Simple 3-Band EQ schematic?

[Jasonmatthew911]

Hi guys, I'm just wondering if anyone here can give me the simplest 3-Band EQ schematic that I can just insert on the output of an Opamp Overdrive circuit I'm about to make, but I want to replace the Tone knob and have control of my Bass, Mids, and Treble...I searched it, and found some options, but I'm just wondering if anyone here knows of a simple 3-Band tone-stack that requires the least extra parts?...The overdrive circuit uses enough parts as it is, so I don't have a lot of board room for 3-Band EQ parts...I have to do it as simple as I can...Let me know, thanks.

[Ben N]

You can use the standard MBT tone stack from a Fender or other amp---BUT, you will lose a lot of signal strength, which you will want to get back with a recovery stage.

[samhay]

As Ben said, you will lose a lot of signal, but it has been done before.
e.g. - take a look at the Marshall Drive Master.

http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=44736&g2_serialNumber=2

[GibsonGM]

You can use the standard MBT tone stack from a Fender or other amp---BUT, you will lose a lot of signal strength, which you will want to get back with a recovery stage.

Yes - if you start at say, R12 on the schematic samhay posted - you'd have lost a lot of signal by the time it leaves the treble control.  So you'd NEED to have a recovery stage.  Tone stacks eat decibels!   

It could be as simple as one transistor, done up like the last stage of a Big Muff.    1 transistor and what, 4 R's, 2 C's....you can fit it in there  

[Jasonmatthew911]

Ok great, I'll look into this, thanks guys!

[LucifersTrip]

[gjcamann]

Here are some options that can be incorporated the op amp.
http://www.muzique.com/misc/AMZ_tone.pdf
There's also a half dozen links to articles on tone controls here too.
http://www.muzique.com/lab/main.htm