp and accepts high-level input. For speaker level input, do I need a 'High-Low converter'? ...this is because my subwoofer accepts Speaker level input. ....Second, is input from one speaker enough ? or do I have to take input from both speakers to feed the sub .....
Very well explained .. I am a little bit confused highly appreciate it if someone could help me with this...I have just bought Pioneer TS-WX400DA car under-seat subwoofer. It has a built-in amp, a switch for speaker-level input, and two RCA connectors for audio input. I am going to place it under the driver's seat. To power the subwoofer I will battery connection. My car receiver does not have an RCA output. I am planning to take audio input from my front driver-side speaker and split it into two to feed the two input female connectors. Plz help me with the following, am I right or wrong- 1: I guess, I don't need a 'High-Low converter' as my subwoofer accepts Speaker level input. I just need to run two wires from one of the speakers to connect with the subwoofer. 2: .Do I need to take input from both speakers to feed the subwoofer? or input from one speaker is enough...after all both speakers carry the same audio signal ..... Thanks in advance..
Entering spec. into machine learning. All products. Getting back, separates music system recommendations!? Matching different products with machine accuracy or recommending product specs!? But, what about listening pleasure!? Any AI there!? Thank you.
Hi please advice I looking for a active sub for my powered mackie crx4 monitors do I need special studio sub ? Can I use any sub ? What output required please ......jan united kingdom
If my subwoofer doesnt have high level Inputs, is it possible to use a high Level to low Level converter, to get the Signal right for the Low Level Inputs of my subwoofer ?
so our amplifiers must have negative - grounded otherwise if we use high level input of a sub, we can cook our main amplifier? did i get it correct? how the hell we can know if the amp in our hand has negative (black terminal) grounded?
I am running a music only, 2-channel HiFi system that uses a Vincent SA-31 MK preamplifier and a Vincent SP-331 power amplifier. SVS recommended the SB-1000 Pro subwoofer for my speaker and room size. Will I get better sound quality by: using the RCA connections and putting this sub between the preamp and amp ( Preamp -> Sub -> Power Amp -> Speakers ) OR using speaker cables utilizing the high-level speaker wire inputs on the sub ( Preamp -> Power Amp -> Sub -> Speakers ) ? Thank you in advance for your recommendations.
Great video , you lost me 1 min into it, it’s okay that’s on me, not the brightest, hence my question: I have your Sprout100, (loving it!), wanted to add a REL T9X and they say to connect it via high level output, .. how do I do that (if at all)? The sprout has the sub out, but from what little I got out of this video is that I shouldn’t use that because it connects to the “low level” , and what I have to do (I think) is somehow cut the cables going into the speakers and somehow plug that into their high level .. but then you mentioned something about this shorting out the system.. Brain hurts, please help. I’m all seriousness tho I really like your Sprout100 and really want to make it work with the REL T9X through their (and your) recommended “high output” connection; can I do that and if so how ? (With lots of details please, I’m really far behind on this). Thank you and have a wonderful day.
Okay Rel I’ve sent a request thru your actual site to combat the hum in my T5x stereo pair hooked up via high level to my Bat VK-75se with no response. I floated the black wire. I connect the black to chassis ground on my bat preamp. I’ve hooked up rca connectors to LFE on the sub to the preamp unused connectors. Hum persists. What is the solution?
I have my Subwoofer hooked to the B-speaker outputs on my integrated amp (and the speakers hooked to the A-speaker. And running them both at the same time, would this be bad in any way?
@@Taffy84 Yeah I figure its much shorter and less disrupted signal path between the amp and the speakers. And that the sub isnt actually commanding any current, so shouldnt be much of a problem for the amp? I just dont know if it affects the impedance seen by the amp?
i have this on my mind,. how about i put a 1 Y rca to my 1 of L/R pre out,. from (right pre out channel for example) to my subs LFE, and to power amp that powers the speaker,. do you think this will make any harm to my denon x3700h?
I am confused. I have a BHK 250 amp which has four pairs of speaker outputs. Two pair are connected to my speakers. Can I not use the other two pair and connect them to the high level inputs on a subwoofer and be OK? If not, what do I do?
Just the video that I needed as well as I await delivery of a Pioneer sub (Adam Jones design) and a Def Tech sub. Until now I have used dual voice coil 10 and 12-inch passive.
i have a problem with my sub and high level inputs. My receiver is old and doesnt have pre out or sub out. When connected (via speaker A or B) my SUB remains always On (it has an auto of capability) and has a boomy sound, even when my amp is OFF! Any idea why ?
What receiver? What sub? Too general of a question to know what the variables would be. Don't expect quality bass out of a $100 sub. If it was $1000, then I would expect some slammin' bass.
@@zulumax1 its a vintage receiver Marantz 2216. My sub is an elax with High level in. My problem is that even i shut down my AMP , there is a sound (Buzz/boom) from my SUB !
@Lloyd Stout Ground loop, that is my diagnosis too. Try a ground lifter first, that is the easiest fix if the sub has a 3 prong plug. Older vintage equipment, especially the non polarized type can cause wreck havoc with modern grounded equipment working together. Also can try reversing the non polarized type plug on the amp into the wall.
Elac sub? Which model? If your sub has a 3 prong grounded plug you could be getting a ground loop hum between the sub and amp. If so try a 3 to 2 prong adaptor called a "cheater" or "ground lifter"and leave the ground wire unconnected to ground on the subwoofer.
I just purchased a Yamaha Model:R-S202BL and have not hooked it up yet. I do not know if it has balanced or grounded speaker outputs. I will be adding a monoprice 12" subwoofer and I do not know if it has grounded negative high inputs. Can I simply use a multimeter to see if the receiver high outputs black negatives have continuity to chassis ground? And, can I see if the subwoofer high inputs black negatives also have continuity to chassis ground? I know this equipment is not overly great or expensive and is just for a reasonable shop stereo. I just do not want to screw it up on installation. Blessings if anyone answers.
won't it have a negative side-effect on the poweramp now ? won't it influence the sound that is produced by the main speakers because the amp not only drives two front speakers but also the subwoofers amp ? (i have a denon av-receiver with pre outs to a denon poa-2600 power amp for the front speakers. i don't feel comfortable driving the sub-amp by this power amp so i use the sub-amp for filtering, with sub-amp connected to the sub-out of my av-receiver . The av-receiver drives no front speakers, but it powers the surrounds and center in case of watching a movie )
Hi, I appreciate this information. I'm connecting my system today. I agree with your stance on using the high level inputs. I'll be connecting a vintage Harman Kardon 330C to a powered sub via the high level inputs on the sub. The 330C features 2 channels, "speakers 1" and "speakers 2." There's a separate pushbutton on/off switch for each. I already have "speakers 1" connected to a set of towers, so if I connect "speakers 2" to the high level inputs on the sub, I won't have any concerns or cautions like you were discussing with the grounding out of a bridged channel or anything, correct? Thank you.
Hello Paul...hello youtubers...question? Does anyone know if the high level Neutrik speakon connection plug (sub end) are all the same ie are mj acoustics..rel..mk all the same type of plug.? I can purchase the high level lead from a company online and they sell the rel high level Neutrik speakon lead (3 wires) problem is I have a mj acoustics subwoofer and they are not sure if there cable will work with the mj acoustic subwoofer? The rel lead is considerably cheaper than the mj acoustics lead and as such would like to buy the rel one to allow that saving...how can I find out? Is the pole/pin configuration different between the 2 ie 2 pole,3 pole and 4 pole ect? Nobody seems to know the answer! Any help would be appreciated.
