Does Phase Distortion/Shift Matter in Audio? (no*)

A look at audibility of phase shift/distortion in audio and its practical implication with headphone and speaker listening. Research studies are shown as well as measurements to show the impact of phase deviations.

Dr. Floyd Toole's Book: Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms

On the Audibility of Midrange Phase Distortion in Audio Systems:

[Canadian_Eh_I]

Clearly Paul must clarify his statements, if nothing else, to save phase

[thisisnev]

All the best snake oil takes a scientific fact as its basis and projects it into the realm of fantasy. Paul's fan club consists largely of the people who spent their science classes staring out of the window. I wouldn't mind if they were the only ones falling for it, but too many of them take his words as gospel and spread the myths and legends to newbies across the internet. Thank you, Amir, for standing up for science and truth!

[MrCarlsonsLab]

Nicely explained Amir. In the RF world we use delay and reflections to measure wire lengths and impedance discontinuities. I often tell people, a good understanding of RF principals eases the understanding of audio principals.

[MiDnYTe]

Your content really fills an important void in audio education. I applaud you Sir

[heathwirt]

Paul is mostly a salesman that randomly throws around technical terms to add credence to his sales pitch.

[BogdanWeiss]

Paul McGowen - the most confused & least informed CEO of an Audio company - I’m sure some of their products are well engineered ( by other people ) but the avalanche of Bull emanating from Paul is staggering!!!!

[giriprasadkotte]

Paul pretty much never answers any question straightforward

[geoffs]

Paul’s followers need to realise he is a salesman with superficial technical knowledge. I have watched many of his videos where he demonstrates a total misunderstanding of engineering. Take a look at his videos on audio tuned fuses, elevating speaker cables, different speaker cable design for bass v treble, audible effects of speaker cables, audible differences between usb cables, white board drawings of phase shift, explanation of DSD v PCM, , power regenerators etc. etc. It is alarming that so many people are fooled by snake oil, and not just in audio. This indicates a serious inadequacy in the education system. Our kids are not being taught basic science and how to think critically.

[garydaniels]

I enjoy watching Youtube videos about audio, for advice and entertainment. I am also aware that most presenters have an end game which then will biases there opinion. So this usually colors their comments. So that's what I personally value Amir's advice highly, cause for myself I do not believe He has any "end game" except maybe knowledge.

[snowblow]

My phase has shifted.
Actually, PS audio was the worst amp I ever owned. Had a 5v DC leak and no filtering capacitors.

[dave]

Thank you Amir,
I so enjoy listening to the way you explain audio in a technical but understandable way.
I really appreciate your wide knowledge and experience in all things audio. I look forward to your future insights and explanations .

[rusedgin]

When I saw Paul's video I thought to myself, one of those science audio guys is going to rant it... Bingo! Thank you

[steveunderwood]

Pretty much the first thing you learn when studying audio compression is "throw away the phase". It halves the data in a single move. If phase had any significant effect on human perception of audio, well compressed music would not be so very hard to tell from the original. That said, a blanket statement that phase doesn't matter is misleading. At higher frequencies it certainly doesn't matter, but at bass frequencies, where the wavelength is long, it often can.

[zyghom]

I don't know much about audio and there was a time I watched Paul's videos. Then, one time he touched the point I know very deeply - since then I deleted his channel from my favourites ;-)
And not only his btw.
But still, he is ... charming ;-)

[grizzly]

Thanks Amir. You and Audioholics saved me from the rabbit hole of cables. The ones I have are fine. The only slightly expensive cables I tried where professional ones. Mogami, Gotham and Canare. If they are used to capture music recording, then they are fit for playback at home. No need for exotic marketed "audiophile" stuff.

[El_Porcho]

This was an interesting video but it's incomplete. What Amir is showing (i.e. when a signal's phase is changed at higher frequency due to effects of a filter) is referred to as group delay. Group delay simply means that not all frequencies within a given bandwidth pass through the filter in the same amount of time. The end result (in this situation) is that you wind up with the low frequencies having little or no phase shift and the high frequencies with substantial phase shift. What are the implications of this? Say you have a musical instrument, such as a guitar, with a lot of harmonics that give it a "fairly wide" bandwidth. If you pass this through a band limited channel (i.e. filter) then you are going to phase shift the upper frequencies of the instrument while leaving the lower frequencies unchanged. This is not a simple situation of applying an equal phase shift to all frequencies within the signal (that would certainly be inaudible I would assume). The question then becomes is group delay audible? I don't know the answer and it may be such a minor effect as to be washed out by the room reflections that Amir addresses. I'm simply pointing out this video is somewhat oversimplified as to the complete picture of what is going on with phase change due to a band limited channel.

[zihotki]

Thanks Amir, as usually great info with proofs and explanations. I'm adding the video to favorites list for future reference

[WeeWeeJumbo]

This is lowkey one of the funniest audio enthusiast channels on YouTube

[glenk]

Another great presentation Amir! You know, it’s interesting. The National Research Council (NRC) in Canada funded a lot of the acoustic research Floyd Toole has done. And a lot of really great products were born in NRC research labs - Energy and PSB were/are beneficiaries of Canadian government funded research. Mr. Toole’s book, Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms is an essential reference for anyone into audio.

[Bob.martens]

Before I encountered ASR, Paul's channel was one of many (GR research anyone?) the YT algorithm pushed on me. How young, ignorant and impressionable I was:)
But Paul never convinced me of anything else than his dubious sales techniques. His explanations are glorified wordsalad.