Why does your head unit clip at max volume when your amplifier gain is all the way down? Is this normal? Does this mean I can never turn my unit to max volume safely? I thought I could turn my head unit to max volume and then increase my gain till I get clipping, that way even in the moments when I want to turn my radio all the way up to its loudest, I won't get any clipping. Idk man thought I had it figured out for a minute there but maybe not. (No audio shops around rural Arkansas but I'm learning)
@@RandoManFPV That's right. Pretty much everything clips when you turn the knob all the way to the right. Why? Because you're popping out more voltage than the unit is capable of producing without distortion.
Hey I’m setting the gains on a Zapco Studio 204 4-channel amplifier. My head unit is a Kenwood KEC-X704 which I’ve three preamps rated at 5.0V each for Front, Rear and Subwoofer. I’m trying to find the clipping point of the head unit using my o-scope before moving onto setting gain for the front channel. When I reach Volume level 29, the Vpp goes to 10.2V which is in line with the spec of 5.0V preamp. The thing is, it stays there from Volume level 29 to the highest of 35. When I take it down to volume 28, the Vpp drops to 9.0. The 1Khz waveform never goes into clipping though. Should I base my gain settings from Volume level 29 or does it not matter if I use 29-35 being that the signal does get driven into clipping at all? Or is there something about my scope settings that isn’t allowing me to see the clipping or is there an attenuation circuit that prevents it from clipping?
OK, I am assuming I am missing something obvious, but this doesn't make sense. Was the gain all the way down on the amp to start? I mean, you sourced the signal from the same spot on the amp for both Amp and Head Unit setting, but something seems off. When you put the probes on and turned the head unit up to get the clip, where was the gain of the amp? If all the way down, then i am thoroughly confused. The reason is that when you moved on to set the clip of the amp, when you first put your probes on, there was little to no wave. Did you change the head unit volume down all the way? Was it left at 62? Seems like you did something in between testing HU and Amp for clipping that would help tie this all together.
I'm very new to car audio, sans 35 years ago when I was a teen. I do have to say you make things easy to understand for old guys like me. I appreciate the effort you put into the videos as well as keeping all the fluff out. Well done my friend!
Maybe you have covered this in some updated videos, but youtube suggested me this one so I think I may chime in here with some advice. - The aux port is the worst source for calibration since there's an additional preamp/ADC stage that you may be clipping, thinking you're clipping the output stage of the unit. Also another phone will have a different max volume. - It's unlikely that any other input, bluetooth/usb/CD/Radio will have the same peak levels as a given phone, once in the digital realm inside the unit. - Setting a -5dbfs test tone close to the clipping point guarantees that up to 5dB of usable (and used by artists) headroom will be clipped. Use 0dBFs Here's to me, the proper way to do things, and how we generally do it in studios and live venues as sound engineers, but adapted to car audio environment: - Use your ears to check for distorsion, as it starts bellow the apparent clipping level on a low res oscilloscope. The sine will at some point have a buzzy higher pitched sound, you want to stay bellow that level. To check this, set the gain of the speaker amp preamp very low, this ensures that you're very far from clipping the amp input stage and the speakers, then proceed with the next steps. - Use a pure 0dBfs sine wave file via USB, CD/Bluetooth as it's directly digitally decoded and put the output volume of the unit to max. This ensures 0dBfs on the wave file will be 0dBfs on the DAC of the unit. If the manufacturer didn't brainfart the output stage, the signal should be free of distorsion. If it's distorting, lower the volume of the unit until it doesn't distort anymore and never go above that number in day to day use. - Now you have the absolute maximum undistorted signal coming out of the unit. - To set the gain on the speaker amp preamp, i'd then use the oscilloscope and refine with your ear. Your speakers may make have some distorsion at some frequencies that you may want to avoid by lowering the overall gain. - Now there's absolutely no way in hell that the sound will distort unless the source file is already distorted.
Good stuff ... thanks! I'm gonna break out my Tektronix scope today as I'm setting up a 5 channel amp. The level will be set to the RMS handing power of my speakers.
Tektronix scope you say??? You could hang a wet towel off the hardon I have right now for a Tektronics scope. You need it calibrated or just plain serviced you send it to me I'll use the chit outta it I mean return it within a week after servicing and calibration
I'm talking 14in Pringles can I could flex and lift do reps with a saturated towel with this hardon over a tektronix scope my friend. Whaaat that's awesome keep on keeping on while I go Meter out this fuel injection system to at least calm this curved and bent monstrosity of a pringles can. Plain massive and ugly but it throbs 4inches up in down in idle. Needless to say only the super whores have been having fun and I on every antibiotic known to man
quick question, i have a oscope and i setup my jbl a5055 which is rated @500rms at 2ohms on the monoblock side. I used a 40hz test tone at 0db and recorded a clean wave no clipping @ 37volts, doing the math that equates to 684rms could that be possible? i verified it with a multimeter (very good quality) my oscope is FNIRSI DSO-TC3 which again is decent enough?? i have two jbl a5055's bridged on the 4channel side (140watts rms x 2 bridged) , both of the amps recorded an identical 37volts with clean wave 40hz 0db test tone, clipping occured around 37.5 - 38volts
I just subscribed to your channel. You're right on the money with this stuff. I did a Google search for osciliscope fine tuning diy class ab amplifier. I saw how to set your gains and didn't know it wasn't a video of the internal components lol. I got stuck though because of how informative you are. Full of facts and math I love it. Also ima big car audio guy as well as my beloved home equipment. Anyways glad I found this channel. Can't wait until I finally buy a scope and can check certain capacitors to really fine to and build some SERIOUS QUALITY HI FIDELITY SHIT MAN!!! ILL BE ABLE TO.CHECK.STABILITY OF THE TRANSISTORS IM USING. SOOOOO MUCH FUN MAN LOL. I learned so much in the 30 to 45 mins I was straight glued onto your videos for the first time. Most of the formulas and convertions I already knew but I learned so much bout setting up errythang wit a MM. You really taught me some shit quickly my dooooooddd. Thanks man
I also want to build my own resistors because with all the amp equations you always have to select the nearest real value. Now of I could make my own half watt to 5watt resistors at something crazy like 56.8873 ohms I'd shit a brick n die of a heart attack mediately because I did something amazing there n all the big audio manufacturers straight Hite through the heart wit their invisible death lasers whenever the sensors on the Lazer cannons sense a higher fidelity product with THD .00000000000112% at full bore no clipping except I I wanted to "overdrive" a 4558 or something lol. Sorry for the rambling I eat sleep n breath this shit
The output transistors were BJT'S D718 and B688. With plenty I mean friggin plenty of small signal bjt and.bjt's all the way up from mw output to 20watts. So I went HAAAAAAAAMMMM AS FUCK on disassembly so hamam in fact I caught a hardon
Took a complimentary pair 718 n 688 and ran 100k5watt resistor between 718 base n 688 emitter with an inductor In-between. Coil was like 20wraps.ran 718 collector to 688 base n 718 emitter to 688 collector. Negative 12v supply and negative on a cut into aux cable( - input) to 718 collectoe to 688 base jumper. and negative speaker output came off of 688 emitter terminal and BOOM DID THAT PACK A PUNCH BABY. IF I WERE TO PUT IT IN AN ENCLOSURE AFTER FINE TUNNING WITH SCOPE PPL BE LINED UP SUCKING DICK FOR MY SINGLED ENDED 2TRANSISTOR SUB OR WHATEBER DA FUXK YOU WANT AMPLIFIER
Thank you for the video, it is very helpful. I was wondering when I'm setting up my gains on a subwoofer I only have access to disconnect my rear speakers for testing. Will this process work if I set the fade to the rear while setting the gains on my monoblock amp with the oscilloscope?
I would test all channels. Set the gain from the channel that is clipping lowest. So for the front or rear use the channel that clips first, left or right. That way when you turn your volume up neither channel clips. If you were to use the higher clipping channel it would be clean but your other channel might be clipping. I hope it makes sense.
I usually set my gains with a 0dB sine tone as I listen to a lot of non-mainstream trap/EDM. Is there something I can use to figure out what the maximum dB is of songs that I listen to, or can you recommend a dB sine tone I should use for my requirements? I know -5dB is the default but I'm not sure if this might be too much or too little and I'm really looking to maximize my gains. Thanks so much for any help you can give!
You might be able to play the song using audacity and getting the levels that way. But I think you've made the right decision to go with the zero DB tone. Especially if you got bass boosted music. One thing you can do is try a -3 DB tone and see how that works.