@@mikecampbell5856 Mike can you help me out I am new to this when you using your amplifier high level on your subwoofer which one is basically the best volume to use the preamp on your receiver sub out to turn it up or just leave it down and turn the volume with the amplifier from your subwoofer high level to blend in speakers thank you
@@petercollie9251 Hi, when using the high level (speaker level) input and output terminals on your sub, set the crossover to about 100hz, play some tunes and turn up the sub volume level until it becomes noticeable then back it off a bit. When using the RCA sub out on your receiver, all you have to do is set it to a level that sounds good to you, the internal crossover on the receiver will take care of the levels for the most part. Use the line or LFE input. Some subs have a L and R input. Use the L. Check out the menu for your receiver if it is a surround receiver. You can set crossover frequencies and levels with your remote and customize your sound. You can have a blast doing this.
So I just learned that all subs are grounded so I can’t connect my amp on high level inputs without short it. So that didn’t answer my question at all because that don’t make sense. What I really wanted to know is how connecting the sub on high level input affects the impedance on the amp because my speakers are 4ohms and I don’t want to go lower with the risk on breaking it.
I know this comment is a yr old lol, but both the high & low input’s are attenuated in the pre-amp stage in your amp & do not affect the output (power rated) section which includes the ohm rating. So it wouldn’t hurt it. The power rated section (amp output) is what you match by the wiring configuration of your subs, which cant go below amp’s ohm rating or the amp will pass much more current through that path which lacks the rated resistance, likely frying the amps power output sections. The high level input would have nothing to do with that situation though, as all hi-in is doing is telling the amp to knock off some gain sensitivity so there’s no input clipping.
Hi Paul. Merry Christmas to you and your family. Your explanation really threw me on this one. I also use the high-level inputs on my sub from my Power Amplifier, but l then use the high-level output of the sub to my speakers. I would have thought that would be the correct way? Am I missing something? Keep up the great work. 👍
If you go the first route, what’s a good level to set the high level at or do you just play it by ear so to speak? Btw, is this the same as High Cut? My Yamaha YST has both High Cut and Volume controls... Happy Christmas to all at PS Audio and thanks for your videos during these awful times! ✌️💕🇦🇺
Thanx for sharing. I,m trying to connect from an avr high level out (tapping center sp out) to a subwoofer low level in terminal. is it safe to do? I already run pout of subs out. Using 4 rels for LFE, but I like to create rel 3D by adding 3 more subs to 1:mains, 1 to Center, 1 to surround. I have extra subs I can use but they only have line in or LFE available no high level in. perhaps using a high level in line out converter solves this? Anybody?
If both of your amp terminals are hot, like in a balanced differential amp, you cannot connect to the ground terminal of a REL sub to the amp terminal. Instead you only connect the hot terminal of the sub to the positive terminal of the amp and you need to connect the ground terminal of the sub to a true ground on the amp. That could be the phono ground post or, better, the return of an unused RCA connection on the amp or any other connected component for that matter. The REL sub just needs to find a true ground reference. No idea about the B+Ws.
You can connect an active Rel sub with high level connection to virtually any amp but the method of grounding will vary depending on the amp. The issue arises because you are really connecting an amp to your amp output, not a passive speaker. Having a single pair or two pairs of speaker posts on the amp is irrelevant. These are usually connected in parallel and are there just for connection convenience, instead of trying to connect multiple wires to a single post.
Im not an expert but If the problem is that you could short the negative amp to grund why do you even use it? You could youse the subwoofer it self as the black chanel
High-level inputs to a sub sounds wonderful on paper. But the theory only works if the sub amp has no sonic signature of its own - which every amp does. There are other reasons to avoid high-level input but this reason alone should squash the desire to do so. Besides that, the sub's signal is now passing thru 2 amps rather than 1 amp which at least theorically could induce time delays. And in the case of the REL subs, one is forced to use REL high-level cables which of course will also induce their own sonic signature and hence most likely with be different than the speaker cables' sonic signature. So it seems to me that those who boast about the supposedly superior sonic benefits of high-level inputs are relying more on what they read and imagine rather than what they actually hear. Because based on the above (and more) high-level inputs should actually cause greater differences, more distortions, and potentially more time delays than low-level inputs. What were they possibly thinking (or smoking) when conceiving the idea of high-level inputs?
And, how can you relieve your mains with a high pass filter??? Does this mean that putting filters into the speaker signal is preferable to filtering the line level signal??
@@Hikebike365 Based on what I stated earlier, I suspect it means, what were they possibly thinking when deciding to go the high-level input route? The experts claim we would get the main amp's sonic signature carried by high-level inputs to the sub and indeed it may. But at what cost? Doesn't really matter because the sub amps have their own sonic signature so their theory is already blown to hell not to mention all the other sonic baggage high-level inputs bring to the table. An additional and very important point I neglected to mention earlier was, with every component the input signal is further degraded which implies the high-level input signal at the sub is now more compromised because it passed thru two amps insteand of 1 amp. Seriously, what in the world were they thinking? Fundamentally, it seems to me the easiest most efficient, and greatest sonic benefits implies staying with low-level inputs. It can work rather well. For example. th-cam.com/video/tNh-aFORuZ8/w-d-xo.html
Making the sub parallel to the main speaker means a relatively wide area where the sub and the main speaker overlap. That creates and interesting mushy phase mix of lowish frequencies that might completely overshadow the character of the single power amp that you want to preserve. Tell me why this is not a problem.
@Art DIY In the configuration that Paul suggests, the main speaker gets all frequencies, including frequencies close to its lower capability. That means that the main speaker will have considerable phase and magnitude characteristics there. Without a sub this is not a problem, as we are not _very_ sensitive for phase. But with a sub we add a driver in the same frequency area _with a different phase characteristic._ Depending on the main speaker enclosure and driver type, we get an interesting, frequency-dependent phase-and magnitude mix, which could lead to very loud or suppressed frequencies or less clarity (less tight). This all depends on the sub-position, of course. You cannot fix this with a simple phase-knob unless it knows the type of the main speaker. But maybe there is a trick I don't know that makes such a knob okay. In short: it is very difficult to get a nice characteristic and adding a phase knob might also alter the character of the lot. To avoid phase and magnitude problems, we should minimize the overlap in frequencies and make the switch at a frequency that both speakers can reproduce comfortable. But that means a crossover, which is not the configuration that this video is about. And naturally, this adds even more character to the signal than the main amp (I might hope). Another discussion is whether a lot of "character" is added below 100Hz that cannot be reproduced with an equalizer. Does it matter? Or is it that second-order harmonic distortion that is so beautiful? But then we are talking about beautifying sound instead of reproducing it with high fidelity. This is a matter of taste. In studio equipment, crossover is almost always done at low signal level or even in the digital domain. A power amplifier for each frequency range drives the speaker directly, so it has tight control over it. This gives you _accurate_ sound reproduction. A warm recording will sound warm, a sterile recording sterile and a bad recording, unfortunately the majority, horrible. You can literally hear the limiter "rattle" in a lot of modern "loud" recordings.
@Art DIY if the combination works: please enjoy it! I'm merely saying that from a technical standpoint, the success of Paul's suggestion is very dependent on specific combinations of equipment. This is why I would personally not advise it as _a general solution._
When I could compare, the high level input does indeed sound better and I would use that if possible. If all I had was the low level I would use that without concern, the difference is not huge on any of the subs I have tried.
Good afternoon paul my name is David. Y wish please if you that explanation to conect high level input to a subwoofer with the real sibs and speakers . Y hope to see you in the next video
so you do not loose some sub channel information from 5.1 movies with 5.0 on av receiver and high channel input on sub from front speaker output? As I understand, the movie .1 channel has +10 db and in a 5.0 config the av receiver would downmix this +10 db lfe signal so you would loose probably some movie bass + the .1 channel mixed from my amp into the front speakers would end in my sub + front speakers at the end, probably not a big issue... so for 5.1 movies and a yamaha RX-v685 + Canton Ergo AS 650 SC Sub, is high level input still a good choice?
