What Happens When You Wire Speakers Backwards?
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- เผยแพร่เมื่อ 16 พ.ค. 2024
- Have you ever wired a speaker backwards? What happened? See and hear it for yourself in this video.
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LINKS:
Loudspeaker Animation: animagraffs.com/loudspeaker/
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00:00 - Opening
00:29 - Experiment #1: Speaker & Battery
02:25 - Experiment #2: Transducer
03:51 - Experiment #3: DAW - Sine Wave
04:24 - Experiment #4: DAW - Snare Drum
05:03 - Experiment #5: DAW - Multiple Speakers
07:30 - NEXT VIDEO: • Everything You Need To...
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If you wire your speakers backwards and listen to country music, the guy actually gets back his horse, his job and his wife
LMAO 😂
Yes, but now his existential angst is too much to handle, thus Emo is his new jams.
And if you are listening to Blues music, all the above plus it stops raining.
Plus, he quits drinking
you forgot his truck
I learned about the importance of polarity when I was young. I received a ghetto blaster for xmas and I was shocked that AM radio sounded so much better than FM. AM was in mono and only came from the left speaker but FM being stereo came from both. My natural curiosity got the better of me and I opened it up 2 days after getting it. My mother was furious. I had no idea what I was doing or should be looking for but I knew the difference between positive and negative and colour coding. I saw the left speaker was wired white to + and black to - which seemed normal to me. But the right speaker was wired white to - and black to + which seemed wrong. I had already been soldering for a few years so I desoldered the wires from the right speaker, switched them and soldered them again. I put it on FM and was amazed at how good it sounded. My mother was so happy that it worked but still never gave me any credit for fixing/improving my gift. For years she would say "Do you remember that xmas you took apart your radio?" and I would always ask her if she remembered that not only did I put it back together but that it was better than when I had taken it apart. Never got any credit for that.
Hope you kept that thought process in your older years. You did what 99% of the people won't bother with these days and just throw it away.
@@PauldeVries I still regularly take things apart. Often only to see what's inside. I've gotten a LOT better at putting them back together again as well. lol But yes, 99% of the time I will try and fix it. I'm cheap and would much rather spend a couple of bucks on parts and a little bit of time instead of tossing it out and replacing it. That's one thing my grandparents taught me: Repair it until it can't be repaired any longer and then salvage whatever parts you can and repurpose what can't be salvaged.
@@Enjoymentboy Yes, things are more useful than meets the eye sometimes. Hope you gave yourself credits for that ;)
Pretty sure she would have given you credit if someone had thought her how and why to do it. Don't think she intentionally held back on giving you credit. But yeah man, sometimes those unimportant moments for adults can become lifelong memories for kids.
@@exshenanigan2333 well said
Having some education in electronics and a half century experience with home stereo, I can't say I learned from the video. But oh how I enjoyed seeing it explained so well. This young man has a gift for explanation.
I knew this but this was the absolute best depiction of the principal I have ever seen. Well done!
"Why are my speakers not speaking"
"They don't agree with each other'
As a musician, this is genius
Putting them in different closets in the dark for six months may cure this.
@@johnb3141cancel culture is literally destructive interference ...
Might try this with my gf, thanks. Hope she doesn't come out gay. @@raymota4515
I would have thought that disagreement would cause a 6db increase in sound level.
Years ago, I found I had accidentally wired one of my two subwoofers in reverse (in my mobile DJ rig). When I saw how I had screwed it up, I laughed so hard! I had been struggling for several months with my system - asking myself, "Why can I hear the base coming out of each sub when I stand right in front of it but when I move to the center of the dance floor, I don't hear or feel it?" No amount of EQing or compression made any difference. When I saw I had the cable to one sub wired backwards (positive to negative and negative to positive), man oh man, I was relieved. I still laugh today thinking about it.
So you experienced wave cancellation by first hand 😂
I worked on a recording system that sounded perfectly fine but when you tried to record you got nothing. Someone wired one of the inputs backwards so the mono signals from the mic were being cancelled.... The tech who installed it couldn't figure it out for 2 weeks.
@@BrettDaltonLOL!! It happens to the best of us
Haha that's a good laugh. I mean in the sense that we've all made simple mistakes but genuinely bothered us. Then we happen to stumble upon the solution like it felt sorry for us lmao
Bro’s made of positivity👍
When you listen to the initial hit of a kick drum there is a definite change of sound and feel with a single speaker wired with reverse polarity. Especially with a PA sub system that covers the 25Hz range. If everything is wired correctly you should feel the air hitting your chest. If the sub polarity is reversed then the kick drum completely loses it's impact. This because the first positive peak of the sine wave is the largest and sound pressure waves in compression have better projection than ratification of sound waves.