Hello! I have a weird issues of my sound, whatever comes to your mind, I've already checked it. I have Shit bass from subs. I tested all Components of Audio, wires, rca's, subs, amps, Head units itp.. My issues: - Different bass quality (in feeling presure too) - Different Output voltage from head units (Kenwood 7200dab new, Alpine cde 178bt) - Voltage on amps body hecked with: (Multimeter one wire to ground terminal amp, next wire to body amp (screw) i can have voltage on all amps dependent of instaled amp location. Now i have to 2volt on my sub amp, before 13v it always drops while reading voltage. - After changing the port of subwoofer to 25hz, i hear a sound degradation from vocal (music), sometimes moving the windows can improve the bass but very rarely. My score is on car closed, 151 db 37hz from 15,5volt to 12,3v voltage drop. but i dont hear and fell this power :/ I fight with this issue about 5 years in two mazda cars... If bass is ok, bass can lost after next enigne start. I recently sold my equipment Clarion sw 3012 and Crunch mxb 480, about 120 watts rms from this sub, and it played well in Renault Clio 3. And there was no problem with the sound at all... This voltage on amps body can degrade sound quality, mallufuncioning Head units? i added ground to amps body, i have 0,000v but problem of sound is still Can you help me? Mazda 6 2007r
@@ericdayman3568 Yes, everything is better. Yesterday i finished correcting instalation, distribution block, head units, amps from dist point. All grounds point fresh cleaned. Effect? not changed, subs blowing, sound bad... Its like Noise, Gain loop. Or EMI interfence.
@basserex4991 are you using the factory wiring from amp to speaker? I remember my buddies 2008 Mazda 3 had a similar issues. Everything sounded like shit, super distorted and gainy.
I am using DMM method from years never had problems but today when I changed sub I wanted 40VAC voltage but my DMM is not heading ahead 33VAC don't know my DMM went bad or my head unit isn't sending enough signal even though it has 5V pre outs. But what I noticed is my DMM tiny wires went super hot after trial and error so I guess my DMM isn't accurate anymore! Please guide me on the same
I have a question. Plus, I love your videos. They not like most. You give real numbers and proper facts, that is fantastic, and what I need, the right information. I am still learning all this car audio stuff. I have a 2ohm 800 watt car subwoofer setup, running a 1500.1 D amplifier. However, my amplifier max voltage is 6 volts and I need 6.7 volts to make 800 watts (goes over a bit). According to my equation. Can I set my LOC2 at 6.7 volts and be fine or have to stay at 6 volts and calculate that extra .7 volts to my 40 volt (makes 800 watts) setting on the amplifiers gain?
@@Navylus If I was to guess (which I totally am), I'd probably do 2kHz for mids and 12kHz for highs? Or maybe look at the speaker specs and just go halfway to what their frequencies response is.
First...thanks for this! I just installed a 4-channel amp in my truck and need to set the gains. Question...when setting up the HU, do you recommend setting the equalizer to a flat signal or to the settings that you would most likely have it at when playing music?
Hello, I have a question. On minute 2:57, I see where the wave clips (flat spot at top). I have the Abestop 2 in 1 oscilliscope, but I can't seem to get the ceiling to lower to where yours is showing. The waves go all the way to the top of the screen. I tried changing the range, but it still doesn't lower. I understand the time adjustment to space out the wave, but not lower the ceiling. Of course the instructions doesn't provide any info on that. Thank you.
I’ve got a 21 f150 with the B&O system. I’m adding a aftermarket sub. I bought the O-scope from your video. Do you have a video of finding the clipping point of the amplified head unit? I can find a ton of videos on testing a non amplified head units.
Hi I have installed in my car a 4-CH amplifier that drives a pair of 2 way speakers (woofers and tweeters) and an other 2-CH amplifier that drives a woofer. So to tune correctly the gains with the O-Scope I should run the below test tones: 1) 50 HZ, - 5 db test tone for bass on 2CH Amp 2) 1000 HZ, - 5 db test tone for mids on 4CH Amp 3) ???? Hz, - 5db test tone for highs on 4CH Amp What test tone should I run for the tweeters (highs)? I did one try with O-Scope and tuned gains at the maximum allowed values of the 4-CH Amp according to the 1000 Hz test tone as you mentioned but I noticed that I have disortion in higher frequencies (8000 Hz and above). What should I do for the hights? Thanks in advance!
I kinda understand but I don't understand. On my amp, there are 4 different twist style knobs and they all have different things and idk what to set each one for. I see the gain but what about the others? What should they be set to?
You might not need to use them, it will depend on the rest of your setup. If your head unit has a crossover then you just need to set the amp crossover to it's highest frequency so that it will have no effect.
Nice video just got the LM2020, I seen other video with DMM and the head unit should be flat , zero settings on treble bass and Mids, my concern is do I leave those setting there? If I want more treble will that change the clipping point from my head unit ? 26 on my volume is the point of no clipping 27 will clip
When setting EQ the rule is to always cut instead of boost. Only boost as a last resort. So if you need more trouble you cut the bass. Now if you use a zero DB test tone you've got plenty of room to boost the treble before it clips.
What are your settings on oscilloscope? Im using a different brand. How do i show clipping.i have a 4volt output on my HU and my oscilloscope goes from 2.5 to 5V theres no in between for 4.
How’s it going brother! Been learning so much from you and your vids, thank you for your time and effort! Got a request: I’m someone who has a factory head unit, an Audiocontrol Lc2i, an Audiocontrol bass restorer, and an aftermarket amplifier. I’m sure I’m not the only one with the extra bells and whistles :) Can you please teach us where to start checking for clipping, and where to go after each step until we’re done tuning for clipping? Thanks again brother!!
ok you set the gains on the Amp, but what about the speakers? Are they not taken into consideration at all? What if the speakers I'm using can handle less than what the oscilloscope showed for the amp?
Loving your bodies after a long break from car audio. If you use a 1k test tone for muds and highs and say have you crossover set at 80-100h will the lower h distort/clip first?
@@DIYAudioGuy Maybe an oscilloscope test and video is in order? Every video I’ve watched says use a 1k test tone. Maybe there’s a better frequency to ensure you get the best out of your amplifier for sound quality? Maybe 1k needs myth busting? Could be a job for you, I’ve found your videos really educational and I really enjoy watching them. Keep up the great work. 👍🏻
Hello can you please tell me how you checked your phone for clipping? I just ordered the same oscilloscope of your link. I will be connecting to the head unit via Bluetooth with my phone.
I just turned the volume on the phone up all of the way, connected the BT to a device, turned that device up about half way, and played a test tone. I tried it on several different devices, I also checked the headphone out.
Good video. Can u answer one thing for me. How is this accurate without a load on the amp? The rail voltage will change with a load applied. Could you do this with resistors or a speaker hooked up to see if it’s the same?? Love the channel.
@@gregblau8082 Makes sense. I actually just got this same dmm. Tried with and without speakers on a head unit and it was the same. Have not tried on A sub amp yet. Would be fun to test how far off it gets the more power you got.
Question: I have a powered(amp built in) JL sub. This method or the oscilloscope wouldn’t work unless I removed the speaker and measured at the wires inside the box, right? This video will help with adjusting gains on my separate 4 channel amp though!
I have the Alpine SA55V. A 5 channel amp. Where I can bridge the four channels down to 2 channels while still having channel 5 for the sub. The question is would I still use the 1000h tone for the bridge mode since I’m using them for higher power components?
Question. It looks like you found where the head unit clipped by probing the amp at the speaker outs. Am I crazy to think that it should've been tested on the RCAs? Wouldn't probing the speaker outs be show results for the amp? If that's not the case, then was the gain set all the way down when testing the head unit for clipping?
It's a good tool, but to expensive for a hobbyist or DIY'er that may only use it once or twice a year. If I were a professional working out of a shop I would get one.
Hi, I think i'm misunderstanding a step in this "process" because something isn't making sense to me. You set the headunit so that the peak is just starting to flatten out, but then I don't understand what "volume" you set the headunit to when you start adjusting the gain. Because wouldn't where the gain starts clipping change depending on where you have the volume of the headunit? And, if you start adjusting the gain when the headunit is almost already clipping, wouldn't the headunit start clipping immediately after you start adjusting the gain?
You can do that through the amplifier or head unit. Sit everything to a moderate volume level and ensure that nothing is clipping. Then crank the phone all the way up and see if the wave form shows clipping.
I tried this method tonight in hopes of being able to Bluetooth the sine wave into the system via TH-cam. My sine wave appears to be made of a wave itself. Any clues? Not sure what’s going on.
I see different methods of setting gains and head unit volume. Most people say to turn off your eq settings, bass boost, loudness, etc on both the head unit and amp before setting gains. Others say you need to set all that first so you can set the gains and your amp/head unit won't clip this way unlike if you set the gains with everything off and then added them afterwards. So which is correct?
