Can you hear inverted phase

[metaphacts]

No one is denying "a difference", not Lipshitz, Shanefield, anyone. So yes, it is 100% correct to then ask if better/worse/preferred

So the next step is to research/identify what those acknowledged differences are.

It is not to ask which you like or which is better.

 

[AJ Soundfield]

So the next step is to research/identify what those acknowledged differences are.

You may want to check the thread title and subsequent references if not clear.

It is not to ask which you like or which is better.

But it is, otherwise, yet another audiophile tempest in a teapot

 

[metaphacts]

You may want to check the thread title and subsequent references if not clear.
But it is, otherwise, yet another audiophile tempest in a teapot

Thread title is clear. References are misleading at best, sloppy science at worst.

Not sure what this manufactured tempest actually is.

Absolute polarity/inversion is free.

If you find/believe it matters, you use it.

If not, you don't.

Pretty simple actually


And on that note, I'm checking temp on the tri-tip on the grill. Hmm, wonder if I should invert it before pulling it.

 

[AJ Soundfield]

A product manager thought he could not hear phase inversion. Yet when I played some bass-heavy music (e.g. Billie Jean from Thriller SACD, if I remember correctly), he was surprised that he could actually hear it, and the drum sounded so different in our Vivid Giya G2 setup.

Back to our tests. In the particular tracks we tried, we came to a conclusion that a correct phase gives more audible details. Yet there were also cases where some people (subjectively) like the incorrect phase more for particular tracks. (This may also be an example of that the most accurate audio presentation is not necessarily the most enjoyable for a listener's subjective taste.)

So, do you guys hear phase inversion?

More About Absolute Polarity
Article By Dan Shanefield
From BAS Volume 17 Number 3, November 1989​

He certainly is correct that absolute polarity has sometimes been (barely) audible in double-blind tests.​

But Johnson failed to mention another critical point. The Summary section of the Lipshitz et al report (on page 593) says that the audibility of polarity changes in music played over loudspeakers is only "extremely subtle." This evaluation is confirmed in an exchange of comments between me and Lipshitz et al published in the J.A.E.S. vol. 31 no. 6, in which we all agreed that for music on loudspeakers absolute polarity is (1) not strongly audible to most people, (2) not usually audible above 500Hz (more so below), (3) possibly not as audible over loudspeakers which are comparatively free of asymmetry effects (such as second harmonic distortion). In these letters I said that all kinds of phase effects were "of negligible importance," and Lipshitz et al said at the very end, "We are basically in agreement with Dr. Shanefield."​

Further evidence in support of all this is an article in the Stereophile (vol. 4 no. 8), in which there was no audibility of polarity during blind tests done with the use of low-distortion loudspeakers and yet there was good audibility when cheaper, asymmetrical distortion speakers were used. Stereophile's overall conclusion was that absolute phase is of "virtually no significance."​

​

There is a principle in science which can be stated, "Once you see evidence of an additional factor which might really be causing the observed results, you should never ignore it in further studies. Instead, it must be carefully eliminated." In this case the "possible additional factor" could be asymmetry in the loudspeaker, or it could be delusion on the part of the investigator. Both have been mentioned in studies of this kind, and both must be eliminated in future experimental procedures or else the results might be mistakenly interpreted. The scientific investigator should report what was done about this when giving conclusions—otherwise we should all doubt the results.

​

Actually, I hope several such groups of people will do some foolproof tests and show us that absolute polarity really is important after all. And I hope I'm one of the first people to read about it and adjust my playback system, or practice listening, or whatever I have to do to take advantage of it. Then I can feel superior to the myriad audiophiles who aren't hip.​

But until this happens, we should all conclude that the whole business is a tempest in a teapot.​

Dan Shanefield. (New Jersey)​

I agree to some extent - it seems to be recording (and system set-up) related.

I have NEVER had a client who could not hear the difference and express a correct acoustic polarity preference for the majority of the inverted tracks from my RoomPlay playlist. Of course, those cuts may feature transients such as from pianos, drums (most any drum, but especially rimshots, struck wood blocks, etc.), guitar plucks, upright bass (such as Brian Bromberg's Wood II, not only for the bass note attacks, but also for when he uses the fret board as a percussion instrument).

Vocals are harder to diagnose. First, the system set-up needs to be really dialed in (an exceedingly rare occasion, IME). Correct acoustic polarity seems to give some vocalists a bit more presence, as if they are more forward in the sound stage. It's easier with close mic'd recordings, IMO. With some recordings, I simply cannot be sure of which is better.