Absolutely correct. I was going to post similar comment. If that would be no difference at all then drummer can put his kick pedal in front of bass drum and play that way. But nobody ever played such way in a music history for obvious reason. You need LF sound kick to propagate toward audience. However I agree that it would be no difference in mid and high freq ranges.
very important !
This. Difference between a pressure wave and a lack of pressure wave.
If that were remotely true JBL would have never wired their bass drivers reverse polarity.
@@keithmoriyama5421 😂
From a guy who got his MECP back in the early 90s, which is pretty much being a professional in creating and building high-end stereo systems in automotive and also in homes. And I have to say this may be one of the best breakdowns in the simplest forms to make sense of this. If you are a beginner, this I think is a great example to get the basic idea. I think he did a great job at this, and realistically that is what a teacher should do
Now on a little side note, when I first started out, I had two 12-in subwoofers side by side in a hatchback, 3rd gen Camaro, and I wired the subwoofers positive to negative positive to negative, remember mono amps and dual voice coil subwoofers we're not as accessible as they are now. Regardless, this does help simplify my example. So I'm testing & tuning my sound, & when i had one sub connected it would always be louder & deeper than when adding the 2nd. It was technically wired correctly. And I just couldn't figure out how this was possible. Long story short, eventually I learned how the Box the subs are in are built, the environment they're in, and other factors can actually affect phasing. Somebody told me to reverse the positive and negative on one of the subs, negative to positive and positive to negative, and I heard the immediate difference.
So if you are putting together either a home and or car audio system, be mindful that this could happen. And you may want to try something like this. Obviously when you get into much higher end audio systems there are a lot of equipment to help you through this.. some of the tuning equipment can pick up this type of issue and where it possibly is coming from, all types of crossovers, equalizers and amplifiers that can adjust phasing for individual channels, etc etc, and sometimes still you have to do it the old-fashioned way
This how noise cancelling systems work, listen to the unwanted sound and invert it add back to cancel the unwanted sound dynamically.
Yes, except it has to be done fast otherwise it wouldn't work
Is it done fast or do they guess what sound will come in the future? I know some years ago it was just trying to predict the sound, but maybe nowadays devices are fast enough to do it on the run
@@tatomar001 Pretty sure it's a combination of both
@@tatomar001 They passively listen, basically you have microphones facing outwards recording the world, then some clever signal processing analyses and inverts the signal and adds it to whatever you want to hear. When playing this new signal most of the noise from outside gets canceled out, leaving only the intended audio track. This is called active noise cancelling (ANC), there is also passive noise cancelling which just plays some grey noise (or similar) to drown out the unwanted outside noise. Most systems use a combination of both, as passive noise cancelling is far easier. This is also why you sometimes hear a soft hiss when you activate ANC.
@@lbgstzockt8493 passive noise cancelling is basically what earplugs do, no noise is used.
Very simply, when one speaker is out of phase (wired backwards) in a stereo system, they cancel each other out. Mainly heard in the lower frequencies, but also affecting image and sound staging.
It's heard in all frequencies that are pannes with an identical signal to both speakers. It's the same as a common mode interference supressor in a balanced signal chain. There is usually just one bass and bass drums are usually not panned so that is why they dissapear more than other instruments, has nothing to do with them being low frequency though.
I once played at a psytrance party where one of two subs was wired incorrectly, resulting in the bass literally disappearing right in the middle of the dance floor. 😂 Since is was open air, you hadn't even echoes from walls. Super weird.
@@NeovanGoth The person that made those speaker cables really messed up. Should never happen in a PA system since the speaker cabler are hard wired unless there is a phaze switch somewhere in the system.
I heard about phase back in the 70's. I don't recall being able to hear a difference, but I didn't have speakers that reproduced heavy bass. I've always tried to wire correctly anyway.
Is this how noise cancelling headphones work? They layer on top of your audio an inverted waveform of whatever ambient sound you're hearing?
In a world of misinformation, particularly on audio, this channel is such a breath of fresh air! Superbly explained too.
The "audiophiles" as they call themselves are also incredibly toxic. Ask any questions and you'll get smugly talked down to for not knowing. Disagree with them and you'll get the most vile insults. Stay far away from them.
@@PunakiviAddikti Not only will you get ridiculed for not knowing, but you'll be buried under a mountain of wildly inaccurate or downright wrong information right after.
An excellent, illustrated, detailed, demonstration of speaker polarity, an important factor one that I have been promoting for over 50 years!