Those that say to set EQ before setting gain are wrong because they are setting their EQ incorrectly. When setting an EQ you cut the loud parts and only boost if it is a last resort. Their advice is based on a "two wrongs make a right" world view. The bass knob/level is a little different. Most of these need to be up all the way. Same bass knobs are actually bass boost controllers -- I think Pioneer does it this way. In that case you want it set to flat.
Why did you use a -5db track? I thought were suppose to use the 0db track. I have kicker marine speakers and just ordered that scope tool since I couldn’t get the voltage anywhere near what JL audio said it should be for their amp by using a multimeter. Hopefully this Meath is works!
Use a zero db tone for everything but the amp. For the amp set it to taste. Most music is -5 db and I have found that -5db is good for mids and highs and -7 to -10 is good for subs.
Great video but with all this information im still a little confused with one thing. I set it so my amp wont clip but now confused since one set of speakers rms is 60watts and the other set is 90watts rms coaxial speakers. Is adjust the rms somehwere else? I have kicker cxa360.4. And speakers are jbl gto 939 and 629. Any help is greatly appreciated
The amp rating is based on the amount of power the amp can produce. The speaker rating is based on the amount of power the speakers can handle. So set your gains using the lower of the two numbers.
Hi was wondering can you tell me if this is correct?I have head unit connected to Amp.With gains on amp turned all the way down,Connect o scope to one of the front speaker connections.Then turn head unit volume up untill the o scope shows clipping.Here is were i am not sure.Once i find the clipping volume on HU and turn it down till its not clipping do i leave the volume at the level and then starting turning up my gains?Or do i turn volume back down on HU and start turning up gains?Thanks
I have the same question. Did you ever figure it out? Wasn't sure if he turns the head unit all the way down or leaves it at volume when setting gain on amps .
After watching your videos, I bought a small oscilloscope and set my gains. I found my head unit would not clip even with volume maxed out (50). I set my gains with the head unit all the way up. I set both a 4 channel and mono amp for my subs. It didn’t n take much gain to start clipping, probably about 1/4 turn. Does this mean I am not getting the full power available from the amp?
@@DIYAudioGuy that great news. I am just starting to understand how all this works, your videos are very helpful. Thanks for getting back to me so quickly on one of your older post. You have a new subscriber.
If I am checking the clipping point of a factory head unit with a factory amp, do I check it at the speaker before or after the amp? 2011 f150 raptor with Sony system for example
Both, the seagull going into the amp needs to be clean as does the signal coming out. Just be aware that the signal going into the factory amp might be a data feed, so you might not be able to read any kind of signal off of it. It's not unusual for newer cars and high-end cars like your raptor to have that "feature".
I have installed a 4 channel amp but i am going to have a 2 ohm impedance for my mids. Would i still be able to set the gain without my speakers connected?
I assume you set the volts to DC on the oscilloscope when setting amp gains? Another channel had said to set it to AC volts. Which didn't make sense as the car's electronics run on DC.
How do you disconnect the (non-sub) speakers from the headunit to set gain on the headunit in cases where the wiring harness to the HU includes power and speakers?
Just wherever it is the easiest to get to. Since it does not sound like you can easily connect the probes at the harness behind the dash it might be easiest to do it at the speakers.
I have 600W RMS @ 2 ohm mono amp! However my subwoofer is rated at 400W @ 4 ohms, wouldn’t my amplifier clip over 34.64 volts (√600W*2Ω= 34.64V)? If so, with the subwoofer above my amplifier will output at 4 ohms √400W*4Ω= 40v. That seems a bit high. I was thinking because my mono amplifier is a 2 ohm stable class d amplifier, shouldn’t the formula technically be √400W*2Ω= 28.28V and that shouldn’t be clipping cause 35V+ should clip cause that’s max voltage output out of the amps channels? Or am I just overthinking 😅
Most music is recorded at -5 DB, so that is probably the best test tone to use. If you use a 0DB tone you leave power on the table. If you want to push your amps and you are not afraid of the occasional clipping then go with -10 DB. Does not matter if you are working the head unit or the amp.
Connect the phone to the head unit, turn the phone all the way up, set the head unit to about half way up, and then measure the output of the head unit for clipping.
If I recall correctly CDs are recorded at -5 dBs, and that is the standard. So for that reason a -5 dB test track is probably the best one to go with. But people use different test tracks for different reasons and it's probably not that big a deal.
@@DIYAudioGuy See - this is where it gets confusing.....SO if I am supposed to use the SAME speaker outputs that are on the amp....is it safe to assume that all the gain settings on the amp need to be at their lowest position? Then - turn up volume on HU to see where clipping occurs, then back off a little to no clipping on sine wave. Then - play test tune at THAT volume on the HU AND slowly turn up the till clipping occurs, then back off a little. DONE. is that the right sequence of events?
@diyaudioguy The math makes sense for 4ohms but at 1 ohm its different. My amp will do 44.7v cleanly which would work perfectly to my amps spec of 500 watts at 4ohms! When done with 1 ohms my target voltage would be 34.7 which would equal 1200 watts which is my amps rated power at 1 ohm but if I tune using a oscope my amp clearly puts out 44.7 watts cleanly so tuning with a oscope means im getting too many watts at 1ohm? Just curious why the math seems odd here and almost like I shouldnt use the max clean output when doing 1 ohm thanks for any advice!
This Does work until you get a big amplifier the waves are too big and the current is too powerful for you to be able to see the sine wave on a toy oscilloscope. I was setting my JP 234 which the oscilloscope did give me a little bit of an idea of how clean the signal is coming out of the jp. It's a little dirty. Okay so I can't see the top of the sine wave you can motivate one side all the way down so you can see just the top or just the bottom from the middle and it's so much power I can't see it
Hi I have 4 midrange speakers on a 500.4 Amp. Where in the Amp can I adjust to make my speakers alittle louder . On my headunit when I turn volume up to 25 it is not loud enough
Why is it that when figuring out where the head unit clips you had a sound wave but when you went to set the amp gain that sine wave was gone and in order to get it back you had to turn the gain up. Am I missing something? The oscilloscope was on the same two terminals for both the head unit test and amplifier test, so why did the sine wave go away when beginning to set the amp gain. The head unit was still turned up.
Continuity error. You're the only person that's caught that. This video required multiple takes. At some point in between takes I had turned to the gain all the way down.
Where was the gain setting when testing the head unit sound wave. I understand when checking the amplifier sine wave you started with the gain at its lowest setting but what was the gain setting on when first checking the head unit? Wouldn’t it need to be turned up a bit in order to even see the sound wave? Am I over thinking this? Thank u for the reply
Can you do a video on how to calculate a port, tune etc using pen and paper or along with a free sub box calculator? Anything but winisd. Winisd is confusing.🤦🏿♂️🤦🏿♂️🤦🏿♂️ Preferably pen, paper and a calculator. I love all your videos. I’m learning.👌🏿👌🏿👌🏿🔥🔥🔥
Probably because your amp can't produce the higher voltage at the negative 5 and negative 10 DB settings. Make sure you have everything wired up correctly. That's the kind of thing that happens when you try to run a 2 ohm stable amplifier at one ohm.
I've read two ways of doing this. I know some use 0db or say -5dB test tones. And it was said in different places if you use a -5dB, you use that to check when the head unit distorts. Then you use the -5dB to also set the amp gain level. Then someone said if you do that, then that is like having a -10dB setting on the system. And so they said you should always set your headunit volume via 0dB, and then you can use whatever to set your amp gain levels to, i.e. 0dB, -2.5dB, -5dB, etc. I'm wondering, which way is the correct way? I'm going to guess it makes sense to just set the head unit volume via a 0dB level tone, and then pick whatever for the amp gain level. I plan on doing that using 0dB on my head unit and set it, and then putting a piece of tape on my amp and marking amp gain knob at 0dB, -2.5dB, and -5dB test tone, and then playing with the knob to figure out where I want it via listening to music I'll probably start on 0dB on my amp knob, and listen to something soft like Tom Petty, and if I don't have to max the volume out on the head unit, then I'll probably leave it. But if I do, then I'll turn the amp gain knob to my -2.5dB mark and see how that goes.
@Natural Creature I ended up buying a DD-1, which I later sold. But I used that to set my gains, I did tests on 0db and -5db. I found 0db was at the first mark on the amp, and -5db was at the 2nd mark. I did tests and found I could leave it at 0db since I never maxed the volume on my head unit when listening to my test music on the 0db mark. Also, when I used the DD-1, I had my Alpine head unit volume set to max. Using the DD-1 was so easy. I do recommend buying one used, use it and get a ultra fine silver marking pen to mark dots of 0db and -5db on your amp for future reference and then sell the DD-1 when done.
