Spare parts left over. Suggestions on what to make?

[smoguzbenjamin]

I got some parts lying all over the place....

4 JRC 072 op-amps
2 10k pots
2 50k pots
SPST switch
DPDT stompswitch
Loadsa resistors
Quite a few caps
10 or so 1N4002 diodes
BF 959 Tranny

I'm thinking of bodging somethin up to boost bass & treble, make the guitar sound a little richer... But I'm not sure if I know how to do that yet...

I was thinking of putting a lowpass and highpass filter in front of seperate op-amps to boost 'em.... But still not sure.

Anyone have sugestions on what to do for these leftover parts?
cheers
Ben  

[Jay Doyle]

If I were you I would read up on EQ stuff at GEOFEX, R.G. has a great article there. You should have enough to build up a parametric EQ that boost bass and treble at specific frequencies and use the SPST switch to add a cap in parallel to one of the caps controling the gyrator's simulated inductance. If this sounds complicated, the theory is but the function isn't. You could set up a stage like the Tube screamer tone control, but instead of having a cap and resistor haning off of the tone pot you can put a gyrator (read the article) instead and make it a frequency specific boost/cut. You can parallel that pot with another just the same but with a different frequency. Using two dual opamps total, one for the tone stage, one to buffer the tone stages output and two for the simulated inductors (gyrators), two 10k pots, the SPST switch to switch in a parallel cap to change one of the center frequencies and your caps and resistors.

One idea.

[ExpAnonColin]

I was thinking some sort of a filter as well.  Instead of making 2 passive ones and then boosting with an op amp, I'd just say make 4 op-amp based filters.

http://www.linkwitzlab.com/filters.htm

-Colin