Fun fact: I once installed a dual subwoofer setup in my Nissan 100NX (yes it's been a while) .. After installation I played some subwoofer test music and was disapointed by the lack of bass from the subwoofers. I didn't understand, I had two subwoofers and still heard almost nothing. It was at this point I thought about polarity and I changed the phase setting (on one of the amplifiers). It was at this moment I learned that I should not have done that while the system was running a subwoofer bass test on 80% volume. The moment I flipped that switch I was scared to death, the system was playing so load suddenly. Learned some lessons that day!
My college roommate blew out his rear glass because he was trying a test and realized a wire came loose or something. Suddenly bbbrrrrrrrtttttt and he was covered in little glass cubes.
Both subwoofer were trading the airflow they were producing.
After I saw a friend of mine fry his car amp doing what you did, I always turn off the power before switching wires around.
I had an NX2000.
Out of principal you should only do wiring with everything turned on 😂....we did that with our cncs also😮
If you have two stereo speakers wired with opposite polarity (a.k.a half a cycle out of phase), you get an interesting effect because the signals cancel each other out in a fringe pattern which generally makes it feel like the sound is coming from around or behind you, because it will bounce off the room walls before it reaches your ears. This effect is used in legend of zelda ocarina of time for the sound of the townspeople in the castle town courtyard, and in the movie twelve monkeys for the mystery voice he hears in his head
Flipping the polarity of one of the channels in a pop song can also work as a useful hack to get something approximating an instrumental version of the track, because generally the vocal is dead centre but the backing is not so the vocal gets cancelled out
my science teacher did this in school with speakers out of phase and made us walk around the room, the volume changed depending on where you were in the room because of the phase cancellation
But that messes with the "dubbing"
The effect is still in play when recorded, and requires micro editing in the DAW where cancelations occur in track adding...
Someone once suggested changing the waveform, but it's still the inverse frequency loss to deal with.
I seem to recall an old CD player stereo my sister got for Christmas had this as a feature?
(I think it was intended as a Karaoke mode?) I don't remember much other then it was weird to child me for the vocals to just all the sudden disappear like the vocals were on some different audio channel getting disabled.
If you mess with polarities you'll destroy low freqs and some mids as well
Zackley
i was taught this about 30yrs ago from some sound engineers for both studio and live situations. there's also been several articles in guitar magazine about this because especially important to the life of your gear and what's going to go on record. the last interview i read about this was from one of the sound engineers who worked on crew for Jimmy Hendrix on tour. it is as follows:
when you wires your speakers backwards your cones hit in reverse. the initial blast from the speaker, i.e. that first vibration should always be the cone pushing outwards to deliver that first hit.
when you wire them backwards the cones take a breath instead. i.e. pull in instead of pushing forward. that's going to affect the sound quality and volume of your session and speakers.
if you got several amps going and one is in reverse, your phase is going to be messed up. it won't be something crazy like a full cancellation but your signals won't be balanced.
over time, if the speakers are wired in reverse, the initial hit from your speakers will lead to damage from always sucking in at first instead of blowing outwards.
That last bit is wrong. The coil and therefore cone excursion is held in an equilibrium and the availability of excursions in and out are the same therefore there is not any damage to the speaker that sucks in first. It does that hundreds or thousands of times, a second anyway.
They start speaking Spanish
ñ
Yes
You should take a pair of those linear transducers and have them agitate a shallow pool of ~dyed water. In theory, we should be able to see how the delay required to propagate the signals through the media affect constructive and destructive interference at different frequencies, distances, polarities, etc.
Cool idea!
I used the "Chaldini" plates with small metal slivers and video taped them in the 80's. I recall Velvet Underground being quite interesting.
Installing a stroboscope illuminating the water at the same frequency as the waves, will also make it so that the waves appear stationary, so the differences can be pictured better
@@rojirrim7298 I think showing the agitation of the water would be better. Otherwise, when you have a spot with looks like it hasn't moved is that because it cancels or because it just isn't moving at that point.
Alternatively, the stroboscope slightly off frequency, so you can see the waves moving and interacting.
huh huh....you said words.
On a side note, the term phase and polarity are often used to describe the same thing but are actually different.
Polarity inversion (flip or swap)is what is described in this video and is a 180 degree phase inversion.
It is possible to have phase discrepancies that are not a full 180 degrees.
Also, polarity is a reversal of a physical or electrical connection that results in a 180° phase shift.
Many issues can create phase shift. Polarity reversal is just one that has a singular shift.
you must be fun at parties.
You can but they will be different at all frequencies. Simply having one speaker further away from your ears than another will give you a phase change - could be partial or the full 180 depending on frequency.