You may be the first who can *actually* do a how-to for WinISD and have it understandable. I have watched so many videos on WinISD and it is still confusing. When the T/S parameters are entered does WinISD spit out "a" box specific to the numbers or is WinISD used to manipulate the T/S numbers to get several different custom boxes???? No need to answer - it is just one of the MANY WinISD questions
Because that same speaker is going to have to reproduce frequencies higher than 1000 HZ. So you're trying to find something that's a reasonable compromise between all the potential frequencies it might play.
When measuring voltage the meter does not put a load on the amp. There should be very little resistance. I'm not a multimeter expert, so I'm not sure how they go together and what kind of resistance they have. In voltage mode the meter just measures voltage. Voltage isn't power, there's no work being done. If you run a given voltage through a 4 ohm load then you get watts, that's power. So if it were hooked up to a 4 ohm load you use the formula to calculate the power in watts. Hope that makes sense.
Let’s do a hypothetical. Say you are setting up a gain knob on 4 channel amp and the only tool you happen to have is a multimeter. You would obviously use a 1000 Hz test tone at around -5 dB. But just out of curiosity you play a 50 Hz test tone at -5 dB. Would you get the same voltage reading? From what I understand and have experienced you shouldn’t right? Which leads to my next question. The operating range for a multimeter is around 50-60 Hz because our power outlets in the US are around 50-60 Hz. Wouldn’t that make a 1000 Hz test tone inaccurate? Please correct me if I’m wrong I want to learn things.
@@TheDeluxe4O I think however, that what I Said is only valid when the speakers aren't connected. Because if they are connected, the impedance depends on the frequency, which will in turn change the output power of the amp.
@@devnull182 so I just tested this and it seems that the voltages are different when I use the 50Hz test tone and the 1000 Hz test tone. Any idea what going on? I made sure I didn’t have any filters on the amp.
Can anybody help me build a Balanced line driver for some Old School Soundstream amps and crossover? I have amp schematics and Pin out for the line driver, but all of the schematics I see are from home audio. I'm stuck and don't know where to look. If I'm in the wrong place and being rude, all apologies.
If you did that each individual frequency would show up as a different waveform on the oscilloscope and all you would see is fuzz. Pink or white noise is best used with an RTA so that you can visualize the frequency response.
Just to be clear for any newbies, all pink noise is not the same. It's unfortunately gotten rather generic in meaning. A true calibrated pink, starts in the infrasonic, and goes slightly into ultrasonic. ie, beyond human hearing. I've seen (on the scope) some slump shouldered pinks that don't get going til 120ish HZ, and have very little energy after 15k. A good one, should almost look like a block of signal equal db at every freq. And definitely don't download your pink from YT and it's compressed hell of audio.
@DIY Audio Guy yes, I even tried the volume know up more. And these are one of the olders that are still clean. But 1k test for the jp 84, whole sine wave is squiggly. Prior to that the deck was clean @26/35. It plays fine. But the signal is just dirty on my amp. I'll double check it in a bit
According to TH-camr DAmoreEngineering the correct formula for calculating the "Real Power" of an AC circuit with a reactive (non-resistive) load is: V(rms) x I(rms) x cos(Φ) (where Φ is the "phase angle" or the phase difference between the voltage and the current) See his video here: th-cam.com/video/qwxlnSDv9wY/w-d-xo.html Any thoughts?
I disagree with your flagrant use of capital letters but I agree with your comment. Clipping point will change when the speakers are connected. I've tried this.
You can get the Oscilloscope here*: amzn.to/3tulKGD
*affiliate link
Why does your head unit clip at max volume when your amplifier gain is all the way down?
Is this normal?
Does this mean I can never turn my unit to max volume safely?
I thought I could turn my head unit to max volume and then increase my gain till I get clipping, that way even in the moments when I want to turn my radio all the way up to its loudest, I won't get any clipping.
Idk man thought I had it figured out for a minute there but maybe not.
(No audio shops around rural Arkansas but I'm learning)
@@RandoManFPV That's right. Pretty much everything clips when you turn the knob all the way to the right. Why? Because you're popping out more voltage than the unit is capable of producing without distortion.
Hey I’m setting the gains on a Zapco Studio 204 4-channel amplifier. My head unit is a Kenwood KEC-X704 which I’ve three preamps rated at 5.0V each for Front, Rear and Subwoofer.
I’m trying to find the clipping point of the head unit using my o-scope before moving onto setting gain for the front channel. When I reach Volume level 29, the Vpp goes to 10.2V which is in line with the spec of 5.0V preamp. The thing is, it stays there from Volume level 29 to the highest of 35. When I take it down to volume 28, the Vpp drops to 9.0. The 1Khz waveform never goes into clipping though.
Should I base my gain settings from Volume level 29 or does it not matter if I use 29-35 being that the signal does get driven into clipping at all? Or is there something about my scope settings that isn’t allowing me to see the clipping or is there an attenuation circuit that prevents it from clipping?
OK, I am assuming I am missing something obvious, but this doesn't make sense. Was the gain all the way down on the amp to start? I mean, you sourced the signal from the same spot on the amp for both Amp and Head Unit setting, but something seems off. When you put the probes on and turned the head unit up to get the clip, where was the gain of the amp? If all the way down, then i am thoroughly confused. The reason is that when you moved on to set the clip of the amp, when you first put your probes on, there was little to no wave. Did you change the head unit volume down all the way? Was it left at 62? Seems like you did something in between testing HU and Amp for clipping that would help tie this all together.
@@jotay21 continuity error. I had two or three clips from two or three takes.
I'm very new to car audio, sans 35 years ago when I was a teen. I do have to say you make things easy to understand for old guys like me. I appreciate the effort you put into the videos as well as keeping all the fluff out. Well done my friend!
You sound just like me! I dabbled in this when I was young and then got back into it many years later.
This is the absolute best video I’ve ever seen for setting an amp
Thanks.
doug sends his love aka. soundman. we support you!
Thanks.
Maybe you have covered this in some updated videos, but youtube suggested me this one so I think I may chime in here with some advice.
- The aux port is the worst source for calibration since there's an additional preamp/ADC stage that you may be clipping, thinking you're clipping the output stage of the unit. Also another phone will have a different max volume.
- It's unlikely that any other input, bluetooth/usb/CD/Radio will have the same peak levels as a given phone, once in the digital realm inside the unit.
- Setting a -5dbfs test tone close to the clipping point guarantees that up to 5dB of usable (and used by artists) headroom will be clipped. Use 0dBFs
Here's to me, the proper way to do things, and how we generally do it in studios and live venues as sound engineers, but adapted to car audio environment:
- Use your ears to check for distorsion, as it starts bellow the apparent clipping level on a low res oscilloscope. The sine will at some point have a buzzy higher pitched sound, you want to stay bellow that level. To check this, set the gain of the speaker amp preamp very low, this ensures that you're very far from clipping the amp input stage and the speakers, then proceed with the next steps.
- Use a pure 0dBfs sine wave file via USB, CD/Bluetooth as it's directly digitally decoded and put the output volume of the unit to max. This ensures 0dBfs on the wave file will be 0dBfs on the DAC of the unit. If the manufacturer didn't brainfart the output stage, the signal should be free of distorsion. If it's distorting, lower the volume of the unit until it doesn't distort anymore and never go above that number in day to day use.
- Now you have the absolute maximum undistorted signal coming out of the unit.
- To set the gain on the speaker amp preamp, i'd then use the oscilloscope and refine with your ear. Your speakers may make have some distorsion at some frequencies that you may want to avoid by lowering the overall gain.
- Now there's absolutely no way in hell that the sound will distort unless the source file is already distorted.
No
Good stuff ... thanks! I'm gonna break out my Tektronix scope today as I'm setting up a 5 channel amp. The level will be set to the RMS handing power of my speakers.
Cool!
