Stuck notes and noisy attack transient

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zeropoint
 
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Stuck notes and noisy attack transient

Post by zeropoint »

Hi everyone,

I built my x0x a while back and had it working fine. It's been on the shelf for a couple of years, though, and now some problems have appeared. I went over the boards rehitting dodgy-looking joints and scraping excess flux residue, which cleared up a couple of other problems, but two issues remain:

1.) Notes persist indefinitely. I tested the gate out and it seems to work correctly, and D35 and D36 exhibit the correct behavior as well.

2.) There is a loud thump when notes trigger, which manifests as a staticky click when the accent is up.

Thanks in advance for any help narrowing these down!

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antto
 
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Re: Stuck notes and noisy attack transient

Post by antto »

can you record an audio sample so we can hear/see

zeropoint
 
Posts: 22
Joined: Sun Feb 01, 2009 2:43 am

Re: Stuck notes and noisy attack transient

Post by zeropoint »

Thanks antto, sure, here's a sample! This is in keyboard mode. Now that I listen more closely, the thump occurs whenever I press OR release a key (and I'm not quite sure, but there might also be some white noise that sustains while the key is depressed). Interestingly, prior to this the x0x had been starting up with a note already sounding, but now it is silent on startup until I hit a key - and the first note hit has an odd warble to it. That may just be because I didn't give it time to warm up, though.
x0xtest.mp3.zip
(321.37 KiB) Downloaded 69 times

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antto
 
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Re: Stuck notes and noisy attack transient

Post by antto »

i see now
that's DC-offset in the VCA, which gets amplified together with the audio from the vcf section
and the volume envelope doesn't decay to zero but stays open (could also be DC-offset there as well)

zeropoint
 
Posts: 22
Joined: Sun Feb 01, 2009 2:43 am

Re: Stuck notes and noisy attack transient

Post by zeropoint »

Right - turns out the BA6110 wasn't firmly seated in its socket… Everything seems to be working fine now -- though volume on mix out is kind of low. If I dial the volume pot back to halfway it becomes almost inaudible. Headphone out is just fine. Any thoughts about what might be causing that (or is it normal)?

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