A few years ago in this very thread he was asking questions and being politely answered
Specular reflections don't have gain - only those that add coherently can produce the necessary non-minimum phase behaviour to generate "gain". But some degree of blurring is ESSENTIAL in conventional stereo reproduction to overcome its inherent combing. By compensating for the 6dB/octave roll-off in low frequency energy, however, the need for late lateral energy is offset to a large degree. These flaws of stereo reproduction are best addressed first by compensating for their cause, rather than by toying with directivity and room treatments.
Just reading back a bit, I must have been thinking of his posts in another, or other, very similar thread(s) as well lately
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That's good, since my invitation to Toole's house must have gotten lost in the mail.
Quite frankly this audiophilia nervosa thing hasn't brought me much joy, my ears are still ringing from my last project.
@Polk. It's funny, I can totally separate it from the enjoyment of music with no effort, believable (to me) reproduction can add pleasure but it is far from number one priority. It interests me that a good sounding system increases my enjoyment of Jelly Roll Morton, yet many say a good system makes poor recordings sound worse, I really cannot get my head round that statement??
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I guess u mean the opposite, if speculars are coherent they are minimum phase or
A specular reflection will always have lower energy than the direct sound due to the inherent losses in a reflection. A room response comprising of only specular reflections would theoreticlly decay monotonically to zero. As such the "room response" would be minimum phase. A single room mode (standing wave) might behave as such.
Where two or more such reflections add coherently, however, their combination can lead to a room response that does not decay monotonically and will therefore be non-minimum phase - at least at a particular set of frequencies. (Strictly speaking a response is either minimum phase or not, but we will ignore that for the time being).
This is actually more important than the dull theory makes appear... For a start, it can be shown from here that the probability of non-minimum phae behaviour rises with increasing frequency - which is exactly what happens (in general, but not always) as we move from the standing wave frequency band at LF into the diffuse frequency band.
For those hoping for equalization of a room response that deals with room modes, it is good news, since a minimum phase response has a stable inverse. That is unless your room has closely spaced dimensions or your most excited room modes are higher up in frequency (which incidentally can be more frequent in non-rectanglar rooms).
For those hoping for compensating for the "suckouts", however, there is little hope with a single channel. Instead we need some parallel equalization channel such a case, where we find the matrix of filters needed for compensation can be arranged that even where individual responses are non-minimum phase, the equalization can still be stable!
As we move up into the diffuse region, however, and non-minimum phase behaviour increases, so wavelength decreases. Without discrete standing waves to compensate, we are stuck with near-specular zones of equalization, outside of which the response is likely worse than before equalization is applied - even between the ears.
But my rambling is not so off-topic... As I have alluded to many times to try and get the ball rolling in this thread, in stereo reproduction, it is not at all desirable to compensate for the (whole of) the room response - or have an anechoic room. Instead the non-minimum phase behave implies diffuseness, which is the ideal room response to compensate for the comb filtering imparted by having two widely separated stereo loudspeakers.
And one last time, if you are missing "spaciousness" or "envelopment", try boosting back the S channel to that it was before it was sampled by the microphones. There is information in stereo recordings that is seldom heard - and whatsmore it doesn't need you hire an "expert" or someone selling "snake oil" to find it.
In passing, I would also add something that is often overlooked: M and S channels in stereo excite different room modes. That variation (I suggest) means that we might find it more difficult to disassociate the room response from the information being replayed in such cases. This bit I never investigated. But I will say again, it has never ceased to amaze me how the best mastering engineers are able to disassociate the room and loudspeakers from what they produce. It is not always the case, however...
Big thanks, knocking on the table. Such posts remind me why i signed up here.
No thanks needed, but thank you for the thank you!
Countering my own post somewhat, I would recommend checking out the very expert opinion of the late Michael Gerzon re stereo shuffling for starters and hear for yourself some of what I have tried to describe. Coincident miked stereo, shuffling and narrow-angle compensated stereo can realise an amazing listening experience that is seldom exploited - and often not masked significantly when used in conjunction with adequate room acoustics and reasonably engineered loudspeakers. DSP makes it a whole lot easier and even more exact.
I can separate it, but not while I'm still trying to figure out what's going on. I guess that would be critical listening.
Its interesting that I can listen to my oem car system and never get annoyed by it. It would be considered low fidelity, but I can tune it in and tune it out.
I think its a dispersion issue because the car system has the high frequencies pointed up at the windshield, so the sound bounces off it.
The main driver is this thing, I think its just a cheap paper full range
Km503194 02-03 Toyota Camry Dash Board Tweeter Speaker JBL (86160-aa390) OEM | eBay
I think some muscians have hearing damage and also don't account for baffle step so they put too much mids when they mix it.
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Agreed. Good sounding masters are surprisingly versatile in many type of context. In my opinion, mono recording masters are more forgiving in general, I notice less difference in different rooms.
PS: I meant to say it's easier to separate room and source with mono recording, so I can hear the source (or speaker, room) clearly in given context.
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Which goes back to what he said about stereo comb filtering, Toole talks about it at length too
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