Yes but phase shift varies with frequency, so you cannot simply apply it to music as a way to counteract poorly-wired speakers.
exactly
WAOW...
the quality of your content is impressive 😄
So sharp and clear, I love it !
Very professional as a teacher for the audience. Great speaker-tone, good info. You have a gift to teach
It's actually fun to experiment with out of phase speakers and placement. If they are directly facing each other with the listener in between, you get a push-pull effect that's pretty cool. It depends on the spacing and frequencies as well.
I hate that effect. Gives me a weird feeling in my ears.
Deafening silence
@@jnawk83 You do not get silence, only damped bass and the higher frequencies is pretty much unaffected but with weird / cool sound effects of "sound phasing".
It can result in a kind of "fake stereo" effect. When I was a kid I got a kick out of doing that. Even better was setting up an AM radio and FM radio on the same station (here in NZ at the time we had stations that broadcasted on both) for whatever reason there was a significant time difference between the two, causing a fairly extreme slapback echo effect. It was a trip.
This is the best audio engineering channel on TH-cam.
Facts
Anyways, thanks for the suggestion!@@corporealundead
Thanks for the information. My brother does musical performance on stage. But most of the time he is dependent on the audio contractors for the sound equipment. Sometimes he used to tell me about some bad performance. At that time I used to explain to him the things you explained. Although I am not a professional like you, as a DIY person and more into Engineering, I used to explain my brother to check out on the speakers, their connection and placings to overcome some problems.(I am now sharing this video with him❤).
Thanks.
Thanx for the thorough explanation of speaker function, especially w/ the visuals of the oscilloscope.
I was becoming doubtful that you were going to explain the effect of swapping polarity of one side of a stereo speaker arrangement, and I was ready to comment w/ the question "What if...?", when you resolved the question w/ an answer. I was also pleased to learn that I was correct in my assumption of a "cancellation" effect.
Using a pair of Sansui SPA-3700s here... that I bought new in 1981... they are properly wired.
Thanks again.
Back in the mid 1970's I worked installing PA systems in a grocery store chain, the system was a 70 volt system that was used to play mono background music when it was not being use for announcements. The speakers were mounted in the ceiling of the stores and to keep the speakers from canceling one another out we had to space the speaker properly to take in account the delay of the audio from each of the speakers and we had to switch the polarity of each of the speakers because of that delay to keep them in phase with one another. This was to minimize the locations in the shopping aisle that presented cancellation zones. It worked very good.
Fascinating. I worked on that stuff too.
Although music is all different frequencies, so there's no one distinct phase change, so may as well just keep all the speakers in phase imo.
Yes. But you guys make me think about something here but not here. We don't have it.
Let me imagine this for a moment or so .. Can't we have a button on our so, advanced remote that we can flip polarity around?
You have to do the math between the ohms of the speakers and series and parallel loads on the amp. You just can't hook them all up in parallel like most people would. Thankfully those days of problems are loin behind me. Uh I meant long behind me. Same thing I guess, oh well.
@@TimpBizkit You are correct that music is all different frequencies, but when you reverse the polarity of one speaker you are reversing or changing the phase of all of the frequencies to that speaker in relation to the other speakers by 180 degrees, so *_PHASE MATTERS._*
Coincidentally last week I was installing an home theater in my room (the old style one, not a sound bar) and I was wondering why the speakers had polarity and I was very afraid of inverting wires. Now everything is very clear. Thanks for the video!
Wow, what a fantastic explanation of sound design, and physics- instant sub! Best Audio channel of the month for 05/24! Congrats
Very very informative, simplified to an understandable way without sounding condescending. Great video❤
Right foot first or left it doesn't matter unless you want to coordinate with another. Just like dancing.
Until you step on your partner's foot.
@@codahighlandThat would impede the good ol' rhythm, no?
Dancing is sinful.
@@BeforeAndAfterScienceI guess Psalm 149:3 is sinful then... maybe the Bible is sinful. Maybe God is sinful. Maybe God is Satan...and Satan is God.
@@BeforeAndAfterScienceNo Scientist makes such an open ended statement without qualifying the parameters thereof.
I don’t think it was mentioned in the video, so I just wanted to add that the common naming when speakers are wired the same is “in phase” and when they are wired with different polarities is “out of phase”. There are some interesting acoustic characteristics when speakers are wired out of phase in a home listening environment where the sound seems to appear diffuse and almost like it’s “floating around your head” with no distinct source. There are some fun examples elsewhere on TH-cam where you can listen to in-phase and out-of-phase white noise that demonstrate this.