@Lloyd Stout oh lol thats not in my budget, I spend every month half of my 8h/week student job payment on tech from ebay... but the yamaha v685 ypao setup might do a ok job and I will check what I like more, yes... atm my music on the Canton ergo 670 dc fronts with 1x180mm woofer could have more punch with my canton ergo as 650 sc subwoofer
I use the high level inputs on my two channel music systems and the low level input on my home theater. I never listen to music on my home theater system.
Problem is that most subwoofers have a crap circuit built into the high and low pass on speaker level inputs. Most subs just use one garbage electrolytic cap feeding the high pass. I have read from crossover gurus this creates response problems in the stereo speakers passive crossover.
@Lloyd Stout Garbage advice. There is a reason that the venerated REL now offers an LFE input option. Because it's better. -✌🏼 A simple search for the top subwoofers of a given year affords a myriad of options for the buyer.
@Lloyd Stout Crazy Paul included theater along with two channel in his stirring white board dissertation. As if they are intertwined. He's so far removed from the everyday user it's comical. And just for the record, my processor plays two channel with four subwoofers using LFE as good as any system I've ever heard.
Wait do i get that right now... u basically take just the sound signal, from, say ur main speaker channel, so u double plug the main channel and run one pair cables to the speaker and one pair cables to the high lvl input on the sub? Or did i Literally got it all wrong?😂
i have my amp to elac sub to high level ins. works well with blended crossovers. with low level rca in if u use intergrated amp. some cannot control volume of subwoofer. need preamp .either active with power amp. or passive with intergrated. or adjust vol. of sub. to blend with speakers. both can activate different sound signature.
Most AV systems have a setting for big speakers or small speakers where the bass frequencies are NOT sent to small speakers so that they can play louder without woofer cone breakup and the bass is sent to the subwoofer via the LFE output. in this case a high level input won't work. Also my sub has a low level input (from your preamp out) and out that would go to the power amp can be low frequency limited for the same reason as most AV systems.
Hi, PS Audio Why some company set parameter in Voltage of limiter setting and some company in dB ? May be dB is better to understand than Voltage. Please explan
This is just silly -- we're talking about a very low-pitched octave or so, an octave that has no audible "sonic signature" to speak of. Even if you don't believe that, do things Paul's "proper" way and whatever little "sonic siqnature" the power amp has down at the low end of the audio spectrum will be *added* to whatever "sonic signature" the sub's amp has -- IOW, Paul's recommendation presumes that the subwoofer has a perfectly transparent power amp, which is more than a little naive. The character or timbre of a bass note comes from the mid-bass range, not that lowest octave or so, thus it's your L+R speakers that deliver the difference between an acoustic bass note and an organ pedal bass note, not the subwoofer. IMO, you'll be doing yourself a favor by driving your active sub via the same preamp outputs that drive your power amp, using a couple of simple Y-adapters if necessary. My sub does have "proper" high-level inputs, BTW -- and as far as my ear can tell using them confers no audible advantage whatsoever.
Having the side speakers trying to do the bass that you bought a subwoofer to do better is not always a good idea if you want the highest quality deep bass.
One would think so, but one would be incorrect. Speakers, unless they are designed as limited range satellites, are designed to take the full signal. By adding the sub you are really augmenting the speakers for the low frequencies that they cannot produce adequately. For example, in case main speakers are 2 way, what you create by adding subs is a 2.5 way speaker.
@@razisn Of course stereo speakers are designed to take the full signal but it doesn’t mean they perform well in the deepest bass. Usually smaller speakers are using tricks to produce deeper bass that yield poor decay performance and a distortion that can become multiple percent at higher volumes. Your low distortion subwoofer might produce a very clean 50Hz that then combines with some smaller stereo speakers outputting 20% THD on top of it. A smaller woofer of your stereo speakers will hit the excursion limits much earlier creating compression distortion and some smaller speakers also make much port noise. A major benefit of high-pass filtering the side speakers is that your power amp can use the power focused on what the side speakers are better at. But of course adding high-pass filtering to your side speakers is best done on the line level or in a DSP before your audio hits the DACs and power amps. My favorite approach is using DSP where you can do much better optimization of frequency response and phase (e.g. using miniDSP).
If your system is for Home Theater and balanced, the balanced connection to the subwoofer is better. I can see this being more applicable to an audio only system. Going from a single ended connection on a subwoofer to a balanced, there is a very noticeable difference. The subwoofer plays deeper and louder.
Its not difficult. Let's break it down. Question: Is the high impedance input simply directed through a high value resistor? Answer: It IS a simple resistive divider in many subwoofers; but, that creates a problem for balanced amplifier outputs since the inverted output would be shorted to ground in the subwoofer. Addendum: The solution to that, for subwoofer designers, is to take both inputs through the resistive dividers into a differential amplifier. Then both sides of the connections would go through high impedance resistors, thus allowing it to work for both balanced and unbalanced amplifier outputs.
@@timharig ok, so this video is for a designer of the circuit to allow that the sub to utilize the speakers output? I didn't understand when he said that the sub wouldn't draw watts from the power amp just the signal? lol.. this reminds me of algebra...
@@yrulooknatme Well no. You do need to know this when attaching your subwoofer this way. If you have a balanced amplifier output you could short and damage your system if the subwoofer isn't designed to handle the balanced inputs. Then he describes how the designer should handle that balanced inputs which you do not need to fully understand as a user. You are going to a have a very difficult time in this hobby if you do not understand some basic mathematics and some basic electrical rules. Understanding this video requires understanding voltage and current dividers. When impedances are wired in series, the current going through them is is the same; but, the voltage is divided across each impedance in proportion to its impedance the total impedance. When impedances are wired in parallel the voltage across them is the same but the current is divided between them inversely proportional to each's impedance compared to the total impedance. In this connect, the subwoofer is in wired in parallel with the speaker. So the voltages across them are the same but the current is divided between them. Because the speaker's impedance is only a few ohms compared to the subwoofer's impedance which is on the order of kilo-ohms, very little of current is siphoned off of the speaker's line. If the speaker impedance is 8ohm and the subwoofer impedance is 100k ohm, then the subwoofer is only drawing about 0.0008% of the speaker's current. Then in the subwoofer, that small amount of current travels through two resistors in series to divide the voltage to a level appropriate for the subwoofers amplifier to handle.
@@timharig thanks I'll keep reading this till it starts to sink in a little... I never got into active subwoofers and surround sound systems. always had stereo with woofer and tweeter and sometime mids. To me this sounds like a better way to utilize a sub. if you had one. I've always wondered what a bridged amp was and now I know. sure don't want to run that to ground. thank you
Sounds like gibberish. A PS Audio customer for many years: Want to connect two REL subwoofers to two balanced amplifiers. This video does not help at all. Am I supposed to go out and buy 100K resistors?? This video just create confusion. Is there a concrete and simple way how to connect the subwoofers?