Tektronix scope you say??? You could hang a wet towel off the hardon I have right now for a Tektronics scope. You need it calibrated or just plain serviced you send it to me I'll use the chit outta it I mean return it within a week after servicing and calibration
I'm talking 14in Pringles can I could flex and lift do reps with a saturated towel with this hardon over a tektronix scope my friend. Whaaat that's awesome keep on keeping on while I go Meter out this fuel injection system to at least calm this curved and bent monstrosity of a pringles can. Plain massive and ugly but it throbs 4inches up in down in idle. Needless to say only the super whores have been having fun and I on every antibiotic known to man
quick question, i have a oscope and i setup my jbl a5055 which is rated @500rms at 2ohms on the monoblock side. I used a 40hz test tone at 0db and recorded a clean wave no clipping @ 37volts, doing the math that equates to 684rms could that be possible? i verified it with a multimeter (very good quality) my oscope is FNIRSI DSO-TC3 which again is decent enough?? i have two jbl a5055's bridged on the 4channel side (140watts rms x 2 bridged) , both of the amps recorded an identical 37volts with clean wave 40hz 0db test tone, clipping occured around 37.5 - 38volts
I just subscribed to your channel. You're right on the money with this stuff. I did a Google search for osciliscope fine tuning diy class ab amplifier. I saw how to set your gains and didn't know it wasn't a video of the internal components lol. I got stuck though because of how informative you are. Full of facts and math I love it. Also ima big car audio guy as well as my beloved home equipment. Anyways glad I found this channel. Can't wait until I finally buy a scope and can check certain capacitors to really fine to and build some SERIOUS QUALITY HI FIDELITY SHIT MAN!!! ILL BE ABLE TO.CHECK.STABILITY OF THE TRANSISTORS IM USING. SOOOOO MUCH FUN MAN LOL. I learned so much in the 30 to 45 mins I was straight glued onto your videos for the first time. Most of the formulas and convertions I already knew but I learned so much bout setting up errythang wit a MM. You really taught me some shit quickly my dooooooddd. Thanks man
My name is Matt by the way not Carol. Guess i never logged out of the account I made for my mother
I also want to build my own resistors because with all the amp equations you always have to select the nearest real value. Now of I could make my own half watt to 5watt resistors at something crazy like 56.8873 ohms I'd shit a brick n die of a heart attack mediately because I did something amazing there n all the big audio manufacturers straight Hite through the heart wit their invisible death lasers whenever the sensors on the Lazer cannons sense a higher fidelity product with THD .00000000000112% at full bore no clipping except I I wanted to "overdrive" a 4558 or something lol. Sorry for the rambling I eat sleep n breath this shit
When covid first hit i.couldnt afford a subwoofer amp for the house ya know. So I sourced some components from an alpine MRV357 THEIR 5 ch V12 model
The output transistors were BJT'S D718 and B688. With plenty I mean friggin plenty of small signal bjt and.bjt's all the way up from mw output to 20watts. So I went HAAAAAAAAMMMM AS FUCK on disassembly so hamam in fact I caught a hardon
Took a complimentary pair 718 n 688 and ran 100k5watt resistor between 718 base n 688 emitter with an inductor In-between. Coil was like 20wraps.ran 718 collector to 688 base n 718 emitter to 688 collector. Negative 12v supply and negative on a cut into aux cable( - input) to 718 collectoe to 688 base jumper. and negative speaker output came off of 688 emitter terminal and BOOM DID THAT PACK A PUNCH BABY. IF I WERE TO PUT IT IN AN ENCLOSURE AFTER FINE TUNNING WITH SCOPE PPL BE LINED UP SUCKING DICK FOR MY SINGLED ENDED 2TRANSISTOR SUB OR WHATEBER DA FUXK YOU WANT AMPLIFIER
Thank you for the video, it is very helpful. I was wondering when I'm setting up my gains on a subwoofer I only have access to disconnect my rear speakers for testing. Will this process work if I set the fade to the rear while setting the gains on my monoblock amp with the oscilloscope?
I would test all channels. Set the gain from the channel that is clipping lowest. So for the front or rear use the channel that clips first, left or right. That way when you turn your volume up neither channel clips. If you were to use the higher clipping channel it would be clean but your other channel might be clipping. I hope it makes sense.
Smart!
@@DIYAudioGuy Man you weren't kidding when you said you try to read all your comments. Thanks.
When first probing the output to find head unit clipping level, do you start with amp gains at 0?
Where is the gain when set the HU volume? You don't mention this in the video. Does it not matter?
Start amp gain off when setting HU volume. Then adjust the gain until there is clipping
I usually set my gains with a 0dB sine tone as I listen to a lot of non-mainstream trap/EDM. Is there something I can use to figure out what the maximum dB is of songs that I listen to, or can you recommend a dB sine tone I should use for my requirements? I know -5dB is the default but I'm not sure if this might be too much or too little and I'm really looking to maximize my gains. Thanks so much for any help you can give!
You might be able to play the song using audacity and getting the levels that way. But I think you've made the right decision to go with the zero DB tone. Especially if you got bass boosted music. One thing you can do is try a -3 DB tone and see how that works.
I just shat my pants n nutted straight shocked n pleasure at the same time. The word bassotronics my my Nutt hair stand up
Hello!
I have a weird issues of my sound, whatever comes to your mind, I've already checked it.
I have Shit bass from subs.
I tested all Components of Audio, wires, rca's, subs, amps, Head units itp.. My issues:
- Different bass quality (in feeling presure too)
- Different Output voltage from head units (Kenwood 7200dab new, Alpine cde 178bt)
- Voltage on amps body hecked with: (Multimeter one wire to ground terminal amp, next wire to body amp (screw) i can have voltage on all amps dependent of instaled amp location. Now i have to 2volt on my sub amp, before 13v it always drops while reading voltage.
- After changing the port of subwoofer to 25hz, i hear a sound degradation from vocal (music),
sometimes moving the windows can improve the bass but very rarely.
My score is on car closed, 151 db 37hz from 15,5volt to 12,3v voltage drop. but i dont hear and fell this power :/
I fight with this issue about 5 years in two mazda cars...
If bass is ok, bass can lost after next enigne start.
I recently sold my equipment Clarion sw 3012 and Crunch mxb 480, about 120 watts rms from this sub, and it played well in Renault Clio 3. And there was no problem with the sound at all...
This voltage on amps body can degrade sound quality, mallufuncioning Head units? i added ground to amps body, i have 0,000v but problem of sound is still
Can you help me?
Mazda 6 2007r
I forgot to add: all settings of Hu's, amp gains settings, i no hear differences...
Any electrical upgrades? Alt, batteries etc?
@@ericdayman3568 Yes, everything is better. Yesterday i finished correcting instalation, distribution block, head units, amps from dist point. All grounds point fresh cleaned. Effect? not changed, subs blowing, sound bad...
Its like Noise, Gain loop. Or EMI interfence.
@basserex4991 are you using the factory wiring from amp to speaker? I remember my buddies 2008 Mazda 3 had a similar issues. Everything sounded like shit, super distorted and gainy.
I am using DMM method from years never had problems but today when I changed sub I wanted 40VAC voltage but my DMM is not heading ahead 33VAC don't know my DMM went bad or my head unit isn't sending enough signal even though it has 5V pre outs. But what I noticed is my DMM tiny wires went super hot after trial and error so I guess my DMM isn't accurate anymore! Please guide me on the same
You might just need some new test leads. But, since you do this a lot, I think you should probably upgrade.
amzn.to/3pHODyC
amzn.to/31OSx0z
I have a question. Plus, I love your videos. They not like most. You give real numbers and proper facts, that is fantastic, and what I need, the right information. I am still learning all this car audio stuff.
I have a 2ohm 800 watt car subwoofer setup, running a 1500.1 D amplifier. However, my amplifier max voltage is 6 volts and I need 6.7 volts to make 800 watts (goes over a bit). According to my equation. Can I set my LOC2 at 6.7 volts and be fine or have to stay at 6 volts and calculate that extra .7 volts to my 40 volt (makes 800 watts) setting on the amplifiers gain?
Thank you very much, can we adjust the high and low frequency with an oscilloscope too?
Yes!
@@DIYAudioGuy How do you do it?
@@Navylus If I was to guess (which I totally am), I'd probably do 2kHz for mids and 12kHz for highs? Or maybe look at the speaker specs and just go halfway to what their frequencies response is.
First...thanks for this! I just installed a 4-channel amp in my truck and need to set the gains. Question...when setting up the HU, do you recommend setting the equalizer to a flat signal or to the settings that you would most likely have it at when playing music?
Yes, set it all flat, then when EQ'ing cut out the loud frequencies.
Hello, I have a question. On minute 2:57, I see where the wave clips (flat spot at top). I have the Abestop 2 in 1 oscilliscope, but I can't seem to get the ceiling to lower to where yours is showing. The waves go all the way to the top of the screen. I tried changing the range, but it still doesn't lower. I understand the time adjustment to space out the wave, but not lower the ceiling. Of course the instructions doesn't provide any info on that. Thank you.
I’ve got a 21 f150 with the B&O system. I’m adding a aftermarket sub. I bought the O-scope from your video. Do you have a video of finding the clipping point of the amplified head unit? I can find a ton of videos on testing a non amplified head units.
Yes, just probe the output from the factory amp -- I have never seen a gain control on a factory amp. All of that is set up from the factory.
