x0x background noise how much is normal?

by crx091081gb on Sat Mar 23, 2013 6:16 am

My x0x seems a bit noisy, like there's an an unfiltered copy of the oscillator playing quietly in the background. It's most obvious when I have the cutoff and resonance turned low. If I leave the env mod and adsr release turned high (I have the x0xi0 front panel mod installed) then you can hear it on it's own.

Is this just regular vca noise or is something bleeding through that I can get rid of?

Here's a sample with env mod and release high but the cutoff and res low. It persists as long as I hold down the key in keyboard mode so it must be vca/gate related.

http://crx091081gb.net/x0xnoise.wav
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Re: x0x background noise how much is normal?

by antto on Sat Mar 23, 2013 2:37 pm

i only see a sharp edge "leaking out" after the VCF (filtered) signal
this edge repeats with ~81Hz frequency which also seems to be the VCO frequency, and can't be due to mains hum..
so i guess you got the sawtooth "spike" leaking out after the VCF.. and i think it's also after the VCA even
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Re: x0x background noise how much is normal?

by crx091081gb on Sat Mar 23, 2013 2:58 pm

I fixed it, it was due to the VCA input mod I'd installed, the cable is very susceptible to picking up the raw oscillator sound. I went back through the updated x0xi0 install notes and found it. All better now. Cheers for replying tho.
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