High level inputs should be differential indeed as Paul explaines. Works universally. Crap circuits like REL's where you have to connect somewhere to the chassis although nothing is provided for that is a solution not matching all real world situations. And it is costing pennies at most indeed as Paul says to implement it well. Suggests REL lacks the proper engineering skills or mayby just buys cheaply from China. (I have a REL and found difficulty connecting it with my Pioneer Kuro: RCA had a hum due to a grounding loop, high level speaker output balanced)
Sorry, but that comment is just a big steaming load of "REL bashing" horse sh!t... At best it sounds like you bought a product you clearly have no idea how to PROPERLY use-for Christ sakes, you hooked your sub up directly to your "plasma TV" which is about the SHITTIEST hit/miss connection scenario imaginable for performance since the audio output stages in all those Plasma TV's were utter "lowest common denominator" garbage to begin with (talk about using cheesy "Crap Circuits"!) and you're wondering why you are having "difficulty" with performance and grounding issues with your sub?🙄 Seriously? That’s called “User Error” dude, BUY A "REAL" STEREO/AV RECIEVER OF DECENT QUALITY AND YOU WON'T HAVE NOISE AND GROUNDING ISSUES ANYMORE! What you're doing right now is the equivalent of someone buying a high performance sportscar then putting shitty cheap ass tires and brakes on it, using the lowest grade fuel and oil they can possibly buy and then getting online afterwards to ignorantly complain about the performance of their car like it's supposed to somehow miraculously turn shit into sugar... I have used REL subs in multiple systems for over 20 years "without" issues (I just recently upgraded to S812's in one of my systems after listening to numerous competitor subs just to see if there were any other potential contenders to the throne so to speak) and have yet to hear any sub outperform the REL’s in a real world situation "when" connected and dialed in correctly. BTW: You ARE aware that Paul himself uses REL's in his own home system and recommends them, right?
TL:DR ALWAYS SET YOUR SPEAKERS AS SMALL IN BASS MANAGEMENT AND USE THE LFE INPUT OF YOUR SUBWOOFER AND MAX ITS CROSSOVER IN ORDER TO USE THE ACTIVE CROSSOVER OF YOUR PROCESSOR AND GET THE MOST ACCURATE BASS REPRODUCTION IN CONJUNCTION WITH YOUR MIDS AND HIGHS. or take the word of a guy who cannot recall a name from two minutes ago who is stuck in the dark ages of modern audio tech. 😊
Thank you, mr. troll, for screeching at the top of your verbal lungs at us the exactly *incorrect* way of doing things, while rudely getting in another jibe at our gracious host. Well done.
That’s dumb just come out of your pre amp to the subs, come out from balance output too lfe or if your subs have a balance input 🥴this is so stupid to do and old fashioned the way Paul is saying
Every time I'm banging my head against a complex issue with home audio, I inevitably end up on the PS Audio youtube channel. Paul, thank you so much for all of your videos. They have been immensely educational and enlightening.
Yes to hi level inputs, much better integration of sound👍
I also see some advantages of using the "normal" RCA subwoofer output on receivers:
- The receiver handles the digital crossover from sub to main speakers (it sends a high pass signal to main speakers, and a low pass signal to the sub). This way you don't have to fiddle around with an analog potentiometer on the sub.
- Also, you're guaranteed that the roll-off of the high pass filter and low pass filter match (since these are digitally implemented in the receiver);
- Also, you have a degree of freedom: the crossover frequency controlled by the receiver. So you don't have to rely on the high pass behaviour of the main speaker.
- The receiver can manipulate the subwoofer signal independently from the main speakers (for example, for LFE effects in movies).
Although, when I write this, I realize that the natural roll-off of the main speakers can add an unwanted extra high pass effect (and phase shift) to the main speakers. Likewise, the natural roll-off of the sub at high freq can add an unwanted extra low pass effect (and phase shift) to the subwoofer.
Great points.
It definitely makes a lot of sense to use low level in many cases. My understanding is that for a stereo music system the high level input is best at getting the same signal and marrying the sub to your speakers.
That said you're totally right and if the subwoofer using a high level input doesn't have an adjustable crossover and gain stage it might be extremely difficult or not possible to get the subwoofer to mesh well with speakers. All totally dependent on what your speakers are capable of range wise.
For anyone else reading this - there is at least one company making subs (REL) that ensures not only the proper high level input circuit but also an adjustable crossover and gain of their sub amps. That said it can still be a challenge to dial in any subwoofer this way and also very much depends on your room and speaker/ sub location. Sound science is fun and make sure you enjoy experiments!
Edmonton represent!
Great question, I love when Paul gets into circuits. Interesting to see how high level inputs work. Currently saving up for some REL subs.
Same here 🤭 Which model are you looking at to buy?
@@mdaniknightrider REL's Subwoofer Finder suggests the S/510 or dual T/7i. My system is 50/50 stereo/HT. Coming from an SVS sub that digs below 20Hz, I think I will be more satisfied with the S/510.
I was looking at the S/510 too. For the same purpose as you were looking as well. I listened to the S/812 with my speakers at the dealer. Once you hear a REL, there is no way going back subwooferless. It was like the main speakers making that low bass. Incredibly blended via high level, and wirelessly is amazing too. One thing with REL, you can definitely feel that bass in your chest if you have to.
I have had great success using low level inputs for my subwoofers in my room. When I integrate a subwoofer I merely augment the missing lower frequencies. I usually find a placement where the sub bass sounds the strongest from my seating position, then I will adjust the distance from the walls to achieve a smoothest base response possible. Then I adjust the phase until the base sounds like it is coming from the speakers. Next I adjust the frequency and tune the output level to blend with the speakers perfectly. Following this method, the subwoofer sound integrates with my speakers almost perfectly. I find it difficult to understand how adding cables and circuitry would benefit my system.
I have the same success. And if I use high-level I wont get the LFE ch when using surround so. I have a dual mono stereo amp with power amp input (+ 2 sub passthru) and a surround reciver. And I find it's easier to integrate the sub perfect when using low level outputs since I can use delay adjust if the subs phase adjust wont quite get me there.
Yup, same here
Surround movies sound better with LFE, music sounds way better with high level, especially if you have 2 subwoofers.
Merry xmas to you and your family and everyone at PS Audio.
What Paul is doodling on the whiteboard reminds me of a subwoofer hum eliminator box that was usually sold in car stereo shops back in the 1990s.
Great video and explanation. So many views i'm surprised there aren't heaps more likes!
So how many folks out there have a schematic of the front end of their sub-woofer amp ? In addition the "negative" output of most class-D amps is floating, so you can't connect that to nothing but a speaker. If you are using a single sub-woofer and amp in a center ch configuration the BEST way is to just y-connect the pre-amp out into the low-level (high impedance) sub-in. If you have a "center or sub out" on your preamp or surround processor use it. Most sub-amps "sum" (really an average) the two ch. together as input for the single ch sub-amp. Paul's method works best if your are using a separate sub for each ch. AND your amp output (black-terminal) is tied to ground (aka class A or AB amp). Never use the speaker cable "bypass" connection on the sub-amp itself for reasons mentioned below. It just there for convenience and should be avoided.
Just the video I needed. Now to find a high level sub.
Rhythmik either includes HL inputs or offers it as an option on their subs. REL has it in all of their non-HT subs. RSL sells an awesome little ported 10 inch Speedwoofer that includes them.
The thing is that most sub makers (REL is an exception) only offer it on their entry level products.
Mj acoustics do high level
@@richardcoles2432 MJC is not a household name in the states, though REL is
@@billd9667 I think rel made some subs for mj acoustics or the other way around 🤔 anyway their subs with neutrik speakon high level inputs allow you to still retain the .1 data ( lfe ) with the normal rca cable so you get the normal lfe low level stuff like explosions,rumbles ect but with the high level attached you get 5.0 with bass as well if you follow me? So you could be watching a music concert for example and still get bass from your sub even when there is no lfe signal...so you get the best of both worlds! With the mj subs you can put a sub on any channel you want ie fronts,centre and the rears as well .
Wooo! Edmonton represent! 👋
I agree that high level is best; but how do you mix the .1 LFE channel to the main speakers? I don't see the option to do this with my flagship Denon 8500...?
So im not sure if my vincent sv737 has balanced outputs or a ground, but it has a post B for a second pair of speakers. Can i just use post B to run into my subwoofer?