What you describe results because vocals and other instruments that are intended to be front and center experience more interference than those panned more to one side or another because they are essentially equal in each speaker. This causes more cancellation of anything in the center.
Im not 100% sure I am correct, but i heard somewhere over the years that some high end speaker manufacturers using a lot of X-over points design speaker cabs with the low bass drivers intentionaly wired 180 degrees out of phase to take advantage of this phenomenon and give the low end a wider sound stage
@@Angel-fq7ww Interesting idea, however, I wonder about this. Bass frequencies are extremely problematic when out of phase between multiple speakers. I would expect dissonant artifacts that would be anything but audiophile, from such a setup.
I don't know the specific acoustic properties, but in the concert PA world, it's fairly common now to physically reverse several of the subwoofer boxes, but not to create phase artifacts. It's done to acoustically cancel bass frequencies behind the subwoofes. It's the speaker equivalent to phase ports on the back of directional microphone capsules. The steers the bass towards the audience and away from the stage where it can be problematic vibrating the performers, their gear, and the microphones on amplifiers and other instruments.
Thank you, the explanation was on key! 🙌🏼
Wow your explanation was beautifully presented and easy to understand!!!! THANK YOU GREAT JOB
It's possible to isolate the voice in all songs that have a similar instrumental version by inverting one of the two audio files. It doesn't work perfectly because of audio compression and sometimes the original song includes more or less sounds than the instrumental. But with a bit of luck you can get pretty good results.
Playing the difference between channels (left minus right) usually cancels out the lead vocal and the bass because the lead vocal and bass are usually mixed dead-center. You get some of the instruments and some of the harmony vocals. It can be mildly amazing. Try it on Olivia Newton-John tunes (she's almost a choir). "Saturday in the Park" by Chicago some surprises that cancellation brings to the front.
@@qazmatron It all depends on the mixing. Many recordings, to save money or because the engineers have tin ears, record the vocals or guitar solos or bass monaurally, and then pan them to the center of the mix. With a single monaural source it's relatively easy to inject a 180º opposite and thus cancel out the original. With true stereo recordings, not so easy.
@@rcarlberg Just flatten the stereo signal to mono...
@@rcarlberg Just flatten the stereo signal to mono
I noticed a difference in sound decades ago on my Dad's stereo. Maybe it's not noticeable on headphones, but if the speakers are far enough apart, the inverted wiring caused it to sound very hollow.
Well explained! It's about adding waves. Thanks!
Extremely clear and methodical explanation. Well done.
I saw a perfect example of this in application - there’s a documentary on making of Metallica’s Black Album where the sound engineers had James Hetfield sing in a booth with two monitors wired in opposite phase so that the mic would only pick up his voice. He was having trouble wearing headphones for some reason. It was truly mind blowing how this worked.
I've felt headphones change my head shape, and damage hair follicles. I'm going to have to play with this, someday.
Actually if you wire your headphones backwards and out of phase with the earth's magnetic field, it causes and aluminum foil hat to grow right out of your head between the hairs, this is fed from the years and years of using underarm deodorants and taking excessive jabs (those "j's" especially as hey go right to the brain which is in close proximity) to the "hat" growing area! Napoleon Hill was experimenting with this, you can tell from his pictures, even tho b&w.... you can see the tell tale peak starting to grow - this is probably WHY his book *"Stink and Grow Rich" was transcribed to cassettes later on :P (*Written after "Think" due to people who avoided the deodorants to stop "hat growth")
Called "balancing phase-shifts"
Many, many years ago (like 1970s), I installed 2 speakers in my car's front doors for my Pioneer Super Tuner stereo system. Somewhere, I saw an article about adding a 3rd speaker and mounting it on the rear deck of the car. I took a positive lead from the left and right channels and connected them to the 3rd speaker. Whether or not or was good for the electronics, I don't know, but it made for an interesting effect since the only sound coming from the 3rd speaker was the difference between the 2 channels. Like sounds were filtered out.
would this still work or would it be obsolete with newer technology?, im sure i can look this up but i want your opinion and im a little lazy
@@dom_xi-dzopa720 I think it would still work. The signal going to the speakers is analog.
It works... Poor man's surround sound...
this was pseudo quadrophonic sound system developed by a bloke called Hafler. i have had my stereo setup like this using 2 speakers for the rear wired in series but opposite polarity since the seventy's.
What a flashback! I had a 1970 Mustang Mach 1 with a Pioneer Supertuner hooked up to a Pioneer 100W amp. 2 bookshelf speakers with 8 in woofers seatbelted in the back seat, each with about 30 feet of wire. When we were hanging out at the park, speakers spread apart and awesome tunes!
