Xref: utzoo comp.dsp:733 rec.audio:21923 rec.arts.theatre:150
Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!ncar!umigw!umiami!chuck
From: chuck@umiami.miami.edu
Newsgroups: comp.dsp,rec.audio,rec.arts.theatre
Subject: Re: DSP for feedback control
Message-ID: <6418.267529f7@umiami.miami.edu>
Date: 12 Jun 90 21:44:22 GMT
References: <539@skipper.dfrf.nasa.gov>
Organization: Univ. of Miami (IR)
Lines: 56

In article <539@skipper.dfrf.nasa.gov>, rando@skipper.dfrf.nasa.gov 
(Randy Brumbaugh) writes:
> 
> ...Wouldn't it be possible to use DSP to eliminate feedback 
> in real time before it is noticed?  ...
> 
> So . . . Does such a thing exist?  If not why not?
> It seems  1) possible  2) useful  3) saleable
> Am I missing something?

I've done live sound work for a few years now.  I am certain that many folx 
such as yourself have thought of such a monster, but I have some thoeries 
as to why it's not out yet.  However, it is a *great* idea!

This may not be much of a factor for large sound companies, but something 
like this seems expensive!  The software (and hardware) for this would seem 
to take quite a bit of time developing, and start out costing loads of 
dough, so that the sound quality would not be compromised, and so that it 
would be easy enough for any sound jockey to use.  Although, I'm sure costs 
could be kept within range of most sound-company budgets with some time.

Also, you'd either have to decide on a specific computer to run it on, or 
develop your own CPU, operating system and user interface to run with the 
unit.  And, if you decided on a computer, should it be a Mac, IBM, etc?  
How many sound companies have road-worthy computers?  Sound gear on the 
road gets *real* banged up during load-ins and -outs.  I don't see an 
efficient way of interfacing with a console to control individual input 
gains.  You'd have to build a patch bay of some sort, or a computer 
interfacing scheme to make the whole thing work, and the most efficient way 
for the computer (the interface) is the most "costly" (not just money), and 
the inefficient (patch-pay method) is old technology.  Am I making sense?

I'm sure there are a few other things that hold back this "technological 
wonder".  I certainly see how a profitable sound company could afford some 
machine like this, cause the best way to go would be to buy a console with 
the computer built-in, but this is a great expense.  The ideal way to go 
(so it would be available to everybody) would be to make it interface with 
present boards, and that is a bit more difficult.

I am open to more discussion on this topic, cause I would certainly like to 
see something like this developed!  

> 
> Randy Brumabugh
> rando@skipper.dfrf.nasa.gov

I hope this fuels a little discussion on the subject for ya, Randy.
-- 
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   Chuck Urwiler    University of Miami Music Engineering   Voice & Keys  
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