Hey Paul. I hope you see this I’m with you 100%. Quick question though. Wouldn’t connecting it to the speaker give you the closest sound? That way heaven forbid, the speaker cables add anything to the sound, the sub would pick that up as well. Hope that makes sense.
Only way I hook up my subs since discovering this option. My two subs “disappeared” configured this way. I’ll never go back.
My sub dissapears perfect when using the RCA.. So that is just an adjustment.
And if I hook up to my speaker output I wont get the LFE ch when using surround since I have a combined stereo and surround system.
both your subs are connected via the high level? can you explain?
@@zatara5299 Left to left one the left sub and right to right on the right one.
So in this case, it's ok for all type of amplifier ?
What if the powered subwoofer doesn't have a high level input? Would a high to low level converter work the same?
Dear Paul, regarding high level connections. Do I really have to wire the sub all the way back to the amplifier? Surely I could connect the sub to the speaker terminals if that is the shortage route? I would love to hear your comments. Thank you.
Yes, absolutely you can do that and that's the easiest way to do it.
@@Paulmcgowanpsaudio Thank you Paul for your confirmation regarding high level connections. Btw, I am in the proccess of setting up a pair REL T/9i subwoofers with my Quad 57's. My thoughts were that connecting up using the High level inputs rather than the usual low level line inputs was just 'snake oil' promoted by Rel!! But having tried both ways, I have to agree (at least in my case) that intergration and smoothness at the crossover region is better with the high level inputs. My results are based on using REW and a calibrated mic at listening position. Setting up by ear is too hit and miss in my opinion.
Didn't answer a lot for me. What about the other channel. Do we use a mixer to combine L&R line level signals? Do we use something similar for High level signals. Using a "Y" connector on line level outputs of a stereo preamp fails miserably for me as it seems to muddy up the imaging and I'm just talking about the effect that a sub can have on the listening experience. Where you have L and R line level inputs on a sub and use the L and R preamp outputs to feed these, is there some sort of signal mixer in the sub amp circuit? Sorry, too many questions.
I appreciate this explanation. Can you expand on how neutrik cable connections work? I think I also have RCA connections for LFE from my processor/amp to my 2 Rel subs.
Should I tap off both left and right channel?
If it's not a pure stereo system I recomend RCA (or XLR) since many have combined stereo and surround you will NOT get the LFE channels effect when using surround and using high level input on the sub.. I have a dual mono stereo amp with it's own power amp input and passthru for 2 subs for home cinema use so I can combine both pure stereo and surround. Connecting the sub to the speaker output will ruin the setup. And it's easier to correct for phase when using sub outputs.
Kindly help...car under-seat subwoofer Pioneer TS-WX400DA with built-in amp and accepts high-level input. For speaker level input, do I need a 'High-Low converter'? ...this is because my subwoofer accepts Speaker level input. ....Second, is input from one speaker enough ? or do I have to take input from both speakers to feed the sub .....
Sir is it possible to connect parallel my yamaha rxa1020 receiver the front speaker to high input of subwoofer
Very well explained .. I am a little bit confused highly appreciate it if someone could help me with this...I have just bought Pioneer TS-WX400DA car under-seat subwoofer. It has a built-in amp, a switch for speaker-level input, and two RCA connectors for audio input. I am going to place it under the driver's seat. To power the subwoofer I will battery connection. My car receiver does not have an RCA output.
I am planning to take audio input from my front driver-side speaker and split it into two to feed the two input female connectors. Plz help me with the following, am I right or wrong-
1: I guess, I don't need a 'High-Low converter' as my subwoofer accepts Speaker level input. I just need to run two wires from one of the speakers to connect with the subwoofer.
2: .Do I need to take input from both speakers to feed the subwoofer? or input from one speaker is enough...after all both speakers carry the same audio signal .....
Thanks in advance..
Entering spec. into machine learning. All products. Getting back, separates music system recommendations!? Matching different products with machine accuracy or recommending product specs!? But, what about listening pleasure!? Any AI there!? Thank you.
How do I know if my Krell’s S-300i speaker output is balanced or unbalanced? I can’t find that information in the owners manual.
Hi please advice I looking for a active sub for my powered mackie crx4 monitors do I need special studio sub ? Can I use any sub ? What output required please
......jan united kingdom
If my subwoofer doesnt have high level Inputs, is it possible to use a high Level to low Level converter, to get the Signal right for the Low Level Inputs of my subwoofer ?
so our amplifiers must have negative - grounded otherwise if we use high level input of a sub, we can cook our main amplifier? did i get it correct? how the hell we can know if the amp in our hand has negative (black terminal) grounded?
I am running a music only, 2-channel HiFi system that uses a Vincent SA-31 MK preamplifier and a Vincent SP-331 power amplifier. SVS recommended the SB-1000 Pro subwoofer for my speaker and room size. Will I get better sound quality by: using the RCA connections and putting this sub between the preamp and amp ( Preamp -> Sub -> Power Amp -> Speakers ) OR using speaker cables utilizing the high-level speaker wire inputs on the sub ( Preamp -> Power Amp -> Sub -> Speakers ) ? Thank you in advance for your recommendations.
Great video , you lost me 1 min into it, it’s okay that’s on me, not the brightest, hence my question:
I have your Sprout100, (loving it!), wanted to add a REL T9X and they say to connect it via high level output, .. how do I do that (if at all)? The sprout has the sub out, but from what little I got out of this video is that I shouldn’t use that because it connects to the “low level” , and what I have to do (I think) is somehow cut the cables going into the speakers and somehow plug that into their high level .. but then you mentioned something about this shorting out the system..
Brain hurts, please help.
I’m all seriousness tho I really like your Sprout100 and really want to make it work with the REL T9X through their (and your) recommended “high output” connection; can I do that and if so how ? (With lots of details please, I’m really far behind on this).
Thank you and have a wonderful day.
Okay Rel
I’ve sent a request thru your actual site to combat the hum in my T5x stereo pair hooked up via high level to my Bat VK-75se with no response.
I floated the black wire. I connect the black to chassis ground on my bat preamp. I’ve hooked up rca connectors to LFE on the sub to the preamp unused connectors. Hum persists. What is the solution?
I have my Subwoofer hooked to the B-speaker outputs on my integrated amp (and the speakers hooked to the A-speaker. And running them both at the same time, would this be bad in any way?
No, I've seen people recommend you do it that way if you have A+B.
@@Taffy84 Yeah I figure its much shorter and less disrupted signal path between the amp and the speakers. And that the sub isnt actually commanding any current, so shouldnt be much of a problem for the amp? I just dont know if it affects the impedance seen by the amp?
@Lloyd Stout Are you sure? Maybe it is dividing power per usage? So if B channel is not using any current, all current will go to the A channel?
i have this on my mind,. how about i put a 1 Y rca to my 1 of L/R pre out,. from (right pre out channel for example) to my subs LFE, and to power amp that powers the speaker,.
do you think this will make any harm to my denon x3700h?
Good morning Paul
If the subwoofer is setup for balanced input,as Paul shows in diagram, can it be driven by amplifier output with the grounded black speaker output?
I am confused. I have a BHK 250 amp which has four pairs of speaker outputs. Two pair are connected to my speakers. Can I not use the other two pair and connect them to the high level inputs on a subwoofer and be OK? If not, what do I do?
Actually you can indeed use the second set of ouputs. Paul confirms this in the vid.
Just the video that I needed as well as I await delivery of a Pioneer sub (Adam Jones design) and a Def Tech sub. Until now I have used dual voice coil 10 and 12-inch passive.
i have a problem with my sub and high level inputs.
My receiver is old and doesnt have pre out or sub out.
When connected (via speaker A or B) my SUB remains always On (it has an auto of capability) and has a boomy sound, even when my amp is OFF!
Any idea why ?
