Tone stack help

[kdawg]

Hello - I am new to tone stack design, but I'm trying to change a tone stack circuit that uses a 12AU7. I successfully tried the new circuit, and tonally it's OK (I wanted to use 1 Meg pots instead of 200K, but I don't have any right now)... but I've lost a lot of gain compared to the original circuit - I'm assuming because it was from a cathode based tone stack, yet my original was anode based. I'm not sure about what voltages I should be having and/or if I need to add something else to match this tone stack. There is 50 volts at the anode into the tone stack, no DC at stack output.

I did try reducing the 220 K resistor and that did get some gain back. Would someone be willing to help me out? Thanks!

Before:
http://picasaweb.google.com/funkymusic/Schematics?authkey=Gv1sRgCP79leLqr-XhfQ&feat=directlink#5309970237323243522

After:
http://picasaweb.google.com/funkymusic/Schematics?authkey=Gv1sRgCP79leLqr-XhfQ&feat=directlink#5309970250318146722

-kdawg

 

[alexc]

Here's a free app you may find useful

Duncan Amps Tone Stack Designer

http://www.duncanamps.com/tsc/download.html

 

[mrphotodude]

http://amps.zugster.net/articles/tone-stacks
there is a great link for reading about/ looking at different types of tone stacks ala guitar/bass amps..
will work on hifi and such as well.
you can pick ideas from there and use duncans tone stack to figure out what values you need.