Apparently-To: john.smith@gravis.com


GUS Programmer's Digest     Mon, 29 Nov 93  4:48         Volume 6: Issue  16  

Today's Topics:
                      ARGH!  More UltraClicking

Standard Info:
	- Meta-info about the GUS can be found at the end of the Digest.
	- Before you ask a question, please READ THE FAQ.

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Date: Mon, 29 Nov 1993 01:15:22 -0500
From: Greg Chung <gchung@pegasus.rutgers.edu>
Subject: ARGH!  More UltraClicking

Okay, maybe I'm dense, but I've not yet resolved the UltraClick problem which
just about everyone else seems to have written off.

However, since I know I'm not the only one who is having problems, please be
as patient as you can.

Now:  I'm playing back a .MOD, so I've got at least four voices playing
multiple samples.  No big deal here.  But!  I've got start-clicks, end-clicks,
and loop-clicks.  My looping addresses seem to be set up in the right places,
so I assume that loop-clicks are due to bad sampling.  If I do some 'fudging'
of the digital data at the loop-point, I might be able to soften the click.
Any thoughts?

As far as starting clicks:  I have the volume set to a low level.  I then
begin a ramp up to the regular volume.  While the ramp is going, I start the
voice.  I've experimented with different ramp rates but haven't found any
one best speed for all samples.

Ending clicks:  I set the sample to play almost up to the end of the sample
(sample length - 32 bytes) and generate an interrupt.  At the interrupt, I
begin a volume ramp down and finish playing the rest of the sample.  This gets
rid of a lot of clicks, but not quite all of them.

Ok, here's my other related thoughts.  The GUS sums up all voices all the time
even if they're not playing... I tried running the player by stoping, then
priming the voices (as usual) but not actually starting (GoVoice) them.  The
'Prime caused a click if the volume was high enough to hear it.  I assume this
means I have to change my procedure to first zero the volume, THEN prime the
voice, then start a volume ramp?  

As far as house-keeping goes:  at the end of a sample, I StopVoice and set the
volume very low.  I'm not actually relocating the voice to a zero-location
because at very low volume it really shouldn't matter, should it?  My only
thought is that when moving a voice location (eg Priming) a click might be
generated depending on the contents of the previous location?

------------------------------

End of GUS Programmer's Digest V6 #16
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