Is there any way to set a 4 channel amp gains by ear? If so what tone should I use?
Back in the day installers set everything by ear. I would not advise using a test tone to do it since it will sound quite unpleasant.
Hi I have installed in my car a 4-CH amplifier that drives a pair of 2 way speakers (woofers and tweeters) and an other 2-CH amplifier that drives a woofer. So to tune correctly the gains with the O-Scope I should run the below test tones:
1) 50 HZ, - 5 db test tone for bass
on 2CH Amp
2) 1000 HZ, - 5 db test tone for mids on 4CH Amp
3) ???? Hz, - 5db test tone for highs
on 4CH Amp
What test tone should I run for the tweeters (highs)?
I did one try with O-Scope and tuned gains at the maximum allowed values of the 4-CH Amp according to the 1000 Hz test tone as you mentioned but I noticed that I have disortion in higher frequencies (8000 Hz and above).
What should I do for the hights?
Thanks in advance!
You can use 1,000 HZ to set up the tweeters -- the speakers are typically not connected when you do this.
I kinda understand but I don't understand. On my amp, there are 4 different twist style knobs and they all have different things and idk what to set each one for.
I see the gain but what about the others? What should they be set to?
You might not need to use them, it will depend on the rest of your setup. If your head unit has a crossover then you just need to set the amp crossover to it's highest frequency so that it will have no effect.
Nice video just got the LM2020, I seen other video with DMM and the head unit should be flat , zero settings on treble bass and Mids, my concern is do I leave those setting there? If I want more treble will that change the clipping point from my head unit ? 26 on my volume is the point of no clipping 27 will clip
When setting EQ the rule is to always cut instead of boost. Only boost as a last resort. So if you need more trouble you cut the bass. Now if you use a zero DB test tone you've got plenty of room to boost the treble before it clips.
@@DIYAudioGuy thanks for the fast response and the help !
What are your settings on oscilloscope? Im using a different brand. How do i show clipping.i have a 4volt output on my HU and my oscilloscope goes from 2.5 to 5V theres no in between for 4.
How’s it going brother!
Been learning so much from you and your vids, thank you for your time and effort!
Got a request: I’m someone who has a factory head unit, an Audiocontrol Lc2i, an Audiocontrol bass restorer, and an aftermarket amplifier. I’m sure I’m not the only one with the extra bells and whistles :)
Can you please teach us where to start checking for clipping, and where to go after each step until we’re done tuning for clipping?
Thanks again brother!!
Great idea, not sure how long it will before I can get to it.
ok you set the gains on the Amp, but what about the speakers? Are they not taken into consideration at all? What if the speakers I'm using can handle less than what the oscilloscope showed for the amp?
I have some videos on that, this is a good one: th-cam.com/video/c-UTA59pfPA/w-d-xo.html
Loving your bodies after a long break from car audio. If you use a 1k test tone for muds and highs and say have you crossover set at 80-100h will the lower h distort/clip first?
Honestly, I am not sure.
@@DIYAudioGuy
Maybe an oscilloscope test and video is in order? Every video I’ve watched says use a 1k test tone. Maybe there’s a better frequency to ensure you get the best out of your amplifier for sound quality? Maybe 1k needs myth busting?
Could be a job for you, I’ve found your videos really educational and I really enjoy watching them.
Keep up the great work. 👍🏻
Also apologise for the previous spelling errors,
I was watching TH-cam in bed on my phone without my glasses on 😂
Hello can you please tell me how you checked your phone for clipping? I just ordered the same oscilloscope of your link. I will be connecting to the head unit via Bluetooth with my phone.
I just turned the volume on the phone up all of the way, connected the BT to a device, turned that device up about half way, and played a test tone. I tried it on several different devices, I also checked the headphone out.
Good video. Can u answer one thing for me. How is this accurate without a load on the amp? The rail voltage will change with a load applied. Could you do this with resistors or a speaker hooked up to see if it’s the same?? Love the channel.
I think Barevids did a video showing that a load will impact the results. So you are correct.
I used the tweeter method barevidz and a few others have videos on. I’ve tried both ways and it definitely clipped earlier when loaded.
@@gregblau8082 Makes sense. I actually just got this same dmm. Tried with and without speakers on a head unit and it was the same. Have not tried on A sub amp yet. Would be fun to test how far off it gets the more power you got.
Question: I have a powered(amp built in) JL sub. This method or the oscilloscope wouldn’t work unless I removed the speaker and measured at the wires inside the box, right?
This video will help with adjusting gains on my separate 4 channel amp though!
Correct.
If I was wanting to run 4 ohms bridged would I put the O scope on the bridge connections?
Yes
I have the Alpine SA55V. A 5 channel amp. Where I can bridge the four channels down to 2 channels while still having channel 5 for the sub. The question is would I still use the 1000h tone for the bridge mode since I’m using them for higher power components?
Yes -- Use 40 hz if setting a sub and 1,000 hz for everything else.
Question. It looks like you found where the head unit clipped by probing the amp at the speaker outs. Am I crazy to think that it should've been tested on the RCAs? Wouldn't probing the speaker outs be show results for the amp? If that's not the case, then was the gain set all the way down when testing the head unit for clipping?
You can test either the RCA's or the speaker output. If you send a clipped signal in you will get a clipped signal out.
What’s your opinion on the smdd +1! That’s what used to tune my audio! Sounds great! ✊🏾🤟🏽! Great video 💯
It's a good tool, but to expensive for a hobbyist or DIY'er that may only use it once or twice a year. If I were a professional working out of a shop I would get one.
@@DIYAudioGuy 💯✊🏾🤟🏽
Hi, I think i'm misunderstanding a step in this "process" because something isn't making sense to me. You set the headunit so that the peak is just starting to flatten out, but then I don't understand what "volume" you set the headunit to when you start adjusting the gain. Because wouldn't where the gain starts clipping change depending on where you have the volume of the headunit? And, if you start adjusting the gain when the headunit is almost already clipping, wouldn't the headunit start clipping immediately after you start adjusting the gain?
The idea is to turn everything up to just before clipping that way you have the strongest signal possible going into the amplifier.
@@DIYAudioGuy so that's 75% on the Head Unit??
Should I set my crossovers settings first or after setting the gains ?
Set the gain first. Disconnect all speaker wires so that you don't blow your tweeters.
Awesome, thank you .
Tight like a tiger mode😁😁😁
THanks!
How do you check the phones clipping level? Mine doesn’t have a headphone jack
You can do that through the amplifier or head unit. Sit everything to a moderate volume level and ensure that nothing is clipping. Then crank the phone all the way up and see if the wave form shows clipping.
@@DIYAudioGuy So is it technically impossible to blow your speakers by setting gains like this?
@@phreaktor No, you can still blow speakers, you just can't blow them by clipping them.
I tried this method tonight in hopes of being able to Bluetooth the sine wave into the system via TH-cam. My sine wave appears to be made of a wave itself. Any clues?
Not sure what’s going on.
You can see a wave riding along the wave? I have seen that before and I am not sure what causes it.
I see different methods of setting gains and head unit volume. Most people say to turn off your eq settings, bass boost, loudness, etc on both the head unit and amp before setting gains. Others say you need to set all that first so you can set the gains and your amp/head unit won't clip this way unlike if you set the gains with everything off and then added them afterwards.
So which is correct?
Those that say to set EQ before setting gain are wrong because they are setting their EQ incorrectly. When setting an EQ you cut the loud parts and only boost if it is a last resort. Their advice is based on a "two wrongs make a right" world view. The bass knob/level is a little different. Most of these need to be up all the way. Same bass knobs are actually bass boost controllers -- I think Pioneer does it this way. In that case you want it set to flat.
Don’t use loudness or bass boost,but like EQ settings in the shape of V,if you set gains flat wouldn’t it cause distortion when you adjust?
So just a quick question to find my watts using a amp clip meter and oscilloscope do I times amp *vmax or amp*vrms?
RMS
Why did you use a -5db track? I thought were suppose to use the 0db track. I have kicker marine speakers and just ordered that scope tool since I couldn’t get the voltage anywhere near what JL audio said it should be for their amp by using a multimeter. Hopefully this Meath is works!
That is called gain overlap. th-cam.com/video/20XiqMBPIks/w-d-xo.html
Another question… I have a marine amp and Bluetooth source unit. Do the same rules apply?
Can you clamp the ocilloscope probes inside where your speaker wire connects or should you use the tip of the probes on the top of the terminals?
Yeah, just don't bend them.
@@DIYAudioGuy okay thanks again
So which tones 0dB or -5dB is the best for setup? For play loud and clean with nice bass
Use a zero db tone for everything but the amp. For the amp set it to taste. Most music is -5 db and I have found that -5db is good for mids and highs and -7 to -10 is good for subs.
