Circuit alteration for preamp

[Skywalker83]

After a little chat with a very kind gentleman on an electronics forum , the problems have been sorted out.

This is the finished active circuit.

The input stage comes from [Invalid or Expired Link Removed] guitar preamp circuit (bottom of page), so i may need to tweak values. R3 and C1 might need to be removed or changed if certain problems occur.

The EQ stage, i'm actually not sure what the frequency values that will be altered for each band are. This set up came from a Mixer styled EQ,so i'll presume for now that it's set up for common cut off points for each band.

The next stage is to get the schematic onto a small enough PCB so that it will fit into the cavity (along with the passive electronics )

The software i've been using is ExpressSCH, and will be using ExpressPCB for making the PCB layout.

 

[slyjoe]

Are you sure you want the mid controls to come straight off the input? Why not on the output of the first buffer stage?

You may want to review circuit 4 on http://www.all-electric.com/schematic/mix-eq.htm. It looks to me like that is still the same essential circuit you are shooting for.

Just my 2 cents

 

[Skywalker83]

The Mids are controlled from the output

Mid and Freq are fed from the output of IC1b which is the Bass and Treble opamp.
R16 connects to "half the supply voltage" (C1) which is DC and biases IC2a.

 

[slyjoe]

I see - missed the voltage divider.