Absolute Polarity can be inverted in Roon’s DSP section. Long discussion about it in their community forum. Lots of opinions on whether it’s worth messing with or not.

Thread title is clear. References are misleading at best, sloppy science at worst.

 

[audio.bill]

How does one tell if the phase is inverted, or not? I use balanced connections between all gear, and none have a phase inversion button.

Bud - It can get a bit confusing to explain but since no one else answered you yet I'll give it a try... XLR connectors are most commonly wired with pin 2 hot, but some brands invert the more common polarity and wire pin 2 cold (as also detailed in the OP of this thread.) So if you're connecting any components with inverted polarity via XLR cables you need to consider that each connection between an inverted XLR and non-inverted XLR components will effectively reverse absolute phase. So you have to add up the number of such connections and if there's an odd number your system will end up with inverted absolute phase, but with an even number of such inverted connections you'll end up with the signal being in proper absolute phase. As long as the components you have connected via XLR cables all have common polarity (most likely with pin 2 hot) then your system will maintain proper absolute phase. So to be sure check the manual for each of your XLR connected components to confirm their XLR wiring polarity and go from there. Many listeners cannot hear the difference between proper or inverted absolute phase and it's been estimated that about half of recordings may have inverted absolute phase anyway, so you may consider it to be a moot point. Of course in high end audio everything seems to have some impact so YMMV would apply. If none of your components allow you to invert polarity then there's really no simple way for you to correct it if needed, other than having one pair of XLR cables wired with inverted polarity. Hope this helps and didn't confuse the issue further!

 

[AJ Soundfield]

Better answer is that it's yet another thing to drive audiophiles nuts, if they aren't there already

 

[astrotoy]

Because of an earlier post, we want to make sure people don't confuse inverted phase with out of phase. The latter is when one set of speaker wires is connected the opposite way to the other set of speaker wires (for example, red is connected to the black terminal on only one speaker. The out of phase connection makes the sound fuzzy and out of focus. Everyone should easily hear that.

For inverted phase, think of a trumpet. When the trumpet player blows his horn there is positive air pressure leaving the horn and if your system is in correct phase that positive pressure reaches your ear, pushing on your ear drum. On the other hand, if your system has inverted phase, then the sound is created by negative pressure, pulling on your ear drum. Think blow vs. suck. Both cause a sound. In other contexts there is bj vs. sj, or suck up vs blow up.


Larry

 

[BlueFox]

Bud - It can get a bit confusing to explain but since no one else answered you yet I'll give it a try... XLR connectors are most commonly wired with pin 2 hot, but some brands invert the more common polarity and wire pin 2 cold (as also detailed in the OP of this thread.) So if you're connecting any components with inverted polarity via XLR cables you need to consider that each connection between an inverted XLR and non-inverted XLR components will effectively reverse absolute phase. So you have to add up the number of such connections and if there's an odd number your system will end up with inverted absolute phase, but with an even number of such inverted connections you'll end up with the signal being in proper absolute phase. As long as the components you have connected via XLR cables all have common polarity (most likely with pin 2 hot) then your system will maintain proper absolute phase. So to be sure check the manual for each of your XLR connected components to confirm their XLR wiring polarity and go from there. Many listeners cannot hear the difference between proper or inverted absolute phase and it's been estimated that about half of recordings may have inverted absolute phase anyway, so you may consider it to be a moot point. Of course in high end audio everything seems to have some impact so YMMV would apply. If none of your components allow you to invert polarity then there's really no simple way for you to correct it if needed, other than having one pair of XLR cables wired with inverted polarity. Hope this helps and didn't confuse the issue further!

Thanks. I think.

Since only Pass is in the circuit, it should be the same throughout. Of course, whether it is inverted or not is another question.

 

[wklie]

How does one tell if the phase is inverted, or not? I use balanced connections between all gear, and none have a phase inversion button.

Your Lumin has a Phase Invert feature in Lumin app settings for the player.

Toggle that setting for some bass heavy music and see if you hear any difference.

 

[wklie]

Yep. No "Absolute" conclusions about "better/worse"....just like all controlled tests.

Not disagreeing with you. This is merely FYI. In the test I mentioned, the product manager heard more details from the "correct" phase. It was even a blind test, and he got that 100% right in all trials.

