hearing Absolute Phase is irrelevant, if not BS; possible only in case when knowing Origin Phase with no doubt ........ so relevant only in recording process and post/production
hearing Your Preferred Phase is what's real and important
btw. as Pa did show in one/some of his recent articles, flipping speakers phase is also flipping phase of dominant harmonic in THD Spectra
hearing Your Preferred Phase is what's real and important
btw. as Pa did show in one/some of his recent articles, flipping speakers phase is also flipping phase of dominant harmonic in THD Spectra
I believe people can hear if there is transistors in a tube amp. Cheap cables from good ones. DC coupled vs coupling capacitors. Even if you bypassed electrolytics with film caps. But I'll take all comers and even give modest odds that in a fair and properly done Blind AB test that nobody can hear absolute phase listening to music. No offense meant to anyone that thinks they can but I can't even see how it would be possible. I'd love to be educated if I am in error. Always willing to learn something new.
I think the photo's aspect ratio was tweaked a little getting it to fit as well. Or resized in width by the browser. Just wanted to verify the boards were not rev'd and the text not updated.
Just to provide the counterpoint -- I'm sure I can hear a difference, though I am equally sure it has almost nothing to do with matching the sound of that music performed live. It is a very situational thing, and in many systems, maybe most, it isn't audible. The more drivers in a multiway system, the more complex the crossover networks, the more feedback, the lower the audibility.
With full range drivers only, simple amps with little feedback yet relatively low distortion, it can be heard. BUT -- the recording has to be 'good'. If the recording is heavily multi-tracked, or the mic locations imprecise, the audibility suffers. Heavy use of mixing and mastering effects get in the way
Just to muddle the issue a little further, some recordings sound better phased one way, others the opposite. This happens often from one track to the next.
When I set up my system or modify it, I'll check it both ways, initially for sure, and often a few weeks later so I'm hearing a variety of music. Then I leave it alone.
As I've explained, I think it can matter, but it's hardly worth a worry.
Skip
With full range drivers only, simple amps with little feedback yet relatively low distortion, it can be heard. BUT -- the recording has to be 'good'. If the recording is heavily multi-tracked, or the mic locations imprecise, the audibility suffers. Heavy use of mixing and mastering effects get in the way
Just to muddle the issue a little further, some recordings sound better phased one way, others the opposite. This happens often from one track to the next.
When I set up my system or modify it, I'll check it both ways, initially for sure, and often a few weeks later so I'm hearing a variety of music. Then I leave it alone.
As I've explained, I think it can matter, but it's hardly worth a worry.
Skip
As Zen Mod states absolute phase is irrelevant outside of the recording studio. Within, however, there are important considerations. I record my piano with 4 mics either onto tape or digital (=Samplitude). Because of the spatial difference between close and proximity mics, the absolute phase starts to wander. In Samplitude, you can go in and move the entire mic line in small increments left and right -- this brings all back into true absolute phase and makes a marked difference in sound clarity and cohesion. Try it and you'll see the improvement.
But if it doesn't matter outside the studio... aka on playback... why bother?
If you can make a "marked difference in sound clarity and cohesion" in the recording surely that's always evident at home and arguably more evident in a coherent system (full-range loudspeaker systems, etc.
Just sayin'...
@mhenschel states:
"But if it doesn't matter outside the studio... aka on playback... why bother?"
The purpose behind studio correction is to have the product as close to perfect as possible when it leaves the studio. In this regard, phase correction is an essential part of high-quality work. Once it goes into the real world, there is constant degradation -- so starting out with perfection minimizes the eventual loss.
Here's what I have found about phase in my home listening areas.
The strongest amount of phase distortion comes from speaker ports. Since these introduce a delayed signal, 180 degrees out of phase, these ports will cause significant problems with soundstage accuracy and timbral identification. My solution is to kill the port noise as completely as possible with an absorbent noise panel directly behind the port. If you try this you will see how dramatic an improvement this can be.
Secondly, your room will introduce phase distortion from unequal reflections. All rooms have this to some degree and the cure for me is to kill the first reverberation -- directly across from the wall facing the speaker. Again, produces a dramatic improvement.
"But if it doesn't matter outside the studio... aka on playback... why bother?"
The purpose behind studio correction is to have the product as close to perfect as possible when it leaves the studio. In this regard, phase correction is an essential part of high-quality work. Once it goes into the real world, there is constant degradation -- so starting out with perfection minimizes the eventual loss.