What receiver? What sub? Too general of a question to know what the variables would be. Don't expect quality bass out of a $100 sub. If it was $1000, then I would expect some slammin' bass.
@@zulumax1 its a vintage receiver Marantz 2216. My sub is an elax with High level in. My problem is that even i shut down my AMP , there is a sound (Buzz/boom) from my SUB !
@Lloyd Stout Ground loop, that is my diagnosis too. Try a ground lifter first, that is the easiest fix if the sub has a 3 prong plug. Older vintage equipment, especially the non polarized type can cause wreck havoc with modern grounded equipment working together. Also can try reversing the non polarized type plug on the amp into the wall.
Elac sub? Which model? If your sub has a 3 prong grounded plug you could be getting a ground loop hum between the sub and amp. If so try a 3 to 2 prong adaptor called a "cheater" or "ground lifter"and leave the ground wire unconnected to ground on the subwoofer.
Also try unplugging the amp, reversing the plug, and plugging it back in and see if the buzz goes away.
I just purchased a Yamaha Model:R-S202BL and have not hooked it up yet. I do not know if it has balanced or grounded speaker outputs. I will be adding a monoprice 12" subwoofer and I do not know if it has grounded negative high inputs. Can I simply use a multimeter to see if the receiver high outputs black negatives have continuity to chassis ground? And, can I see if the subwoofer high inputs black negatives also have continuity to chassis ground? I know this equipment is not overly great or expensive and is just for a reasonable shop stereo. I just do not want to screw it up on installation. Blessings if anyone answers.
won't it have a negative side-effect on the poweramp now ? won't it influence the sound that is produced by the main speakers because the amp not only drives two front speakers but also the subwoofers amp ? (i have a denon av-receiver with pre outs to a denon poa-2600 power amp for the front speakers. i don't feel comfortable driving the sub-amp by this power amp so i use the sub-amp for filtering, with sub-amp connected to the sub-out of my av-receiver . The av-receiver drives no front speakers, but it powers the surrounds and center in case of watching a movie )
For the love of God, flip the blinds over! Hahaha when the sun peeks from behind a cloud, there’s no seeing what’s on the board.
Hi, I appreciate this information. I'm connecting my system today. I agree with your stance on using the high level inputs. I'll be connecting a vintage Harman Kardon 330C to a powered sub via the high level inputs on the sub. The 330C features 2 channels, "speakers 1" and "speakers 2." There's a separate pushbutton on/off switch for each. I already have "speakers 1" connected to a set of towers, so if I connect "speakers 2" to the high level inputs on the sub, I won't have any concerns or cautions like you were discussing with the grounding out of a bridged channel or anything, correct?
Thank you.
I have connected the second speaker out of my pre to the subwoofer 👍..
Hello Paul...hello youtubers...question? Does anyone know if the high level Neutrik speakon connection plug (sub end) are all the same ie are mj acoustics..rel..mk all the same type of plug.? I can purchase the high level lead from a company online and they sell the rel high level Neutrik speakon lead (3 wires) problem is I have a mj acoustics subwoofer and they are not sure if there cable will work with the mj acoustic subwoofer? The rel lead is considerably cheaper than the mj acoustics lead and as such would like to buy the rel one to allow that saving...how can I find out? Is the pole/pin configuration different between the 2 ie 2 pole,3 pole and 4 pole ect? Nobody seems to know the answer! Any help would be appreciated.
Give examples of subs with built in high level input. No rewiring required please.
I love my Velodyne.
@@mikecampbell5856 Mike can you help me out I am new to this when you using your amplifier high level on your subwoofer which one is basically the best volume to use the preamp on your receiver sub out to turn it up or just leave it down and turn the volume with the amplifier from your subwoofer high level to blend in speakers thank you
@@petercollie9251 Hi, when using the high level (speaker level) input and output terminals on your sub, set the crossover to about 100hz, play some tunes and turn up the sub volume level until it becomes noticeable then back it off a bit. When using the RCA sub out on your receiver, all you have to do is set it to a level that sounds good to you, the internal crossover on the receiver will take care of the levels for the most part. Use the line or LFE input. Some subs have a L and R input. Use the L. Check out the menu for your receiver if it is a surround receiver. You can set crossover frequencies and levels with your remote and customize your sound. You can have a blast doing this.
At 6:34 we paused and placed bets on how long it would take Paul to catch the goof. I was naive and lost the bet.
Yes,how about series to high level input?
what if you use a tube amp for amp out signal?
So I just learned that all subs are grounded so I can’t connect my amp on high level inputs without short it. So that didn’t answer my question at all because that don’t make sense.
What I really wanted to know is how connecting the sub on high level input affects the impedance on the amp because my speakers are 4ohms and I don’t want to go lower with the risk on breaking it.
I know this comment is a yr old lol, but both the high & low input’s are attenuated in the pre-amp stage in your amp & do not affect the output (power rated) section which includes the ohm rating. So it wouldn’t hurt it.
The power rated section (amp output) is what you match by the wiring configuration of your subs, which cant go below amp’s ohm rating or the amp will pass much more current through that path which lacks the rated resistance, likely frying the amps power output sections. The high level input would have nothing to do with that situation though, as all hi-in is doing is telling the amp to knock off some gain sensitivity so there’s no input clipping.
Is not that what REL subs do?
Hi Paul. Merry Christmas to you and your family. Your explanation really threw me on this one. I also use the high-level inputs on my sub from my Power Amplifier, but l then use the high-level output of the sub to my speakers. I would have thought that would be the correct way? Am I missing something? Keep up the great work. 👍
What if the sub has high level inputs AND outputs?
What do you do if your amp has a balanced output, but your sub doesn't have a balanced input?
You ground the sub in another way.
@@razisn how ?
@@toxotis70 See my reply to Sean Mangan below or visit the Rel site or look at the related Rel videos on youtube
If you go the first route, what’s a good level to set the high level at or do you just play it by ear so to speak?
Btw, is this the same as High Cut? My Yamaha YST has both High Cut and Volume controls...
Happy Christmas to all at PS Audio and thanks for your videos during these awful times! ✌️💕🇦🇺
Thanx for sharing. I,m trying to connect from an avr high level out (tapping center sp out) to a subwoofer low level in terminal. is it safe to do? I already run pout of subs out. Using 4 rels for LFE, but I like to create rel 3D by adding 3 more subs to 1:mains, 1 to Center, 1 to surround. I have extra subs I can use but they only have line in or LFE available no high level in. perhaps using a high level in line out converter solves this? Anybody?
I'm also in Edmonton nice
what if I have only one set of binding posts?
You can use the same binding posts for your main speakers and sub.
@@jasonrstang oh cool. I thought the amp would explode lol
Are REL subwoofers common ground input? Are B+W subwoofers common ground?
Thanks for all your educational videos!
If both of your amp terminals are hot, like in a balanced differential amp, you cannot connect to the ground terminal of a REL sub to the amp terminal. Instead you only connect the hot terminal of the sub to the positive terminal of the amp and you need to connect the ground terminal of the sub to a true ground on the amp. That could be the phono ground post or, better, the return of an unused RCA connection on the amp or any other connected component for that matter. The REL sub just needs to find a true ground reference. No idea about the B+Ws.
You can connect an active Rel sub with high level connection to virtually any amp but the method of grounding will vary depending on the amp. The issue arises because you are really connecting an amp to your amp output, not a passive speaker. Having a single pair or two pairs of speaker posts on the amp is irrelevant. These are usually connected in parallel and are there just for connection convenience, instead of trying to connect multiple wires to a single post.
@Lloyd Stout what are you talking about?
