Absolute Polarity - Myth or "Important"?

[Thomas_A]

My thought was that most people can hear it after some training. If not what are the reasons for its audibility? Ear physics or processing in the brain?

 

[solderdude]

As long as you don't hear it don't try to hear it ?
Besides for a lot of people the differences, even when audible, do not 'degrade' or alter the music itself in any way and o not really care about a specific aspect.

 

[markus]

Here is another file I tested. Bass from an Alison Kraus record.
View attachment 208993

The waveform:
View attachment 208995

Is there a hard cut at the beginning (and ending) of each sample or did you use a small fade in? Hard cuts often produce audible artefacts, i.e. you might be hearing the edit not the polarity inversion.

 

[Thomas_A]

”Is there a hard cut at the beginning (and ending) of each sample or did you use a small fade in? Hard cuts often produce audible artefacts, i.e. you might be hearing the edit not the polarity inversion.”

I would say this would not affect. I get the same results with Solderdudes Alison Kraus file. The audible difference is in the timbre.

 

[Thomas_A]

While on it, how do you find the short piece of Yoshikazu Mera? Can you play it loud on your speakers and still feel it is pleasant to your ears? It is one of my killer tracks when evaluating speakers.

 

[600_OHM]

Hmm.. couldn't find any audible differences in those test tracks either, but thanks for doing that.

I'm going to have to test some more on percussion, where perhaps I'm losing my touch for detection. This thread has surely been enjoyable.

One thing for sure, my joking research on triangle-solos actually turned up some great info about how to play them properly and even includes FR charts! I truly had no idea there was a lot going on!

Once I get done listening to MB's "In Search Of The Lost Chord", I'm going to go back to see if I can do a test setup like solderdude mentions, and go in search of the lost pecussion strike and document it.

 

[DimitryZ]

Well, thanks to @solderdude , I have a handy AB switch at my listening chair to flip phase at the preamp/amp interface.

And on most modern music it doesn't make a noticeable difference. I suspect modern recordings have many tracks in both normal and reverse phase due to many, many processing steps.

On old recordings (in my case, jazz from 1950-1960s) there is often a difference, but again not a consistent one. Vocals sound better with one phase, base sounds better with another. For music you really enjoy, listening twice is wonderful.

So a fabulous tool to have at your disposal... sometimes. It seems that in balanced equipment, where both phases are available, we should have this feature built in.

If you ask nicely and pay the modest price, he may make one for you. Nice looking, too.

 

[Wolf]

12dB slopes mean phase/polarity reversal, not so with typical 4th order acoustic slopes.

And yes, 1.5vdc is fine on a tweeter for a polarity test. It's also easier if you don't have access to a scope.

I want to add to NOT do this on a ribbon, as it will stretch out the membrane and require a replacement.

 

[Dustyc]

My integrated amp has a reversal switch on the remote. Seems like most simple miked recordings I can hear a difference but anything from the past 15 years it's a toss up . I usually listen for a change in the bass line. Nice feature to have though, and in the digital realm should be easy to do?

 

[Flaesh]

Bob Katz's popular track "Discovery.." with an undoubted absolute polarity:

 

[krabapple]

waveform of the final product doesn't prove that polarity never changed in the production chain.

 

[Flaesh]

waveform of the final product doesn't prove that polarity never changed in the production chain.

Of course. Can we hear it?))..

 

[ctrl]

waveform of the final product doesn't prove that polarity never changed in the production chain.

That there is a difference is not hard to hear with headphones. Which version is the one with inverse polarity might be more difficult.
I think an experienced audio engineer might be able to recognize the original with the correct polarity, at least for certain instruments.

Who wants to test it, here is a post with the link to the Audiocheck website and two test files to download for a blind test in foobar or similar.

 

[krabapple]

Of course. Can we hear it?))..

According to the best science we have the answer is: only under certain conditions.

aka, 'sometimes'

 

[Flaesh]

under certain conditions

Potentially multiple polarity changes in the production chain?))

 

[Holmz]

I

Potentially multiple polarity changes in the production chain?))

Hopefully the multiple is a module 2 = 0 one.

 

[René - Acculution.com]

I think that it should also be discussed that the shown music signals are not what come out of the loudspeakers, and so it becomes real squirly to discuss absolute polarity unless under some controlled conditions. I will not make a long post, as I have already made a long video about my take on loudspeaker phase, polarity, and similar topics.

 

[Thomas_A]

IMO, the "sensitive" frequency region for polarity switch is from 100 Hz up to about 800-1000 Hz. Of course speakers can mess upp this region with crossovers, but using speakers where crossovers are outside that region, there will be audible differences also using speakers for these asymmetric music signals, when flipped.