 

[wklie]

Further evidence in support of all this is an article in the Stereophile (vol. 4 no. 8), in which there was no audibility of polarity during blind tests done with the use of low-distortion loudspeakers and yet there was good audibility when cheaper, asymmetrical distortion speakers were used.
​

If this implies our beloved Vivid Giya G2 is cheap, then I must disagree with it.
​

 

[puroagave]

I saw a statistic somewhere that claimed up to 50% of pop music is phase inverted on play back and in multi-track recordings (the vast majority of ALL modern recordings) phase is often inverted on individual tracks. As a matter of course, many (most?) recording studios inadvertently invert phase somewhere in the recording process. In Larry's CJ example its a 'good to have' data point but knowing 50% of what you listen to is outta phase anyways, some music will be 'in phase' 50% of the time, regardless--most listeners are agnostic to this fact. That said, The Wood Effect is a good read and 30 years on its more relevant today in perfectionist audio than ever.

 

[Spock]

I have no definitive opinion about this subject.
Saying better, i think there´s more to discovery about phase than some scientists have reached in the early days of the mysterys of the sound.
And yes, probably we are yet in these early days of discovery. If we think that the universe is made of vibration, and that vibration induces a frequencie, a sound, the first sound, the sound of "God"... If we think about all that we don´t know about magnetic fields, and how they are important to achieve the ultimate excellence in sound reprodution, maybe we have to conclude there´s a long way to run.

I saw a statistic somewhere that claimed up to 50% of pop music is phase inverted on play back and in multi-track recordings (the vast majority of ALL modern recordings) phase is often inverted on individual tracks.

That explain why, some times the record A sounds better than record B, and after some up grade (a cable, a fuse) the record B sounds better than A.
I get confused when, after making a new power cable, the sound gets "right" and i think to myself; What is better? I´m hearing the same instruments, the same detail, but every thing gets more quiet, each instrument is better located and defined in space. What happened? Phase correction?

 

[AJ Soundfield]

If this implies our beloved Vivid Giya G2 is cheap, then I must disagree with it.
​

It means there are factors that can make it more or less audible. Your Giyas aren't cheap.
Your initial question of whether it is or isn't audible has long been established. Whether better/worse/preferred has not. You said so yourself in first post.

Back to our tests. In the particular tracks we tried, we came to a conclusion that a correct phase gives more audible details. Yet there were also cases where some people (subjectively) like the incorrect phase more for particular tracks. (This may also be an example of that the most accurate audio presentation is not necessarily the most enjoyable for a listener's subjective taste.)

The vast majority of stereo recordings are studio constructs of unknown provenance. There is no "absolute phase".
I'm quite familiar with DSP. I can and do linearize phase in my speakers. I'm also not an audiophile, so I do account for self deception/delusion in testing, accounting for such factors by using an ABX box. I'm quite aware of what phase inversion to random recordings as well as specific test material does.
Ironically, the AES meet next weekend will feature..you guessed it, a phase linearized system demo http://www.aes.org/blog/2018/9/live-sound-legend-john-meyer-to-present
Glad you includes a phase switch in your software. Options are good, even for folks with constant unease.

 

[audio.bill]

Because of an earlier post, we want to make sure people don't confuse inverted phase with out of phase. The latter is when one set of speaker wires is connected the opposite way to the other set of speaker wires (for example, red is connected to the black terminal on only one speaker. The out of phase connection makes the sound fuzzy and out of focus. Everyone should easily hear that.

For inverted phase, think of a trumpet. When the trumpet player blows his horn there is positive air pressure leaving the horn and if your system is in correct phase that positive pressure reaches your ear, pushing on your ear drum. On the other hand, if your system has inverted phase, then the sound is created by negative pressure, pulling on your ear drum. Think blow vs. suck. Both cause a sound. In other contexts there is bj vs. sj, or suck up vs blow up.

Larry

Larry - Thanks for your effort to better explain absolute phase. One further clarification I'd like to make is regarding your second paragraph and 'pushing' vs. 'pulling'. Since we're dealing with musical signals which are composed of AC sine waves, the difference is actually only in whether it pushes or pulls on the first half of the sine wave. So for example if an instrument's actual sound is generated as push-pull, if the system has inverted absolute phase it would instead be reproduced as pull-push. So it's not actually as simple as comparing positive pressure vs. negative pressure, but rather only which pressure occurs first in the waveform's cycle.