TDM Distorsion

[fex]

I'm having problems with my SampleCell II PCI and TDM.
The sound comes out distorted (as if I was playing it trough a ring modulator...).
The problem happens kind of randomly , altough I can replacate it every time I use the Virus plug in and Samplecell in the same session. It happens also without Virus tough...The analog outs are always fine.
My setup:
Apple G4 450
256 MB of Ram
Logic Audio 4.5.0
Mix 24 Core card
Dae and Dsi 5.0.1 (same problem with 5.0).

I've deleted all preferences (any Digi stuff)
Pulled out and reseated both cards
Disconnected and reconnected the TDM ribbon cable

I'm out of ideas...
PLEASE HEP!!!!!
Thanks in advance


[This message has been edited by fex (edited December 05, 2000).]

[DigiTechSupt]

fex
Does a new session give you the same
results with only sample cell?
The instruments that you are using
are they the factory library sounds?
Please call us at the tech support line for further troubleshooting and possible repair.
MJ
Digidesign tech Support

[misterbeatnik]

I just bought a used SC2 TDM card on Ebay in January and have the exact same problem, but it's not sometimes, it's always. I've paid my $30 for Digi Tech phone support once (with 3 or 4 free follow-up call backs) and they've told me to do everything from totally erasing my boot drive (1st suggestion) and reinstalling everything to removing all other PCI cards and starting from there. Nothing helps. Tried all versions of DAE/DSI with a minimal extensions set. Tried to use old Samplecell INIT instead of DSI, but Samplecell Editor wouldn't open-just gave an error that said I should try to cycle the CPU power (which didn't help). BTW the audio is also garbage from the analog outputs on the card. Sounds like a pitched sample is trying to play back harmonized up whole step interval, but fizzy and crunchy. My card tests out fine in Samplecell Editor and Digitest diagnostics. They now say it may be bad RAM, but RAM tests out fine and I'm starting to think it's bad software, i.e. Samplecell Editor 2.1.1 for Mac may be buggy. I'm considering instaling the card in a PC (perish the thought) as the next step in troubleshooting. If you've had any luck, please help!

[misterbeatnik]

Okay, I fixed the distortion problem : it was the RAM, as previously conjectured by one Digi Tech. Been trying everything the techs have suggested and finally tried that. I must say in my defense that Samplecell Editor software incorrectly verified the RAM as okay several times. It was the lack of similar problems on the user forum that made me think this is an unusual hardware problem. I removed half the SIMMs and moved the other 4 over, and that gave me clean playback. Have 16 meg of good RAM in there now and I'm so happy I may never bother with the other 16! The guy who sold me the card said it always worked for him, but he might have unwittingly thrown some bad RAM on it to bump it up to 32 meg for the Ebay listing. Or maybe it's all good RAM and some came just a hair loose in shipping. What a hassle to keep tearing apart the computer just to find out! Oh well, that's why we get paid the Big Bucks.

[jeffro]

misterbeatnik -

Glad to hear you solved the problem.

The SC's RAM Test checks for bad RAM, but it doesn't test the RAM's speed. Samples in RAM are constantly refreshed, so if the RAM is not fast enough (70ns or faster) they will distort or get garbled.

If the RAM's speed is borderline, it might work with 2 or 4 SIMMs but 6 or 8 would likely reveal the problem.


fex -

Please try 2 SIMMs at a time to see if you have a bad SIMM. If they all seem to work, build it up in pairs (2, 4, 6, then 8) to see if it's the RAM's speed.

------------------
Jeff Cohen
Digidesign Tech Support