0dB when setup head unit with gain on amp on minimum? And then if i want setup amp - 5dB for midbass and -10dB for sub? Right?
Great video but with all this information im still a little confused with one thing. I set it so my amp wont clip but now confused since one set of speakers rms is 60watts and the other set is 90watts rms coaxial speakers. Is adjust the rms somehwere else? I have kicker cxa360.4. And speakers are jbl gto 939 and 629. Any help is greatly appreciated
The amp rating is based on the amount of power the amp can produce. The speaker rating is based on the amount of power the speakers can handle. So set your gains using the lower of the two numbers.
I have some updated videos that may help. th-cam.com/video/c-UTA59pfPA/w-d-xo.html
@DIY Audio Guy what do I set the range and time?
Just adjust them so that you can see the wave. Think of them as kind of a zoom control.
Sane thing as the mustool? Looks like a few on Amazon that look just like it.
There are several different brands out there that all look to be about the same.
The power and ground are really close on my amp. Can I use a short length speaker with clips to measure
If I understand your comment correctly you then yes you can.
Hi was wondering can you tell me if this is correct?I have head unit connected to Amp.With gains on amp turned all the way down,Connect o scope to one of the front speaker connections.Then turn head unit volume up untill the o scope shows clipping.Here is were i am not sure.Once i find the clipping volume on HU and turn it down till its not clipping do i leave the volume at the level and then starting turning up my gains?Or do i turn volume back down on HU and start turning up gains?Thanks
I have the same question. Did you ever figure it out? Wasn't sure if he turns the head unit all the way down or leaves it at volume when setting gain on amps .
@@Bking7string Keep the Head Unit at the volume just below clipping then adjust the gains on the amp.
After watching your videos, I bought a small oscilloscope and set my gains. I found my head unit would not clip even with volume maxed out (50). I set my gains with the head unit all the way up. I set both a 4 channel and mono amp for my subs. It didn’t n take much gain to start clipping, probably about 1/4 turn. Does this mean I am not getting the full power available from the amp?
Nope, that is what you want! The goal is to get the loudest possible clean signal going into the amp so that you don't have to crank up the gain.
@@DIYAudioGuy that great news. I am just starting to understand how all this works, your videos are very helpful. Thanks for getting back to me so quickly on one of your older post. You have a new subscriber.
If I ever change my head unit the only thing I have to adjust is my gains, right? Do you have a video on setting up an impedance converter ?
Yep, just have to adjust the gains to match the new head unit since they are all a little different. Not sure what you mean by an impedance converter.
@@DIYAudioGuy sorry that was a literal translation of how they call them here. I meant a line output converter. Those have knobs too.
@@amedsoprano kicker has a video on it.
Does this method work on full bridge amps like the taramps
Yes.
If I am checking the clipping point of a factory head unit with a factory amp, do I check it at the speaker before or after the amp? 2011 f150 raptor with Sony system for example
Both, the seagull going into the amp needs to be clean as does the signal coming out.
Just be aware that the signal going into the factory amp might be a data feed, so you might not be able to read any kind of signal off of it. It's not unusual for newer cars and high-end cars like your raptor to have that "feature".
@@DIYAudioGuy ok. Thank you
I have installed a 4 channel amp but i am going to have a 2 ohm impedance for my mids. Would i still be able to set the gain without my speakers connected?
Yes
@@DIYAudioGuy wouldnt my gains differ with a 4 ohm vs a 2 ohm load?
I assume you set the volts to DC on the oscilloscope when setting amp gains? Another channel had said to set it to AC volts. Which didn't make sense as the car's electronics run on DC.
No, set it to AC.
@@DIYAudioGuy Ok, thanks
I saw the same thing, and as I'm just trying this method for the first time I hoped someone else asked this question.
How do you disconnect the (non-sub) speakers from the headunit to set gain on the headunit in cases where the wiring harness to the HU includes power and speakers?
Just wherever it is the easiest to get to. Since it does not sound like you can easily connect the probes at the harness behind the dash it might be easiest to do it at the speakers.
I have 600W RMS @ 2 ohm mono amp! However my subwoofer is rated at 400W @ 4 ohms, wouldn’t my amplifier clip over 34.64 volts (√600W*2Ω= 34.64V)? If so, with the subwoofer above my amplifier will output at 4 ohms √400W*4Ω= 40v. That seems a bit high.
I was thinking because my mono amplifier is a 2 ohm stable class d amplifier, shouldn’t the formula technically be √400W*2Ω= 28.28V and that shouldn’t be clipping cause 35V+ should clip cause that’s max voltage output out of the amps channels? Or am I just overthinking 😅
You will run the amp at 4 ohms since the sub is 4 ohms. So use the amp's 4 ohm power rating or the subs power rating, which ever is lower.
Aren't you supposed to use 0dB when testing for max volume on the HU? Then use -5 or -10 when setting gains on the amps?
Most music is recorded at -5 DB, so that is probably the best test tone to use. If you use a 0DB tone you leave power on the table. If you want to push your amps and you are not afraid of the occasional clipping then go with -10 DB. Does not matter if you are working the head unit or the amp.
What would be the proper way for highs
Exactly the same, just with a 1,000hz tone.
What about using load resistors to simulate a load on the amp ... that will affect clipping point quite a bit.
Yes it will. Not sure by how much, but it will.
How do you test a i-phone as source for clipping level?
Connect the phone to the head unit, turn the phone all the way up, set the head unit to about half way up, and then measure the output of the head unit for clipping.
To set the head- unit shouldn’t you use a 0db test track?
If I recall correctly CDs are recorded at -5 dBs, and that is the standard. So for that reason a -5 dB test track is probably the best one to go with. But people use different test tracks for different reasons and it's probably not that big a deal.
So - what volume is the head unit set at when doing all this testing? 75%?
Use the oscilloscope to find out where the head unit clips.
@@DIYAudioGuy Using the SAME speaker outputs from the amp correct? And play a "test tone" while doing so. I bought the same Oscilloscope you have
@@patricklim3703 Yes.
@@DIYAudioGuy See - this is where it gets confusing.....SO if I am supposed to use the SAME speaker outputs that are on the amp....is it safe to assume that all the gain settings on the amp need to be at their lowest position? Then - turn up volume on HU to see where clipping occurs, then back off a little to no clipping on sine wave. Then - play test tune at THAT volume on the HU AND slowly turn up the till clipping occurs, then back off a little. DONE. is that the right sequence of events?
@diyaudioguy The math makes sense for 4ohms but at 1 ohm its different. My amp will do 44.7v cleanly which would work perfectly to my amps spec of 500 watts at 4ohms! When done with 1 ohms my target voltage would be 34.7 which would equal 1200 watts which is my amps rated power at 1 ohm but if I tune using a oscope my amp clearly puts out 44.7 watts cleanly so tuning with a oscope means im getting too many watts at 1ohm? Just curious why the math seems odd here and almost like I shouldnt use the max clean output when doing 1 ohm thanks for any advice!
My best guess is that your amp can produce more than its rated power.
This Does work until you get a big amplifier the waves are too big and the current is too powerful for you to be able to see the sine wave on a toy oscilloscope. I was setting my JP 234 which the oscilloscope did give me a little bit of an idea of how clean the signal is coming out of the jp. It's a little dirty. Okay so I can't see the top of the sine wave you can motivate one side all the way down so you can see just the top or just the bottom from the middle and it's so much power I can't see it
Is this process different with a 5 channel
Nope.
I have this same one and I can't get my waves to change nor ready my ac voltage
Hi I have 4 midrange speakers on a 500.4 Amp. Where in the Amp can I adjust to make my speakers alittle louder . On my headunit when I turn volume up to 25 it is not loud enough
I suppose you could turn the gain up, but it is better to use the gain control to match all of the parts.
Oh ok so if I want to turn gain up I would turn the knobs on Amp that says Gain
@@jesuszuniga1257 Right, but the gain is not a volume knob. The idea is to set the gain on the amp and then leave it.
Oh ok and how much should I adjust it so it close to max just want to adjust alittle. Should I lower my volume on my headunit while adjusting gain
@@jesuszuniga1257 there's no way to know how much you need to adjust it without a meter or a scope.
Why is it that when figuring out where the head unit clips you had a sound wave but when you went to set the amp gain that sine wave was gone and in order to get it back you had to turn the gain up. Am I missing something? The oscilloscope was on the same two terminals for both the head unit test and amplifier test, so why did the sine wave go away when beginning to set the amp gain. The head unit was still turned up.
