ASM-1 VCF breadboarded using +/-12 volts

[Christopher MacDonald]

Hi all,

I wanted to take a break from the diode filter for a while so I decided
to try breadboarding an ASM-1 state variable filter.  After some
struggle (fried a 3080 somehow) I have it fairly well tamed.  In order
to make it work with a +/- 12 volt supply I had to change R21 and R26 to
1k as well as making R23  and R28 10k.  These values were arrived at
empirically so I can't vouch for their theoretical correctness.

The only problem I am having now is that, with moderate resonance
settings, I can't put more than about a 0.4 volt peak-to-peak wave
through the filter without some fairly ugly distortion.  Does anyone
know if this is typical or is there some other modification I need to
make?

If it is normal, I am considering increasing the input resistor value
and giving the output op-amp buffers some amplification.

Any advice would be appreciated.  I would really like to complete a new
module sometime soon!  :-)

-Chris MacDonald