Such good explanation and demonstration 👏🏼
This is one of the most well explained and presented videos I've ever seen. Respect 🤜🤛
I've said it before but I'll say it again: you are an incredible teacher!
Thank you!
I'm Subbed now. You bring back old memories.@@AudioUniversity
Years ago when speakers didn't give polarity we used to put them face to face about a half inch apart and reverse the wires on one. Which ever way sounded better is the way you would leave it. We called it putting them in the same phase.
I knew this, but kept watching because the explanation and teaching is flawless! 👌
I appreciate that!
Really interesting to see how little most people (including myself) actually know about these simple concepts. I was taught I could blow up or short circuit speakers when I connected them wrongly
Man spent 7 minutes explaining ANC
This is true that there should be no audible difference when your DAC, amp, and speaker are all operating linearly. However, in practice there are nonlinearities and biases in all these systems. I would imagine it would be easier to A/B test polarity inversion on cheaper systems or at very high sound pressure levels.
This is a fantastic explanation. Great job!
Thank you very much for taking the time making this video….it is appreciated
There is one case in which connecting stereo speakers in reverse polarity is a GOOD thing.
The best imaging and sound stage is acquired by placing a twin set of tweeters and midrange drivers on the outside of your main speakers and wiring them to the opposite channel in reverse polarity to cancel crosstalk. That's how the Polk Audio SDA's work.
I found your comment after I posted mine.
A little known thing about 2-channel automotive amplifiers that are bridgeable: One channel has it's terminals labeled backwards from what it really is. That channel also has it's RCA input reversed. The input signal is being sent into the amp out of phase, but since you are actually wiring that channel backwards, it all comes out correctly and in phase. This is done to make bridging the amp easier.
What does bridging an amp do??
More than you wouldn't believe I was getting ready to throw him away when I realized I had a branched it which I branched it correctly I was shocked at its performance
@fastone371 Bridging just takes 2 channels and combines them to create a single channel with double the power. So 100x2 becomes 200x1, only a bridged amp treats whatever load (8-Ohms, 4-Ohms, etc.) as half the resistance, so a good amplifier delivers twice the power. So that 200x1 can become 400x1. Power is determined by the load. When you halve the load, you double the power, but only if the amp is designed for it.
The old school Orion HCCA amps that were 25x2 @ 4 Ohms were 100x1 @ 4, 200x1 @ 2, or 400x1 @ 1 Ohm.
Wow, awesome video! I have always wondered what would happen and noticed no diference... great explanation man! Thanks
As a kid, audio and speakers were my main interest and I bloody loved experimenting with differing set-ups. Great little video, fella.
Listen to the stereo copy of the debut album by Moby grape. The producer, David Rubinson, put a lot of the backing vocals (and sometimes the main vocals) out if phase; left channel vocals were positive red and right channel was negative red. If you play the stereo copy on a mono player which were prevalent in 1967, the backing vocals and sometimes lead vocals disappear. The producer also did this on a few songs on their second album called ‘Wow’.
I noticed this on at least one of their songs about this. The vocals were very low.
Actually, engineer here, speaker does not have positive and negative terminals. As you said it is just a coil, which is an inductor wound to a circle. Some electronic components and machines does have polarity because it is important where does the current flow and in which direction. That is why you must put DC voltage in correct polarity on input. But as you connect coil to an AC power source you can imagine it not just changing the ammount of current/voltage but also its polarity (sine wave). That means it does not matter which way you plug it in. What were you talking about in video (the speaker muting while "reversed") is phase shift. You phase shifted the signal on one speaker so when the signal on number one is in top + section, the signal on second one is in top - section and then they indeed disturb each other.
So what your saying is if I know which way to wire it before hand like if I mark one red and one black and call it forward for up and reverse for down then we will know hownto connected the speaker just in case they make a mistake like in the factory and forget that hey don't wire that speaker backwards because the customer won't know the difference but don't tell them it's a dc speaker. Sounds good 👍 where did you go to school?
Thank you for this technical info. Appreciate it.
Perfect explanation in a nice calm way.
Thank you.
For me it means, that a pos. Amplitude is pressure carried from the speaker through the air to the ear.
A negative amplitude is vacuum pulled through the air from the ear.
Will this make a difference to the ear?
i "hear" the difference in the snare, but honestly i think it's more about feeling it. the pressure difference in a speaker pushing the note vs pulling the note into existence. sound waves are just a transfer of energy from one object to your eardrum. under normal conditions, the eardrum is pushed first, then pulled by the sound made by the speaker, where as with inverted phase the eardrum is being pulled first, then pushed by the soundwave produced by the speaker, and i think that subtle difference is what people are noticing.