Here's what I have found about phase in my home listening areas.
The strongest amount of phase distortion comes from speaker ports. Since these introduce a delayed signal, 180 degrees out of phase, these ports will cause significant problems with soundstage accuracy and timbral identification. My solution is to kill the port noise as completely as possible with an absorbent noise panel directly behind the port. If you try this you will see how dramatic an improvement this can be.
Secondly, your room will introduce phase distortion from unequal reflections. All rooms have this to some degree and the cure for me is to kill the first reverberation -- directly across from the wall facing the speaker. Again, produces a dramatic improvement.
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There are 2 articles on the passdiy.com site. I'm not savvy enough to know if they pertain to the phase arguments above. Nor are my ears good enough to tell if there is a difference
The 2nd article says, and I may gave taken the quote out if context
I don't want to muddy the waters with my ignorance. My aim is to point to 2 published sources that may be relevant.
https://www.passdiy.com/project/articles/phase-coherent-crossover-networks
https://www.passdiy.com/project/articles/single-ended-class-a
The 2nd article says, and I may gave taken the quote out if context
I don't want to muddy the waters with my ignorance. My aim is to point to 2 published sources that may be relevant.
https://www.passdiy.com/project/articles/phase-coherent-crossover-networks
https://www.passdiy.com/project/articles/single-ended-class-a
@Craigl59
@jackinnj
Yes the topic is Pearl3 but in the context of upgrading from previous Pearls -- and perhaps other phono stages -- the matter of circuits that invert... and those that don't... is pertinent.
As Craig indicated, better recordings pay attention to phase and those recordings reward the builder/ listener who pays such issues mind too, no?
@jackinnj
Yes the topic is Pearl3 but in the context of upgrading from previous Pearls -- and perhaps other phono stages -- the matter of circuits that invert... and those that don't... is pertinent.
As Craig indicated, better recordings pay attention to phase and those recordings reward the builder/ listener who pays such issues mind too, no?
Pass's brilliant description:
"This means that for a given motion of a diaphragm acting on air, the positive pressure perturbations will be slightly greater than the negative. From this we see that air is phase sensitive."
Applies in the physical world of acoustic energy. Interestingly, this is not the world of DAW. Here, the waveform exists in an immutable form that can be altered in many ways before eventual D/A conversion.
Great articles, @rif.
"This means that for a given motion of a diaphragm acting on air, the positive pressure perturbations will be slightly greater than the negative. From this we see that air is phase sensitive."
Applies in the physical world of acoustic energy. Interestingly, this is not the world of DAW. Here, the waveform exists in an immutable form that can be altered in many ways before eventual D/A conversion.
Great articles, @rif.
It is pertinent... to a point. Beyond that it digresses to the point of cluttering the original thread.
Yes. I think it may be difficult to hear in simple AB comparisons. But, when it is your own system you are very familiar with, there is a difference, which seems to vary a bit among power amps. It's sort of like being at the eye doctor and they are asking, "which is more clear, one or two." "Three, or four." And so on. They come at you every which way with combinations to nail it down, it's a simple A B test, so the additional trouble is taken.
The most striking difference I have ever heard is with Aleph J. In some systems, it can be quite "uninteresting," good but not the sound that grabs you. Switch the phase of speaker cables. If you don't hear it with this amp, you are immune! If you are happy with your sound, don't hear a difference, don't worry, be happy!
For Pearl 3 I would go eith UDP3 boards. They are specifically designed to work with P3 and are probably the best addition to this wonderful phono pre.
Also drinking similar beers. Pre craft beer days we all had our favs. But was always surprised at inability to spot beers I didn't like. But if you say down to drink several, you'd get wise along the way.
I remember the 90s I had my first separate DAC that had a phase switch on it. I drove myself half nuts and never noticed much difference. Switching speaker wires with AlephJ was very apparent to me.
With age, fortunately I have shed a lot of the Audio Nervous I once suffered for, particularly in the wallet! First Watt products surprise some from lack of "boutique" parts, but then you listen and forget all that BS!
At this moment I’m tackling the current settings .
I need to change the value of both R27 resistors , voltage across both R27 resistors is 2,4 volts .
Is it normal that D1 is constantly lit up ?
I need to change the value of both R27 resistors , voltage across both R27 resistors is 2,4 volts .
Is it normal that D1 is constantly lit up ?