NetNews Usenet Archive 1992 #31/NN_1992_31.iso/spool/comp/sys/ibm/pc/soundcar/5902

Text File | 1992-12-31 | 1.7 KB | 38 lines

Newsgroups: comp.sys.ibm.pc.soundcard
Path: sparky!uunet!cs.utexas.edu!torn!watserv2.uwaterloo.ca!sciborg.uwaterloo.ca!ptran
From: [e-mail] (Phat H Tran)
Subject: Re: On GUS memory (question)
Message-ID: <[e-mail]>
Sender: [e-mail]
Organization: University of Waterloo
References: <[e-mail]>
Date: Thu, 31 Dec 1992 11:09:43 GMT
Lines: 26

In article <[e-mail]> [e-mail] (Damon Harper) writes:
>I may be missing something obvious, but I was just wondering...
>If the GUS needs patches loaded into its memory, how on earth could you have
>(even with 1MB onboard) more than a few short, CD-quality voices in memory at
>the same time?  How could you, say, have a music file with 14.4K voices and
>have any decent number of them at all?  ESPECIALLY without the memory
>extension...  Even if it loads them dynamically, that must be
>time-consuming... and what if you want to have 32 14.4K 10 second voices
>going all at once?  They'd never fit!
>
>-Damon

About 40 high-quality patches can fit into 1 Meg of memory on the GUS.
The reason is that the patches only hold as much information as is needed
to reproduce the instrument with sufficient accuracy.  "Sufficient", in
this case, means "very high".  A patch on the GUS is just the following:

     Start--------------------------------LoopS------------End

Between Start and LoopS is where all the complexity of a natural sound
is.  Between LoopS and End, the harmonics have died down leaving a
waveform that is relatively simple compared to the attack region.  It
is the LoopS to End segment that is looped for the sustain and decay of
a note.  The decay is done through amplitude modulation.

Phat.