Hi again,
Here are some results for the first half of the circuit which reflects the bass and treble. If you think this is good we can go from there.
I managed to get the first half of the circuit into pure equation form so i can analyze the response for any combination of resistors or any frequency in a matter of less than a second each, over three or more pot settings for each pot. So if you have a certain set of resistor values you'd like to try just post the values here and i can run the equations. You'll get output data for various pot settings.
I suppose i could turn the equations into an interactive Windows program, but that's going to have to wait.
The following data is organized with all the resistor values first, then a table that shows the frequency response for two different frequencies 45Hz and 10kHz, which are most interesting, and that data is shown for three different settings of both pots as indicated, where each pot (one side) is set to either 0k, 10k, or 20k, as shown. The gain is then shown in db to the far right.
The first data set is with all resistors at their current values, that is, unchanged.
The second set is with some resistor value changes which show a boost in gain for both bass and treble, but some loss of cut for the bass.
Check these out and see if they look good. If you think they are what you want, try them and see how you like the sound.
The data:
Code:
FIRST SET:
R13=100000
R15=27000
R16=27000
R17=6800
R18=3900
R19=100000
R21=2700
R22=6800
R23=3300
TREB BASS
R20a= 0 R14a= 0 freq= 45 -7.5 dB
R20a=10 R14a= 0 freq= 45 -8.1 dB
R20a=20 R14a= 0 freq= 45 -8.2 dB
R20a= 0 R14a=10 freq= 45 15.4 dB
R20a=10 R14a=10 freq= 45 15.4 dB
R20a=20 R14a=10 freq= 45 15.4 dB
R20a= 0 R14a=20 freq= 45 21.9 dB
R20a=10 R14a=20 freq= 45 21.9 dB
R20a=20 R14a=20 freq= 45 21.9 dB
R20a= 0 R14a= 0 freq= 10000 -1.7 dB
R20a=10 R14a= 0 freq= 10000 15.7 dB
R20a=20 R14a= 0 freq= 10000 22.3 dB
R20a= 0 R14a=10 freq= 10000 -1.3 dB
R20a=10 R14a=10 freq= 10000 15.7 dB
R20a=20 R14a=10 freq= 10000 22.4 dB
R20a= 0 R14a=20 freq= 10000 -1.2 dB
R20a=10 R14a=20 freq= 10000 15.7 dB
R20a=20 R14a=20 freq= 10000 22.4 dB
NEXT SET:
R13=110000
R15=32400
R16=54000
R17=6800
R18=3900
R19=100000
R21=2700
R22=3400
R23=3300
TREB BASS
R20a= 0 R14a= 0 freq= 45 -0.5 dB
R20a=10 R14a= 0 freq= 45 0.4 dB
R20a=20 R14a= 0 freq= 45 0.6 dB
R20a= 0 R14a=10 freq= 45 17.1 dB
R20a=10 R14a=10 freq= 45 17.3 dB
R20a=20 R14a=10 freq= 45 17.3 dB
R20a= 0 R14a=20 freq= 45 26.3 dB
R20a=10 R14a=20 freq= 45 26.8 dB
R20a=20 R14a=20 freq= 45 27.0 dB
R20a= 0 R14a= 0 freq= 10000 -1.5 dB
R20a=10 R14a= 0 freq= 10000 19.1 dB
R20a=20 R14a= 0 freq= 10000 26.7 dB
R20a= 0 R14a=10 freq= 10000 -1.2 dB
R20a=10 R14a=10 freq= 10000 19.1 dB
R20a=20 R14a=10 freq= 10000 26.8 dB
R20a= 0 R14a=20 freq= 10000 -1.1 dB
R20a=10 R14a=20 freq= 10000 19.1 dB
R20a=20 R14a=20 freq= 10000 26.8 dB