Kind of like the same effect as a fan - there's strong directed flow out of the front, but no strong directed flow into the back?
A snare is usually tuned to ~ 170 hz so that initial "pull" is only 0.0029 seconds (2.9 milliseconds) long before there is a "push" and the cycle repeats.
I'm fairly sure you hear placebo. It makes no difference to a speaker whether it starts the waveform this or that way.
@@hughobyrne2588 No, a fan does not produce a waveform (unless you have a rotary subwoofer). A speaker does not blow air like a fan. The only time you feel air move is when you have a vented sub where air starts to move relatively fast or a horn speaker playing bass at loud volume. But since sound is a waveform, there is no front or back per se, it varies like AC varies in electric grid. Doesn't matter which way you put the plug in.
@@Munakas-wq3gp that is true, a speaker doesn't care, but your inner ear does.
2024 and most of us are still listening to mono audio😂
Why though
Use this to your advantage!: Some vocalists, Motown in particular, liked to record the vocals in the control room. By reversing the polarity on one speaker they could stand in the middle and listen through the speakers and record the vocals and get almost (or minimum) track bleed into the vocal mic. Cool...
Hence, a great example of noise cancelation. This was a very well done video, thanks!
they do sound different - but it is very subtle...one sounds 'softer' and the other 'sounds annoying' ever so slightly haha
great educational video on this. phase inversion is great for filtering/accenting or isolating. keep it up!
Agreed, version B irritated me somehow.
@@liberatumplox625 B Is out of phase, very noticeably softer in mono while stereo in that scenario will be unable to give focus in the middle because the 2 speakers are canceling out each other. Some recordings may be done out of phase deliberately for a much softer and less focusing music reproduction.
Cool. thanks for this information. I am not much of an Audio Freak but have had nice stereo amp systems in the past and always wired up the speakers correctly. Never questioned why the Red/Black wiring - just did it. Thanks for the video and wiring explanations.
Take care.
Great explanation and video!
We used a battery to figure out the polarity of the speakers;when trouble shooting a previous installation. A dead give away is solid bass when turned to one channel or the other, but when balanced no bass out of either indicates inverted polarity on one or more speakers depending upon setup. Our shop used to troubleshoot a lot of other shops work. Motor noise used to be a huge issue for some shops.
I am quite familiar with this concept but this video was very well done to explain it to those who are not. Bravo.
This just happened to of popped up on my TH-cam. I spent many years in the automotive stereo industry, starting out very young. I could never hear the difference AS long as everything was wired the same. But wire one speaker wrong in a stereo system and you most assuredly can and will hear it. That was almost 40 years when I started, and nothing much has changed. Very important to get it right and right the first time. Nothing worse than having that person coming back because you got it wrong.
Gracias, ahora entiendo perfectamente, muy buena explicacion
Very enjoyable to watch, thank you for doing this!
Nice concise presentation. Thank you.
I had some fun trying this out once. Playing the same audio on two speakers, but having one inverted. When putting your ear in a place with the same distance to both speakers, it really gets more quiet (still far from 0, but very noticable). But if you move your head so the distance to both speaker is different (by maybe 10 or 20 cm), it get's louder again, because the waves are ever so slightly out of sync and can't cancel each other out as well.
Great demo to understand phase inversion! I imagine if you want to feel the kick drum as quick as possible out of a subwoofer you want the signal to be in it's regular phase, which is after all a natural reproduction of the sound
Interesting! I always suspected this, but thanks for confirming it.
I've been doing sound in many forms professionally for over 40 years. A lot of crazy things can happen with sound. Let me first say that with a really good and highly tuned stereo system you not only get right to left imaging, (like you can here the saxophone mainly coming from the left speaker and the guitar coming from the right) , you can also get front to rear imaging. So if your listening to a well recorded symphony recording, especially with eyes closed, you can hear the violins at the front and kettle drums in the rear. If you wire both speakers backwards (both speakers are - black wire to red terminal and red wire to black terminal), at first listen they will sound normal. But if you listen more closely, you will hear the kettle drums at the front and the violins at the rear.
Back when I was building and tuning subwoofer enclosures, and learned all about proper tuning for clipping avoidance, I accidentally mis-wired the internals of one enclosure. (Lousy blue/blue stripe wiring convention!) Anyway, had it all nicely tuned for max wattage at 60hz and I could hear "bass" but it was like weirdly quiet. No boom. No SPL compression on my chest. Yeah. . .a quick recheck of everything, discovering my mistake, fixing it, and retry almost left my ears bleeding. 😂 First hand experience in cancelling sound waves!
