[net.audio] Live Sound

wjm@whuxj.UUCP (MITCHELL) (02/09/84)

I cannot agree too strongly with those recent articles posted here that
emphasized the need to listen frequently to LIVE music.  I try to get to
live concerts (mostly at Carnegie Hall and Lincoln Center in NYC) several
times a month (I'd go more often if it wasn't as much of a trip into the
city from out in Jersey) to recalibrate my idea of what music should sound
like.  To me, the optimal high fidelity reproduction system would give the
listener the impression of being about 2/3 of the way back in the orchestra
in a hall like Carnegie Hall or Symphony Hall in Boston - but that's my
personal preference, just as my tastes in music tend to favor the classical
side of things.  However, I'd like to be able to change the settings to
reproduce a smaller room for small chamber ensembles (like string trios and
quartets) since I also enjoy listening to chamber music. 
So much for the ultimate ( I can dream, can't I ?? :-) ).  Now the question
is, given a finite budget and the constraints of technology, how close to it
can we come?   As I read the hi-fi magazines each month, I'm both pleased and
upset.  I'm pleased by the advances in technology that make it posisible to
come closer to this goal, but I'm upset by the bad things that are done 
(like noisy recordings and multi-miking).  Since the goal of high-fidelity
is to accurately reproduce a live performance,  one must listen to LIVE
performances OFTEN to KNOW what it SHOULD sound like.
As I've said many times, as an engineer, I feel that any distortion from
the live sound is due to quantifiable parameters (although we may not know
what these parameters are at the present time), but one can have a "gut feel"
that SOMETHING is wrong without having to make a large series of lab tests,
This feeling is generally caused by knowing that recording X does NOT sound
like a live performance, and one can then go into the lab and find out why.
As I've said before, certain digital recordings (Denon's in particular)
do not sound like live music.  At the present time, I don't know what
parameter of their recording process is causing the problem (although I suspect
it is due to their 44.1 MB sampling rate lopping off some harmonics, and the
noise introduced by their 14 bit encoding).  On the other hand, Telarc's
recordings sound quite realistic.
Bill Mitchell
CSO
Whippany, NJ (whuxj!wjm)

pmr@drufl.UUCP (Rastocny) (02/10/84)

Bill,

There was an excellent article in the "Computer Music Journal," Vol. 7,
No. 3, Fall 1983, by F. Richard Moore that described a good model
for what you are talking about.  It relates two loudspeakers to
two holes cut into the walls of a small room that is within a much
larger room.  Basically, the only perceptions that you have of what is
happening in the outer room is via these two holes (speakers).  The
article is quite lengthy and deals with several interresting topics on
loudspeaker placement, virtual acoustic space, radiation vectors, early
echo patterns, and global reverberation all related to Cmusic but
totally applicable to stereophony.

Good reading,
Phil Rastocny