re: Help!! - Sync trouble
Rich Gorde
11:11 am sunday january 9, 2000
Tom..

Thanks for the kudos, they are greatly appreciated.

I'll preface this by saying I do not own a 1212 I/O card so have
no specific experience with it.  A few of the people that visit
this board do have them.  But they may visit here infrequently.
Because the response time out here can tend to stretch out, let me
share my experience with sync.  Maybe it will help relieve your
frustration.

I'm sure that someone somewhere is setting up CWPA differently but
I found this to be the _only_ way to get my system to work
reliably (168 + sonorus studi/o) with CWPA.

a)       CLOCK
Set the sound or interface card to be the master timekeeper. Sync
all external clocks to it.
The sound or interface card physically generates the interrupts
that request it be serviced by the computer.
If you have the sound or interface card 'chase' an external clock
you are more prone to stumble.  Let the card and it's driver "do
it's thing" at it's own pace.

Sync the 168RC clock via the lightpipe input..  I use digital "B"
but it should not matter.  Word clock will brute force sync but
that should only be necessary if you start adding other digital
devices that also have to be brought in step.

b)       CWPA 8.04
Run the profiler.  This basically runs a timing diagnostic and in
many cases (like the 1212) sets up default buffer offsets and
sizes. You should not have to alter the settings.
Assuming you are not trying to sync to SMPTE:

In CWPA under the TOOLS tab,  AUDIO OPTIONS,  ADVANCED try these
settings:

ON       Enable Simultaneous Record/Playback
ON       Use Wave Out Position For Timing  (the 1212 determines all
the timing based on it's ability to output data)
ON       Trigger and Freewheel  (Full Chase Lock OFF) = ignore
SMPTE or MTC.

A note on the SMPTE/MTC sync. The CWPA Help screen says selecting
Use Wave Out position defeats these options.  I have found in
previous versions that _NOT_ to be true.  There still was some
interaction.  Interaction as in "out of sync".  Humor me and check
"Trigger and Freewheel".

Barring any erroneous 1212 driver settings, this should lock your
sync.

* DROPOUTS *
Once your tracks are synchronized the next gremlin to squash is
the 'dropout'.

Basically it's a case of "feeding" the audio interface card
reliably.  Number of tracks, CPU speed, disk speed.. how
fragmented your audio files are can contribute but should be last.
When I used an SB16 and Tahiti card on a 486DX-100 under CWPA 5
and 6 I was able to get a dozen audio tracks before rolling over.
Before you start playing with the various buffer size options in
CWPA read through this:

If during playback you either 'just suddenly stop playing' or
completely 'lock up' then it is a hardware conflict.  Not
necessarily INT or DMA related, but it's a good idea to comb
through them to make sure there aren't any obvious problems.

I have found every version of CWPA to be extremely sensitive to
having video card graphic acceleration enabled. This is especially
true if your interface and video card both live in PCI slots.
These devices tend to hog the PCI bus exclusively when they get
hold of it. Especially a vid card that is trying to move huge
amounts of data through the bus. It's best to dumb down the vid
card.
Test while using less and less of the vid card accelerator
functions.  Find the control under Windows "System Properties"
(right click on My Computer.. then properties), in the '
Performance' tab,  Graphics.  I have found that I have had to use
one notch of acceleration "Basic acceleration functions".  This
has been with a variety of vid cards, motherboards and a handful
of audio cards.

My audio system (Celeron @ 450mhz) had been running flawlesly
under 8.04.  Upgrading to CWPA v9.0 I spontaneously developed an
audio dropout problem again. Not only that.. I could lock my
machine up.
The only way I could stop it was to disable the drawing of audio
waveforms during playback.  Adding "DrawPlayingAudio=0" to the
initialization file solved that.  Proves the old CWPA addage..
"Give a little, Break a little".

CRUNCH TIME
To test my system settings.. I load a file with above average
number of tracks.  I set to loop across most of the song.  I bring
up an audio view with all tracks visible and zoom set so I can see
2 or 3 measures.  I start playback and let it run.  I have found
this the best way to test video/audio card conflicts.  This is
also how I discovered that in CWPA 9 I could not redraw waveforms
as reliably as in 8.04.  If you are going to have a problem.. it
will appear here.. and it's very repeatable.
After a pass or two (yeah!).. turn down the monitor volume and go
do something else.  Leave the room (or you will learn to hate your
song!).  Let it run for 15 or 20 minutes even longer.  If it's
still running when you return then mouse around and open and close
track view etc. while it continues to run.  It may crash on you
but its better to find out what you can or can't do.

OK Tom.. well I'm nursing a cold and really didn't feel like doing
much of anything else for the last hour.  Take care.

Rich
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