Dumb question?

[Gaz37]

I moved my speakers a few days ago & just noticed that I reconnected them with polarities reversed (both connected the same way so in phase) & despite swapping them back & forth several times can't be sure I can hear any difference.
Should it make a difference?

 

[Gray]

As you say, you're still in phase. (Just out of phase with (most) of the rest of the world)

Golden ears might detect leading edges of notes sucking instead of blowing!? Now there's a setup for some jokes.

 

[CnoEvil]

Bass definition and depth should suffer, as well as imaging and a treble that loses focus....but bass is the biggest problem.

 

[Gaz37]

Getting a comparison having to turn te amp off swap cables turn back on etc.

 

[Oldphrt]

Bass definition and depth should suffer, as well as imaging and a treble that loses focus....but bass is the biggest problem.

Not if the phase remained correct, which it was.

 

[CnoEvil]

Bass definition and depth should suffer, as well as imaging and a treble that loses focus....but bass is the biggest problem.

Not if the phase remained correct, which it was.

Surely, if the Bass drivers are moving "In", when they should be moving "Out", they won't be able to shift the amount of air needed to give decent bass?

 

[Oldphrt]

Bass definition and depth should suffer, as well as imaging and a treble that loses focus....but bass is the biggest problem.

Not if the phase remained correct, which it was.

Surely, if the Bass drivers are moving "In", when they should be moving "Out", they won't be able to shift the amount of air needed to give decent bass?

A bass note is a waveform that causes the cone to move in and out, so it doesn't matter.

 

[CnoEvil]

A bass note is a waveform that causes the cone to move in and out, so it doesn't matter.

Maybe so, but reversing the Polarity, is flipping the waveform around its axis, giving a mirror image of what you should have...so if a Drum gets its bass definition by the outwards movement of the cone, it will now be weakened by an inwards movement.

It might not be as dramatic as the cancelling effect of having the speakers out of phase, but it will mess with what you hear.

Anyway, that's my understanding.

 

[Electro]

My old Rel subwoofer( very old long gone ) had a phase reversal button *smile* .

Some amplifiers are built with the ouputs phase inverted .

Here is a good article on the subject.

https://www.stereophile.com/content/absolute-phase-fact-or-fallacy

 

[CnoEvil]

My old Rel subwoofer( very old long gone ) had a phase reversal button *smile* .

Some amplifiers are built with the ouputs phase inverted .

Here is a good article on the subject.

https://www.stereophile.com/content/absolute-phase-fact-or-fallacy

Thx, that is interesting....and to some degree, along with a bit of Googling, shows that messing about with Polarity gives inconsistent results.

 

[Oldphrt]

A bass note is a waveform that causes the cone to move in and out, so it doesn't matter.

Maybe so, but reversing the Polarity, is flipping the waveform around its axis, giving a mirror image of what you should have...so if a Drum gets its bass definition by the outwards movement of the cone, it will now be weakened by an inwards movement.

It might not be as dramatic as the cancelling effect of having the speakers out of phase, but it will mess with what you hear.

Anyway, that's my understanding.

If it was a problem amplifiers would have to have a phase reversal switch, because there's no way of knowing if the phase got flipped during the recording of your music or one of your sources flipped it. I would suggest that you don't worry about it.

 

[CnoEvil]

I would suggest that you don't worry about it.

I'm not really...just trying to understand it a bit.

 

[lindsayt]

Do unamplified bass drums sound different if your sitting behind the drummer or in front? Or even if you're sitting to the side?

I can't tell any difference apart from what would be explained by the acoustics of the different positions in the room.

Behind the drummer equals the initial transient rise being that of sucking the air away from you. Still sounds like a bass drum.

 

[MajorFubar]

I'm not really...just trying to understand it a bit.

Fair enough. Signals are made up of equal +/- movements about a zero point, which is why you can cancel a signal out by reversing its phase and overlapping it with the original. There is absolutely no difference whatsoever when you wire both speakers the opposite way, though I can appreciate why you might think there could be. In any case there's no way you could ever know which way the drivers are wired.

Hope that helps 🙂

 

[lindsayt]

I'm not really...just trying to understand it a bit.

...In any case there's no way you could ever know which way the drivers are wired.

Hope that helps 🙂

For tweeters that's true.

For bass units you could apply a small amount of DC, eg from a small battery to see which way the drivers moved.

 

[newlash09]

I'm not really...just trying to understand it a bit.

 ...In any case there's no way you could ever know which way the drivers are wired.

Hope that helps 🙂

For tweeters that's true.

For bass units you could apply a small amount of DC, eg from a small battery to see which way the drivers moved.

And mid range drivers too, works very well to identify matching polarities on the drivers

 

[CnoEvil]

Fair enough. Signals are made up of equal +/- movements about a zero point, which is why you can cancel a signal out by reversing its phase and overlapping it with the original. There is absolutely no difference whatsoever when you wire both speakers the opposite way, though I can appreciate why you might think there could be. In any case there's no way you could ever know which way the drivers are wired.

Hope that helps 🙂

Thx Major.

It's not something I'm going to test for myself - so until I hear different, that seems reasonable...and certainly seems to be where the balance of opinion is.

 

[Gaz37]

So it seems my own experience is in line with the reaearch in the link posted.
I felt it should make a difference but really couldn't decide if it did or not.
I assume therefore that any difference there may be is so minor as to not be worth worrying about?
Slightly annoying as when "installing" my speaker cable (which is plain white with an almost undetectable ridge) I used a 9v battery & multimeter to get the polarity coŕrect

 

[davedotco]

With normal recordings, absolute phase will have no audible effect on recorded music. It is just possible, I have heard claims to that effect, that with a recording of a single instrument or voice some people can 'hear' absolute phase. Can't hear it myself though.

The real fun occurs in regular recording practice. Professional recording microphone generate a balanced output by design, but given the perversity of the world of pro audio, europe and the USA use different standards on the 'standard' XLR connector. In europe pin 2 is +ve, pin 3 -ve, in the USA it is the other way round.

So if you use a mix of mics from different manufacturers, say, Shure, Electrovoice etc from the USA, AKG, Sennheisser etc from europe, they will be out of phase with each other. Back in the day, EMI technical department in Hayes would test and if necessary, reverse phase of mics bought for their studios, on the other hand, I know of many studios who were not even aware of the issue!

I would expect many regular commercial recordings will 'feature' out of phase mics, some are well known, others simply unnoticed.

 

[Gray]

With normal recordings, absolute phase will have no audible effect on recorded music. It is just possible, I have heard claims to that effect, that with a recording of a single instrument or voice some people can 'hear' absolute phase. Can't hear it myself though.

The real fun occurs in regular recording practice. Professional recording microphone generate a balanced output by design, but given the perversity of the world of pro audio, europe and the USA use different standards on the 'standard' XLR connector. In europe pin 2 is +ve, pin 3 -ve, in the USA it is the other way round.

So if you use a mix of mics from different manufacturers, say, Shure, Electrovoice etc from the USA, AKG, Sennheisser etc from europe, they will be out of phase with each other. Back in the day, EMI technical department in Hayes would test and if necessary, reverse phase of mics bought for their studios, on the other hand, I know of many studios who were not even aware of the issue!

I would expect many regular commercial recordings will 'feature' out of phase mics, some are well known, others simply unnoticed.

Nothing would surprise me. I noticed a radio station playing with stereo channels reversed once (only because I knew the record well). Unforgiveable.