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Oscillator problem?

Oscillator problem?

2002-11-11 by jpyn8

Earlier today I decided to start with a 'basic' patch and work my way 
through every single parameter in order to learn how things work. I 
didn't get very far because I discovered a potential problem with the 
two analog oscillators - they sound different even when I've 
programmed them exactly the same.

OSC 1 seems to act as it should, but OSC 2 tends to make some noises 
that I don't think should be there. I can only explain it as a sort 
of "digital artifact" that appears to be slightly delayed. I've 
checked everything to make sure there are no Delays or Feedback loops 
programmed in. 

I've made two short soundfiles demonstrating this:

http://www.absynthinteractive.com/evolver.htm

- OSC 1 - this is how it should sound
- OSC 2 - you can hear the noise on most of the hits...at one point 
it almost seems to cut out and jump back in, sort of like a "shorted" 
electrical wire.

You might have to crank the volume up to hear the difference, or use 
headphones. Also, I'm pretty sure that it's happening in the 
oscillator because I can split the two left and right, then reverse 
the image (using the VCA Output Pan) and the noise follows OSC 2 
wherever it is panned instead of staying on one channel.

Here's a little more info about what's going on iin those samples. 
Both are set to C1 and a Pulse wave set at 50 for "square". The OSC 
Levels are both set around 78 or 79 because this is the point where 
OSC 2 begins to introduce this noise. OSC 1 will do it too, to a 
lesser extent, if I turn up it's Level to around 91 or so. Now, to 
me, this would indicate that I'm overloading the signal path 
somewhere, but get this: I can turn down the Level of OSC 2 to the 
point where the noise goes away, but then if I start to turn the VCA 
Envelope Amount DOWN from 100, the noise shows up again...if it's 
overloading a circuit somewhere, it doesn't make sense that it gets 
worse when turning the volume down like that.

Anyone else axperienced a difference between OSC 1 and OSC 2? I 
apologize for the long-winded explination, but I'm trying to describe 
it as best as I can. I'm 99% certain that I've turned off all of the 
usual suspect parameters, such as Feedback, Delay, Hack, etc.

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