Yes and no. I don't think Griesinger has such a clear focus on stereo as to state that early reflections degrade 'imaging' (which is a marketing term only, btw)).
You make of 'imaging' what you like, I do not share that opinion. Griesinger didn't speak about Stereo at all in this particular video. It's all about perception of humans, and mostly related to halls etc. He has way more work than this though, but that wasn't the point of showing this particular video. What is the point is that he stated: human phase detection works over a larger part of the frequency spectrum than was previously assumed.
Agreed, but Griesinger doesn't address the widely inevitable 'phase distortions' as they appear in speaker-tech. What I read was all about early reflections, which, to begin with, come from other directions than 'phase'. To take his honourable work as proof for silly 'audiophile' nonsense is the evil deed I'm talking about.
Think a bit harder, you're not quite getting it why I showed the video. Now his work has been upgraded to 'honourable' work, at least that's something worthwhile. I didn't get that same impression from you in your earlier replies. Well deserved though in the case of Dr. Griesinger.
Read all (global) reports of people that have studied the audibility of phase rotations induced by crossovers. The most
often stated reaction: sure I've heard some tonal differences, but that was only minor. I don't even know which I preferred.
Now go back to the Griesinger studies/video and see what he has to say about our ability to detect pitch and the role of phase:
Griesinger paper said:
Onsets of speech and musical sounds are far more important to comprehension than the way sound decays. The small segment of direct sound that carries with it accurate information about the timbre and localization of the source is often quickly overwhelmed by reflections. To predict acoustic quality we need to know under what conditions precise data on timbre and localization are lost.
Our ability to separate the harmonics in the vocal formant range from two or more sources at the same time depends on the phase alignment of the harmonics from each source. The phase alignment of the harmonics from each source creates amplitude modulation of the basilar membrane at the frequency of each fundamental, and these modulations combine linearly. The brain stem can separate them from each other and from background noise by their pitch.
Would you think it is easier to recognize pitch when played back with a pure minimum phase system or one that has phase rotations due to crossovers, most probably at crucial points in frequency? Think back about those differences people observe in the tests done on the perception of crossover phase rotation. I know which one I would gamble on being "more correct". As long as the means to come to that result don't disturb or destroy the main pulse. So be aware of things like pré ringing. It's better (if you can) to avoid it.
And Griesinger said about reflections:
Griesinger paper said:
Reflections from any direction alter the phase relationships between harmonics of complex tones, reducing and randomizing the amplitude modulation of the basilar membrane. The result is intermodulation between sources, distortion, and noise. Separation of sources by pitch becomes difficult. The brain stem must revert to a simpler method of decoding sound. The sources blend together, and only the strongest of them can be accurately perceived and localized.
I know and realize he's not talking about Stereo reproduction, but the workings of human hearing
is important if we want to maximize listening pleasure. If we allow early reflections we sure know we won't keep those harmonics in check that allows us to hear separate voices, instruments etc. I say it is as bad an idea as it is in the halls made for listening to concerts. Same goes for the phase rotation, if we don't have to have this rotation, we keep the signal more true to the source. As long as the way we can unfold the phase, or even avoid the rotation does not degrade the onset of those sounds that form the "close proximity". You'll have to excuse my English, I'm not a native English speaker. What I do is maximize my 'shot' at the direct sound, very low levels of reflection, very low diffraction, and following minimum phase.
I myself experimented with highly directional speakers and added quite late, diffuse adjustable reflections from the room. This was documented here, no interest--at all!
I haven't done or said anything to generate interest, weather I got it or not. I do what I do to learn, I share it because the following discussions trigger new experiments to learn more. But I understand the lack of interest. It happens to me too. Valuable research like that of Dr. Griesinger should also attract more attention i.m.h.o.
I do add ambience, virtually created. Using additional tools created by Dr. Griesinger (Lexicon Random Hall plugin).
Good move! And likewise that's the essence of my caveats. Forums mislead people due to lack of ... personal responsibility maybe?
If phase rotation audibility is valid or not is only part of the whole story of Stereo perception. We have to deal with inter-aural crosstalk when listening to speakers in a Stereo triangle which also doesn't make things easier. But instead of simply denying the ability? I'd rather welcome people to make up their own mind, should they be interested. On this forum I notice an almost blind following of the teachings of Toole. Yet, after studying the various parts of our hearing system and the way stereo works, I've come across a lot of contradictions. Dr. Geddes always said: (early) reflections degrade our capability of imaging. You can call it a marketing term, I've come to appreciate it, as the more I have learned and applied to my room + speakers (as a system that works together), the more enjoyable it became. Before that happened, I could care less about imaging and everything that was important to me was tonal balance and dynamics. These two still land higher on the list than imaging, but boy is it fun if you (can) get it all at once!
And again I feel deficiant, in that my ability to enjoy the most precious stereo equipment is retarded. At least that fits my mental abilities, sure. So I'm left with sitting on my friend's grand piano getting Schubert's songs explained. Pity me, with stereo I neither feel immersion nor involvement
I can't and won't speak for you. For me, music ranks up there as one of the most important parts of my life. Be it the live music I've been fortunate enough to witness or the joy of hearing good music (and being able to enjoy it) on a Stereo. That enjoyment of Stereo went way up, the more I learned about it and the more I could detect
and influence this crazy, slightly broken "invention". The soundtrack of my life has been 'locked up' into this Stereo format, the music that I love, hold dear and have an emotional connection with. So I've decided to find "my way" in this puzzle of sound, to maximize my listening pleasure. To do so I've build my own speakers, changed up the room within the rules set by my spouse and started working/thinking
and applying all I could come up with to really max out (my) listening pleasure. Dare I say I've accomplished more than I ever could imagine in advance.
One thing I promised myself: Don't get caught up in the game of building several speakers, instead choose one you believe in and optimize that. Keep playing the songs you love. Those are the songs that count! I
need to be able to enjoy the "soundtrack of my life". That's the whole point, for me anyway.
The system doubles as a HT capable system and I'm actually starting to appreciate that too!