Moog filter 12V

[robboten]

I recently built a minimoog filter from yusynth. It works quite good but I'm a bit unsure if what I see is a feature or a problem.

First of all. Square waves that passes thru becomes almost like the letter N when no resonance. With more resonance the square is more as it should be but filtered. I looks a bit like this -

The second thing is that the volume changes quite a bit when the resonance is turned up. Not a huge problem but I'm just curious how much it is supposed to change.

My third question is that the self oscillation does not make a sine wave but a square wave (if that is whats input) with sines. I also get the feeling that the cutoff is a bit too narrow mayby. It looks like a bit the third image here when full resonance. [img]http://www.regonaudio.com/Rep.%20of%20Square%20Wave.bmp[/img]

I have built it around 12V instead of 15V but otherwise the same components (3046). Is this the source of these pecularities or should it be like this? And if it is a problem and not a feature, what can I change?

[robboten]

I think one of the problems was that the input setting was very sensitive. The self-oscillation is solved with this and some tweaking of the trimpots.

The problem left, which is quite annoying, is the volume changes. If it was just a small amount it would be ok, but now the volume goes down quite a bit if resonance is turned up. At input pot at twelve a clock for example the Voltage p-p is 7.6V when resonance is off. At full resonance the p-p voltage is only 2.4V. At full input p-p voltage with res off is 8.8V and full res still 2.4V. Is there any way to fix this?