Thanks for the vid too! Excellent scientific description of my "oops!"
That was a terrific explanation!
The best explanation ever!
Great Info ! Although I plugged the speakers all the same way I always wondered about that.
There are times when reversing polarity is a good thing. I have an SQ build in my car right now with a 3 way set up up front and my midrange are reversed polarity compared to my mid bass and tweeters. It helped me achieve a brighter “center stage” .
5:02 I can hear a difference. With the negative first the start of the hit sounds sharper and more pronounced and that's with my TV/computer monitor speaker volume at 19 without hardly any area background noise since it's mostly quiet where I live.
Impressive. Very good explanation!
Great explanation of how speakers work!
Beautifully explained.
*BEAUTIFUL EXPLANATION*
Great explanation thanks
Thank you for this video
I reverse the polarity of tracks i want to stick out like main vocals when mixing. Great video!
Excellent lesson!
The algorithm was strong with this one. Very cool!
The inverse wiring can be tailored to a room. If you hold dinner parties and want background music, but not so that it overcomes conversation, then put your stereo speakers behind the furniture, but wire one backwards. The people seated can hear the music, but the people standing cannot (or significantly reduced). Also, putting a microphone in your car, and playing the inverse wave back over the speakers will soften the road noise. Great video.
very interesting information... thank you!
Whether or not there's an audible difference will depend on the driver and/or enclosure. The signal is identical, but if the driver performs differently when pushing out vs pushing in, for dynamic audio (basically anything except a tone generator) it will color the sound differently. Like the snare hit example, the largest amplitude is in the 1st movement. If the cone is not equally flexible in both directions, and more flexible in the direction of 1st motion, that period will be louder than when the signal changes direction electrically (i.e. moves under the line).
So, if you have good ears, and you have good drivers and enclosures and yet you can hear a difference when reversing the wires that's actually an indication that your drivers or enclosures aren't good as they do not perform equally in both directions of cone movement. With good equipment, good ears will be just as oblivious to this kind of phase change as bad ears.
Really well explained.
Waaaay back in the mid 70s we had a stereo console with turntable that wasn't working. I was 14 and I started messing around with the player and all that. Just tinkering I got my hands on Quadrophenia. I had heard it was supposed to be in quadrophonic. Somehow by playing with the speakers and crappy old equalizer, I managed to isolate the whole drum track to Love Reign O'er Me; albeit, I could still hear echoes of vocals and other instruments. It was so good, that before the final drumming piece, I could hear one of the band members either sniffle or cough. I'll have to try it again with my gold cd I have of that album.
Phase is a weird thing took me years to be able to spot it the low end and mids have a different feel on hi end monitors have seen it be used to great effect to cancel audio and create cardioid sub arrays or clusters. excellent content we need more good engineers in this industry with good core understanding of the equipment they are using and the physics of it and the audio they are producing.
An old trick for interesting "Surround sound" is to connect a third speaker to the positive output of the left and right amplifier outputs and put it behind you... this third speaker only produces the difference signal (out of phase or otherwise), and adds a lot of "depth" to the image produced by the main stereo pair. If you add a speaker-level "L-Pad" in series with the third speaker, you can dial in a lower volume setting.
We used to do this with a single speaker and a modern car stereo rig installed on 60's cars that had a single speaker mounted high up in the middle of the dashboard or back seat cushion, and a pair of door speakers in the front. We would connect the rear speaker to the rear amp outputs and use the front-to-rear fader to control the amount of "surround" output.
The cancelling out of of opposing signals is why XLR cables don't reproduce induced noise, and can therefore use long runs in noisy environments. The signal is sent down two wires, but opposing each other (with a common ground being the third wire). Any signals that are induced become opposing when one of the signals is inverted at the end and cancel out just the noise. (This is a rather simplified explanation just to get the concept across) 🙂
Finally I Understood How ANC Works !! Nice Video Bro..
I actually have reversed the polarity of my high end speakers, because i noticed a phase issue with my active subwoofer's internal crossover even if i use the preset that was made for the exact speakers i have. Not sure if this is caused by using balanced to a power amp for my speakers and rca for subwoofer, or if it's just my room being weird. but i've never had any issue this way. Glad I don't have to worry about this
Just stumbled across this video. I've always heard about this and always made sure to wire correctly, but now I feel like I need to experiment and actually listen to this cancelling effect.
Nice explanation. Thanks. Your inner ears pretty much do a Fourier transform on what you hear, and only (at least for most of us...) use the magnitude information, so polarity doesn't matter much. Until you start dealing with multiple sound sources, where cancellation becomes important.