Polarisation voltage quiz!

[tonzauber]

Two notes here:

1) With microphones and preamps it is about polarity, not phase. (allthough the switch is labeled phase, it just changes the polarity of the signal. inverting phase would be a whole lot different).

2.) without some reference, it is impossible to determin polarity of a signal, because acoustically it just makes no difference as long as you are not summing two similar signals together.

But of course if you have several microphones and some have inversed polairity, you can notice a difference.

I have followed up your cited wikipedia source, and putting it politely, it is all very vague. From my point of view this is more about non-linearities of reproduction systems than the ability of our hearing to perceive absolute phase. (e.g: A speaker reacts slightly differently when the cone is sucked in by the voice coil than when it is pushed away)

 

[ln76d]

Hmm...

Still ayway am going to test my hearing

I always hear when phase or polarity, whatever it's called, is reversed - without any reference source.
I don't even know how to describe that difference is really hard to find proper words

 

[tonzauber]

so you connect one microphone that you have never heared before and can say it is polarity reversed?

 

[ln76d]

When i use "phase" switch for comparison - then i hear when is ok and when is reversed.
When i know microphone type very well, even without it...
This was confirmed also when i repaired wrong wired microphones, whatever it is condenser or dynamic.
Typical for self repairs of SM58 for example, when blue go to the pin2 and red to the pin3 in standard
Usual first i hear the mic, then i open it.
To be honest, i don't know how this work with instruments i didn't tested that.
I always hear that on my voice as a source.
Tomorrow i will do the test with stereo and changing polarity of both speakers

 

[tonzauber]

listening via headphones I assume...

then it is easy:

When the mic signal is polarity inverted, and you listen to it through headphones while talking into it, there will be some cancellation  of the signal your bones transport to your ear and the polarity inversed signal via headphones.

This is a typical problem when assessing microphone capsules in figure of 8: one side will sound "good", the polarity reversed other side will sound "different", when in fact both sides are matched perfectly.

This would also explain why your girlfriend does not hear the difference, assuming it is still you talking into the microphone.

 

[ln76d]

Ok also do tomorrow test with headphones but it can be a little controversial result.
About it tomorrow
Yeap i was the "source".
Ah!

Quote from wiki was as a joke

 

[Khron]

What exactly will those hearing tests involve, i wonder?

Hmm...

Still ayway am going to test my hearing

I always hear when phase or polarity, whatever it's called, is reversed - without any reference source.
I don't even know how to describe that difference is really hard to find proper words

PS: https://youtu.be/BYTlN6wjcvQ?t=2864  :

 

[ln76d]

I don't know how these things are called after all i will write more about it.
I know that one of the test for cochlea damage is listening 1dB difference or somthing like this

 

[Khron]

I kinda had a hunch those tests would only involve amplitude. The "mystery" of audible absolue polarity reversal still stands, then

 

[ln76d]

Not exactly.
Cochlea defects can have different weird symptoms. Of course any hearing tests will not show is it caused by defect but if it's truly something unusual we can assume that it can be related.
Could someone take few different microphones and check polarity switching in mono listening?
Is it truly something unusual?
Am i ******* unicorn or what?
I have two teeth in horisontal but this?
Today i did listening test with headphones but i could only hear on one ear - is it valid for test?
When i get some small console i will test on both ears simultaneously.
Anyway, i hear difference with figure of eight sides and still hear polarity switching.
Later i will play with speakers polarity in stereo listening.

 

[Matt Nolan]

Hearing an out of phase mic with headphones with your voice as the source works well, we all agree.

It would seem possible that someone using speakers in an environment they are used to may be able to learn the sound of in phase and out of phase mics with their voice as the source also.

The other thing to note about capsule polarity is that plosive sound, percussive sound and bowed string instrument sound waveforms are not symmetrical. Class A amplifiers are not symmetrical either (some more so than others, some very linear indeed, but let's roll with this). So, the sound of an asymmetric signal through an asymmetric amplifier can sound subtly different depending on the polarity of the signal coming off the capsule - do the larger peaks of the waveform get compressed more or less?

After multiple class A stages with potentially different polarities, the result could be quite muddied. But just thinking about a capsule and the mic's own head amplifier, loud, asymmetric signals can end up looking quite different in their extremities. This could well be audible.

 

[ln76d]

Ok, so  i have damaged cochlea. I did today tests for quick, need to repeat it different day.
I hear an increase of 1dB, so it isn't anything good even if it seems otherwise.
This may also explain why'm hearing strange details.

 

[Khron]

Well then, i guess it's official - it *IS* all in your head, quite literally ;D

 

[ln76d]

No, it's quite opposite - i hear more than you on several frequencies, where my hearing is more sensitive due to defect
BTW. you are drummer so probably my grandmother have better hearing

 

[Khron]

Hardy-har-har How can you be so sure i'm just as ******** as 98% of the other amateur drummers, and i don't use ear protection?

No, it's quite opposite - i hear more than you on several frequencies, where my hearing is more sensitive due to defect
BTW. you are drummer so probably my grandmother have better hearing

 

[ln76d]

I assume that, since you like the sound of SE 2200
Ok, now seriously
Most of industrial workers also use ear protection, many still have big defects in hearing.
Unfortunately drums, which are really beautiful instrument, are not so far in level from a decent factory...
It's worth to check sometimes your hearing
And btw. if i'll be able to hear not existing things, probably i would have loss in low frequency area

 

[Khron]

How did you figure that one out, too?

Factory workers are exposed to high noise levels 8h/day. I'm most definitely not - i haven't even seen my kit in... 2 weeks, or 3?
And i'm really not a hard-hitter anyway

But yeah, i'll see about that when i visit home for the holidays, at least for curiosity's sake I'm just slightly skeptical about the linearity of the test-headphones, or whether their results compensate for that ;D

 

[ln76d]

Yeap, but the factory noise level is usual more constant, not "explosive", drums are rather like loud impulses.
Other thing is drums alone and other whole band on the gig.
For hearing tests definately go to medical center not to hearing aids shop - it's  big difference.
Good audiologist have proper headphones, that's why they measure only speech frequency range.
Test equipment is also calibrated.
Even if you are sceptical about headphones linearity, usual bone conduction measurement will verify, do you have loss at some frequency.

 

[micaddict]

Yeap, but the factory noise level is usual more constant, not "explosive", drums are rather like loud impulses.

Although I'm not an audiologist, I know this is correct. Our ears actually have a defense mechanism, but it is too slow to protect against loud impulses.