Im not an expert but If the problem is that you could short the negative amp to grund why do you even use it? You could youse the subwoofer it self as the black chanel
High-level inputs to a sub sounds wonderful on paper. But the theory only works if the sub amp has no sonic signature of its own - which every amp does. There are other reasons to avoid high-level input but this reason alone should squash the desire to do so. Besides that, the sub's signal is now passing thru 2 amps rather than 1 amp which at least theorically could induce time delays. And in the case of the REL subs, one is forced to use REL high-level cables which of course will also induce their own sonic signature and hence most likely with be different than the speaker cables' sonic signature. So it seems to me that those who boast about the supposedly superior sonic benefits of high-level inputs are relying more on what they read and imagine rather than what they actually hear. Because based on the above (and more) high-level inputs should actually cause greater differences, more distortions, and potentially more time delays than low-level inputs. What were they possibly thinking (or smoking) when conceiving the idea of high-level inputs?
Thank you for this. I have been saying this for a few years now as everyone beats the REL drums.
Well Paul McGowan advocates using high level inputs. Is he also relying on what he reads rather than what he actually hears? 😀
And, how can you relieve your mains with a high pass filter??? Does this mean that putting filters into the speaker signal is preferable to filtering the line level signal??
@@Hikebike365 Based on what I stated earlier, I suspect it means, what were they possibly thinking when deciding to go the high-level input route? The experts claim we would get the main amp's sonic signature carried by high-level inputs to the sub and indeed it may. But at what cost? Doesn't really matter because the sub amps have their own sonic signature so their theory is already blown to hell not to mention all the other sonic baggage high-level inputs bring to the table. An additional and very important point I neglected to mention earlier was, with every component the input signal is further degraded which implies the high-level input signal at the sub is now more compromised because it passed thru two amps insteand of 1 amp. Seriously, what in the world were they thinking? Fundamentally, it seems to me the easiest most efficient, and greatest sonic benefits implies staying with low-level inputs. It can work rather well. For example. th-cam.com/video/tNh-aFORuZ8/w-d-xo.html
@Lloyd Stout These kind of comments are rather humorous. Did it ever occur to you that "professionals" are often times just as lost as the rest of us?
Making the sub parallel to the main speaker means a relatively wide area where the sub and the main speaker overlap. That creates and interesting mushy phase mix of lowish frequencies that might completely overshadow the character of the single power amp that you want to preserve. Tell me why this is not a problem.
@Art DIY In the configuration that Paul suggests, the main speaker gets all frequencies, including frequencies close to its lower capability. That means that the main speaker will have considerable phase and magnitude characteristics there. Without a sub this is not a problem, as we are not _very_ sensitive for phase. But with a sub we add a driver in the same frequency area _with a different phase characteristic._ Depending on the main speaker enclosure and driver type, we get an interesting, frequency-dependent phase-and magnitude mix, which could lead to very loud or suppressed frequencies or less clarity (less tight). This all depends on the sub-position, of course. You cannot fix this with a simple phase-knob unless it knows the type of the main speaker. But maybe there is a trick I don't know that makes such a knob okay.
In short: it is very difficult to get a nice characteristic and adding a phase knob might also alter the character of the lot.
To avoid phase and magnitude problems, we should minimize the overlap in frequencies and make the switch at a frequency that both speakers can reproduce comfortable. But that means a crossover, which is not the configuration that this video is about. And naturally, this adds even more character to the signal than the main amp (I might hope).
Another discussion is whether a lot of "character" is added below 100Hz that cannot be reproduced with an equalizer. Does it matter? Or is it that second-order harmonic distortion that is so beautiful? But then we are talking about beautifying sound instead of reproducing it with high fidelity. This is a matter of taste.
In studio equipment, crossover is almost always done at low signal level or even in the digital domain. A power amplifier for each frequency range drives the speaker directly, so it has tight control over it. This gives you _accurate_ sound reproduction. A warm recording will sound warm, a sterile recording sterile and a bad recording, unfortunately the majority, horrible. You can literally hear the limiter "rattle" in a lot of modern "loud" recordings.
@Art DIY if the combination works: please enjoy it!
I'm merely saying that from a technical standpoint, the success of Paul's suggestion is very dependent on specific combinations of equipment. This is why I would personally not advise it as _a general solution._
When I could compare, the high level input does indeed sound better and I would use that if possible. If all I had was the low level I would use that without concern, the difference is not huge on any of the subs I have tried.
@Lloyd Stout A huge difference in favor of?
@Lloyd Stout Yes a huge difference in favor of which?
Good afternoon paul my name is David.
Y wish please if you that explanation to conect high level input to a subwoofer with the real sibs and speakers .
Y hope to see you in the next video
That sonic signature of the power amp will be completely swamped by the the sonic signature of your subwoofer driver
so you do not loose some sub channel information from 5.1 movies with 5.0 on av receiver and high channel input on sub from front speaker output?
As I understand, the movie .1 channel has +10 db and in a 5.0 config the av receiver would downmix this +10 db lfe signal so you would loose probably some movie bass
+ the .1 channel mixed from my amp into the front speakers would end in my sub + front speakers at the end, probably not a big issue...
so for 5.1 movies and a yamaha RX-v685 + Canton Ergo AS 650 SC Sub, is high level input still a good choice?
@Lloyd Stout oh lol thats not in my budget, I spend every month half of my 8h/week student job payment on tech from ebay...
but the yamaha v685 ypao setup might do a ok job and I will check what I like more, yes... atm my music on the Canton ergo 670 dc fronts with 1x180mm woofer could have more punch with my canton ergo as 650 sc subwoofer
I use the high level inputs on my two channel music systems and the low level input on my home theater. I never listen to music on my home theater system.
Problem is that most subwoofers have a crap circuit built into the high and low pass on speaker level inputs. Most subs just use one garbage electrolytic cap feeding the high pass. I have read from crossover gurus this creates response problems in the stereo speakers passive crossover.
@Lloyd Stout
Garbage advice.
There is a reason that the venerated REL now offers an LFE input option. Because it's better.
-✌🏼
A simple search for the top subwoofers of a given year affords a myriad of options for the buyer.
@Lloyd Stout
Crazy Paul included theater along with two channel in his stirring white board dissertation. As if they are intertwined. He's so far removed from the everyday user it's comical. And just for the record, my processor plays two channel with four subwoofers using LFE as good as any system I've ever heard.
Wait do i get that right now... u basically take just the sound signal, from, say ur main speaker channel, so u double plug the main channel and run one pair cables to the speaker and one pair cables to the high lvl input on the sub? Or did i Literally got it all wrong?😂
So Nice 💘💘💘💘💘💘
i have my amp to elac sub to high level ins. works well with blended crossovers. with low level rca in if u use intergrated amp. some cannot control volume of subwoofer. need preamp .either active with power amp. or passive with intergrated. or adjust vol. of sub. to blend with speakers. both can activate different sound signature.
Most AV systems have a setting for big speakers or small speakers where the bass frequencies are NOT sent to small speakers so that they can play louder without woofer cone breakup and the bass is sent to the subwoofer via the LFE output. in this case a high level input won't work. Also my sub has a low level input (from your preamp out) and out that would go to the power amp can be low frequency limited for the same reason as most AV systems.
Hi, PS Audio
Why some company set parameter in Voltage of limiter setting and some company in dB ? May be dB is better to understand than Voltage. Please explan
Most subwoofer amp boards usually don't have high-level input port...are we DIYers supposed to make such a port like by adding a large resistor?