Continuity error. You're the only person that's caught that. This video required multiple takes. At some point in between takes I had turned to the gain all the way down.
Where was the gain setting when testing the head unit sound wave. I understand when checking the amplifier sine wave you started with the gain at its lowest setting but what was the gain setting on when first checking the head unit? Wouldn’t it need to be turned up a bit in order to even see the sound wave? Am I over thinking this? Thank u for the reply
Can you do a video on how to calculate a port, tune etc using pen and paper or along with a free sub box calculator? Anything but winisd. Winisd is confusing.🤦🏿♂️🤦🏿♂️🤦🏿♂️ Preferably pen, paper and a calculator. I love all your videos. I’m learning.👌🏿👌🏿👌🏿🔥🔥🔥
WINisd is the best free tool out there. It is confusing but it is much easier than pen and paper.
@@DIYAudioGuy ok gotcha 😬😬😬🤦🏿♂️🤦🏿♂️🤦🏿♂️
This may help: th-cam.com/video/yZNeYBYGRKk/w-d-xo.html
@@DIYAudioGuy ok thank you
One thing, your background music is too loud and distracting.
But your info is solid.
You should check out some of my more recent videos. I've been able to get some better microphones and better editing software.
Why do my amp cut off certain speakers when i set gains using -5db & -10db but when i set gains using 0db my amp never cuts off?
Probably because your amp can't produce the higher voltage at the negative 5 and negative 10 DB settings. Make sure you have everything wired up correctly. That's the kind of thing that happens when you try to run a 2 ohm stable amplifier at one ohm.
I've read two ways of doing this. I know some use 0db or say -5dB test tones. And it was said in different places if you use a -5dB, you use that to check when the head unit distorts. Then you use the -5dB to also set the amp gain level.
Then someone said if you do that, then that is like having a -10dB setting on the system. And so they said you should always set your headunit volume via 0dB, and then you can use whatever to set your amp gain levels to, i.e. 0dB, -2.5dB, -5dB, etc.
I'm wondering, which way is the correct way? I'm going to guess it makes sense to just set the head unit volume via a 0dB level tone, and then pick whatever for the amp gain level. I plan on doing that using 0dB on my head unit and set it, and then putting a piece of tape on my amp and marking amp gain knob at 0dB, -2.5dB, and -5dB test tone, and then playing with the knob to figure out where I want it via listening to music
I'll probably start on 0dB on my amp knob, and listen to something soft like Tom Petty, and if I don't have to max the volume out on the head unit, then I'll probably leave it. But if I do, then I'll turn the amp gain knob to my -2.5dB mark and see how that goes.
I've never really thought about it, I'll have to look into that.
@Natural Creature I ended up buying a DD-1, which I later sold. But I used that to set my gains, I did tests on 0db and -5db.
I found 0db was at the first mark on the amp, and -5db was at the 2nd mark. I did tests and found I could leave it at 0db since I never maxed the volume on my head unit when listening to my test music on the 0db mark.
Also, when I used the DD-1, I had my Alpine head unit volume set to max.
Using the DD-1 was so easy. I do recommend buying one used, use it and get a ultra fine silver marking pen to mark dots of 0db and -5db on your amp for future reference and then sell the DD-1 when done.
Thank you 🥰🥰🥰🥰🥰
Glad to help!
You may be the first who can *actually* do a how-to for WinISD and have it understandable. I have watched so many videos on WinISD and it is still confusing. When the T/S parameters are entered does WinISD spit out "a" box specific to the numbers or is WinISD used to manipulate the T/S numbers to get several different custom boxes????
No need to answer - it is just one of the MANY WinISD questions
Good questions!
Here you go! th-cam.com/video/yZNeYBYGRKk/w-d-xo.html
How about setting the gains on your videos? Some of them are too quiet and some of them are too loud.
Take a look at a more recent video. I think you will find the audio quality is much better.
If my door speakers can play as low as 80 hz, why use such a high pitched tone to set the amp?
Because that same speaker is going to have to reproduce frequencies higher than 1000 HZ. So you're trying to find something that's a reasonable compromise between all the potential frequencies it might play.
you assumed a 4 ohm load to calculate power in watts. How do know the meter is a 4 ohm load?
When measuring voltage the meter does not put a load on the amp. There should be very little resistance. I'm not a multimeter expert, so I'm not sure how they go together and what kind of resistance they have. In voltage mode the meter just measures voltage. Voltage isn't power, there's no work being done. If you run a given voltage through a 4 ohm load then you get watts, that's power. So if it were hooked up to a 4 ohm load you use the formula to calculate the power in watts. Hope that makes sense.
Let’s do a hypothetical. Say you are setting up a gain knob on 4 channel amp and the only tool you happen to have is a multimeter. You would obviously use a 1000 Hz test tone at around -5 dB. But just out of curiosity you play a 50 Hz test tone at -5 dB. Would you get the same voltage reading? From what I understand and have experienced you shouldn’t right? Which leads to my next question. The operating range for a multimeter is around 50-60 Hz because our power outlets in the US are around 50-60 Hz. Wouldn’t that make a 1000 Hz test tone inaccurate? Please correct me if I’m wrong I want to learn things.
It SHOULD be the same voltage, assuming all crossovers are off, or out of the range that matters.
@@devnull182 hmm maybe I did something wrong then. I’m gonna try again when I get home :) thanks!
Great questions. I would need to do some testing and research to give you an adequate answer.
@@TheDeluxe4O I think however, that what I Said is only valid when the speakers aren't connected. Because if they are connected, the impedance depends on the frequency, which will in turn change the output power of the amp.
@@devnull182 so I just tested this and it seems that the voltages are different when I use the 50Hz test tone and the 1000 Hz test tone. Any idea what going on? I made sure I didn’t have any filters on the amp.
1000hz test tone to test deck output?
Yep
Can anybody help me build a Balanced line driver for some Old School Soundstream amps and crossover? I have amp schematics and Pin out for the line driver, but all of the schematics I see are from home audio. I'm stuck and don't know where to look. If I'm in the wrong place and being rude, all apologies.
Never be afraid to ask questions. I don't have the slightest idea how to help you.
*0:40** Wouldn't a calibrated pink noise be better?*
If you did that each individual frequency would show up as a different waveform on the oscilloscope and all you would see is fuzz.
Pink or white noise is best used with an RTA so that you can visualize the frequency response.
Just to be clear for any newbies, all pink noise is not the same. It's unfortunately gotten rather generic in meaning.
A true calibrated pink, starts in the infrasonic, and goes slightly into ultrasonic.
ie, beyond human hearing.
I've seen (on the scope) some slump shouldered pinks that don't get going til 120ish HZ, and have very little energy after 15k.
A good one, should almost look like a block of signal equal db at every freq.
And definitely don't download your pink from YT and it's compressed hell of audio.
I can't get a clean signal at all on my JP 84, shit is squiggly. Alpine cda147bt is good at 26/35
That is odd, my JP84's are clean. I have a similar head unit, I can go all the way up and still get a clean signal from the RCA's.
@DIY Audio Guy yes, I even tried the volume know up more. And these are one of the olders that are still clean. But 1k test for the jp 84, whole sine wave is squiggly. Prior to that the deck was clean @26/35. It plays fine. But the signal is just dirty on my amp. I'll double check it in a bit
How about a deal?.....get a bass van and I will subscribe!
😄😄😄ok.
@@DIYAudioGuy fine you twisted my arm! I will subscribe anyway! just get yourself a bass van!
you don't need a resistor to load the amp
That is a hotly debated subject.
ok thank you
@@DIYAudioGuy
Good night need some help please
That is a great question, join us on our next live show and we will try to give a detailed answer: bit.ly/3PYKG5P
Don't you mean "17.3V" instead of "7.3V" @3:10.
Yes.
According to TH-camr DAmoreEngineering the correct formula for calculating the "Real Power" of an AC circuit with a reactive (non-resistive) load is:
V(rms) x I(rms) x cos(Φ) (where Φ is the "phase angle" or the phase difference between the voltage and the current)
See his video here: th-cam.com/video/qwxlnSDv9wY/w-d-xo.html
Any thoughts?
th-cam.com/video/GuK0FLijYDE/w-d-xo.html
MAN YOU DID NOT SHOW THEM HOW TO PROPERLY SET UP GAINS WITH AN OSCOPE. YOU SHOULD HAVE SET THE GAIN WITH A LOAD ON IT! THAT IS THE CORRECT WAY!
I disagree with your flagrant use of capital letters but I agree with your comment. Clipping point will change when the speakers are connected. I've tried this.
You are correct, Sam over at Barevids showed this. Easy fix. Connect a load and do the same thing.
I can’t focus on what he’s saying with such loud music . I am leaving