I have owned Bose Hi-Fi speakers (model 901) for many years; the concept behind these speakers was to recreate the sound of a concert hall (small or large) where -according to dr. Amar Bose- the sound that reaches our ears is only 30% direct and 70% reflected (by walls, ceiling, floor, etc). I have always thought that, albeit these speakers lacked the frequency response of direct systems, their spaciousness and their realism were unbelievable.
This is to say that dr. Amar Bose has always been a pioneer in the study of the so called "psycho-acoustic" and I have no doubt that even these PAS are revolutionary, in their own way.
I have tried to follow all the discussion that is going on these days on this stereo/mono issue on different Forums (including Harmony Central) and think that the PAS have brought to the general attention a problem which will change the way manufacturers like Yamaha, Roland, Korg, etc make their keyboards.
Basically I think that we all can agree that when we are listening to a group of musicians performing live cannot just think in terms of "left and right", because there is also a "up and down", a "front and behind" and all the intermediate degrees between them, and this is exactly the reason why, after listening to one of those home theater systems (5+1 or -even better- 7+1) nobody can go back to a simple stereo system without feeling a sense of deep insatisfaction.
So, like Mike asked, why are the people at Yamaha, Roland, Korg, etc selling keyboards with sounds sampled in stereo? Well, maybe because they sound more spectacular than a sound sampled in mono, at least until somebody comes up, even in the PA field, with a revolution comparable with what the surround systems have represented for the home listeners.
At this point, on the basis of the keyboards and samplers currently available, I have another question: what happens if I sample a piano sound in mono and then pan it according to the key played (bass notes on the left, mid notes on left + right, high notes on the right)? What's the difference with a sound originally sampled in stereo? In both cases, when I play a note, the sound that reaches my left ear is different from the sound that reaches the right ear. So, is it possible that -aside from saving 50% of the internal memory- sampling a sound like a piano in mono will give a more natural result, maybe because sampling the same piano in stereo can introduce artifacts, and the phase cancelation problem is just one of them?
I would like to know if anyone here has ever tried to play a monophonic piano multi-sample, panned according to the key and routed through a good digital reverb: what's the difference with a stereo multi-sample? Is the former less spacious or less natural?
I have a feeling that the people at Bose have just opened a BIG can of worms...