This is just silly -- we're talking about a very low-pitched octave or so, an octave that has no audible "sonic signature" to speak of. Even if you don't believe that, do things Paul's "proper" way and whatever little "sonic siqnature" the power amp has down at the low end of the audio spectrum will be *added* to whatever "sonic signature" the sub's amp has -- IOW, Paul's recommendation presumes that the subwoofer has a perfectly transparent power amp, which is more than a little naive. The character or timbre of a bass note comes from the mid-bass range, not that lowest octave or so, thus it's your L+R speakers that deliver the difference between an acoustic bass note and an organ pedal bass note, not the subwoofer. IMO, you'll be doing yourself a favor by driving your active sub via the same preamp outputs that drive your power amp, using a couple of simple Y-adapters if necessary. My sub does have "proper" high-level inputs, BTW -- and as far as my ear can tell using them confers no audible advantage whatsoever.
Having the side speakers trying to do the bass that you bought a subwoofer to do better is not always a good idea if you want the highest quality deep bass.
One would think so, but one would be incorrect. Speakers, unless they are designed as limited range satellites, are designed to take the full signal. By adding the sub you are really augmenting the speakers for the low frequencies that they cannot produce adequately. For example, in case main speakers are 2 way, what you create by adding subs is a 2.5 way speaker.
@@razisn Of course stereo speakers are designed to take the full signal but it doesn’t mean they perform well in the deepest bass. Usually smaller speakers are using tricks to produce deeper bass that yield poor decay performance and a distortion that can become multiple percent at higher volumes. Your low distortion subwoofer might produce a very clean 50Hz that then combines with some smaller stereo speakers outputting 20% THD on top of it. A smaller woofer of your stereo speakers will hit the excursion limits much earlier creating compression distortion and some smaller speakers also make much port noise. A major benefit of high-pass filtering the side speakers is that your power amp can use the power focused on what the side speakers are better at. But of course adding high-pass filtering to your side speakers is best done on the line level or in a DSP before your audio hits the DACs and power amps. My favorite approach is using DSP where you can do much better optimization of frequency response and phase (e.g. using miniDSP).
I just found out that TH-cam unsubscribe me from this channel...... why TH-cam why!!
If your system is for Home Theater and balanced, the balanced connection to the subwoofer is better. I can see this being more applicable to an audio only system. Going from a single ended connection on a subwoofer to a balanced, there is a very noticeable difference. The subwoofer plays deeper and louder.
I must have missed a lot thru the years, hard to make sense outa that
Its not difficult. Let's break it down.
Question: Is the high impedance input simply directed through a high value resistor?
Answer: It IS a simple resistive divider in many subwoofers; but, that creates a problem for balanced amplifier outputs since the inverted output would be shorted to ground in the subwoofer.
Addendum: The solution to that, for subwoofer designers, is to take both inputs through the resistive dividers into a differential amplifier. Then both sides of the connections would go through high impedance resistors, thus allowing it to work for both balanced and unbalanced amplifier outputs.
@@timharig ok, so this video is for a designer of the circuit to allow that the sub to utilize the speakers output?
I didn't understand when he said that the sub wouldn't draw watts from the power amp just the signal? lol.. this reminds me of algebra...
@@yrulooknatme Well no. You do need to know this when attaching your subwoofer this way. If you have a balanced amplifier output you could short and damage your system if the subwoofer isn't designed to handle the balanced inputs. Then he describes how the designer should handle that balanced inputs which you do not need to fully understand as a user.
You are going to a have a very difficult time in this hobby if you do not understand some basic mathematics and some basic electrical rules. Understanding this video requires understanding voltage and current dividers.
When impedances are wired in series, the current going through them is is the same; but, the voltage is divided across each impedance in proportion to its impedance the total impedance.
When impedances are wired in parallel the voltage across them is the same but the current is divided between them inversely proportional to each's impedance compared to the total impedance.
In this connect, the subwoofer is in wired in parallel with the speaker. So the voltages across them are the same but the current is divided between them. Because the speaker's impedance is only a few ohms compared to the subwoofer's impedance which is on the order of kilo-ohms, very little of current is siphoned off of the speaker's line. If the speaker impedance is 8ohm and the subwoofer impedance is 100k ohm, then the subwoofer is only drawing about 0.0008% of the speaker's current.
Then in the subwoofer, that small amount of current travels through two resistors in series to divide the voltage to a level appropriate for the subwoofers amplifier to handle.
@@timharig thanks I'll keep reading this till it starts to sink in a little... I never got into active subwoofers and surround sound systems. always had stereo with woofer and tweeter and sometime mids. To me this sounds like a better way to utilize a sub. if you had one. I've always wondered what a bridged amp was and now I know. sure don't want to run that to ground.
thank you
Sounds like gibberish. A PS Audio customer for many years: Want to connect two REL subwoofers to two balanced amplifiers. This video does not help at all. Am I supposed to go out and buy 100K resistors?? This video just create confusion. Is there a concrete and simple way how to connect the subwoofers?
How i ask my doubt ??
High level inputs should be differential indeed as Paul explaines. Works universally. Crap circuits like REL's where you have to connect somewhere to the chassis although nothing is provided for that is a solution not matching all real world situations. And it is costing pennies at most indeed as Paul says to implement it well. Suggests REL lacks the proper engineering skills or mayby just buys cheaply from China. (I have a REL and found difficulty connecting it with my Pioneer Kuro: RCA had a hum due to a grounding loop, high level speaker output balanced)
Sorry, but that comment is just a big steaming load of "REL bashing" horse sh!t...
At best it sounds like you bought a product you clearly have no idea how to PROPERLY use-for Christ sakes, you hooked your sub up directly to your "plasma TV" which is about the SHITTIEST hit/miss connection scenario imaginable for performance since the audio output stages in all those Plasma TV's were utter "lowest common denominator" garbage to begin with (talk about using cheesy "Crap Circuits"!) and you're wondering why you are having "difficulty" with performance and grounding issues with your sub?🙄
Seriously?
That’s called “User Error” dude, BUY A "REAL" STEREO/AV RECIEVER OF DECENT QUALITY AND YOU WON'T HAVE NOISE AND GROUNDING ISSUES ANYMORE!
What you're doing right now is the equivalent of someone buying a high performance sportscar then putting shitty cheap ass tires and brakes on it, using the lowest grade fuel and oil they can possibly buy and then getting online afterwards to ignorantly complain about the performance of their car like it's supposed to somehow miraculously turn shit into sugar...
I have used REL subs in multiple systems for over 20 years "without" issues (I just recently upgraded to S812's in one of my systems after listening to numerous competitor subs just to see if there were any other potential contenders to the throne so to speak) and have yet to hear any sub outperform the REL’s in a real world situation "when" connected and dialed in correctly.
BTW: You ARE aware that Paul himself uses REL's in his own home system and recommends them, right?
CLOSE THE BLINDS!!!
TL:DR
ALWAYS SET YOUR SPEAKERS AS SMALL IN BASS MANAGEMENT AND USE THE LFE INPUT OF YOUR SUBWOOFER AND MAX ITS CROSSOVER IN ORDER TO USE THE ACTIVE CROSSOVER OF YOUR PROCESSOR AND GET THE MOST ACCURATE BASS REPRODUCTION IN CONJUNCTION WITH YOUR MIDS AND HIGHS.
or take the word of a guy who cannot recall a name from two minutes ago who is stuck in the dark ages of modern audio tech.
😊
Thank you, mr. troll, for screeching at the top of your verbal lungs at us the exactly *incorrect* way of doing things, while rudely getting in another jibe at our gracious host.
Well done.
@@HareDeLune
LFE is the best way to add a subwoofer to a system.
PERIOD
@@Finn-McCool
Yeah.
So says the yowling troll! 😂
2:32 I like that😍💋 💝💖❤️
That’s dumb just come out of your pre amp to the subs, come out from balance output too lfe or if your subs have a balance input 🥴this is so stupid to do and old fashioned the way Paul is saying
Ive tried both HL and LFE for me HL sounds tighter
Don’t knock it until you try it. Huge difference in bass quality in my system. Huge!