Friedman Pedals - a circuit comparison

Chuck D. Bones

Circuit Wizard
[edited to add Little Debbie]

PedalPCB carries several Friedman pedals and for good reason, they sound great. My 2nd PedalPCB build was a Brown Betty. The Little Debbie, Dirty Sanchez, Brown Betty, Thermionic and Complex are all basically the same circuit with a few different component values and one or two knobs.

All have GAIN, BASS, TREBLE & VOLUME controls.
Dirty Sanchez, Brown Betty, Thermionic and Complex have a PRESENCE control.
Little Debbie, Dirty Sanchez, Brown Betty and Complex have a MID control.
Brown Betty & Thermionic have a TIGHT control.
Dirty Sanchez has a TIGHT switch.
Dirty Sanchez, Brown Betty and Thermionic have an internal gain trimmer.
Little Debbie has internal trimmers for Tight & Presence.

Thermionic has slightly higher gain and a little more bandwidth for more bite. The Build Docs call out 1N5817 schottky diodes for the 3rd stage. Some people use 1N4148s like in the other Friedman pedals.
Little Debbie, Dirty Sanchez & Brown Betty are in the middle gain-wise.
Complex has slightly lower gain and a mild treble boost at the end (C14/R20).

You can build any of the above on a Brown Betty board. I like having the TIGHT knob, but I think a TIGHT switch will do the trick in most cases. Some folks (you know who you are) like the sludgy sound and will leave TIGHT wide open.

If you want to see a side-by-side comparison of the Thermionic and Brown Betty schematics, look no further than the Thermionic Deluxe. Channel A is a Thermionic with a MID control; Channel B is a straight-ahead Brown Betty.
 
Last edited:

Chuck D. Bones

Circuit Wizard
Yep, everything except the Buxom Boost. I'm planning a Thermionic Deluxe build and I'll mod channel B to Small Box specs.

I forgot Little Debbie! See top post for edits.
 
Last edited:

Betty Wont

Well-known member
Probably, with some frequency tweaking, but I don't think the Friedmans have the gain to get to SLO territory though. The closest by far I've gotten to the SLO is the Soldado project. I heartily endorse its gain and tone structure as authentic feeling and sounding.
 

Chuck D. Bones

Circuit Wizard
Wampler makes a SLOstortion pedal. He uses JFET Mu-amps for the distortion stages and opamps for tone shaping. Here's a schematic from FSB. Not much in common with the Friedman pedal designs. The production pedals contain an independent opamp boost. You can try adding it to the Wish List. Hmmm, I see a breadboard project on the horizon...
Wampler SLOstortion.jpg
 

ErickPulido

Active member
Wampler makes a SLOstortion pedal. He uses JFET Mu-amps for the distortion stages and opamps for tone shaping. Here's a schematic from FSB. Not much in common with the Friedman pedal designs. The production pedals contain an independent opamp boost. You can try adding it to the Wish List. Hmmm, I see a breadboard project on the horizon...
View attachment 10794
I have to try it, I hope I can find some J201 coz smd is a no for me, thanks
 

Chuck D. Bones

Circuit Wizard
I believe that there is a typo on the schematic. C18 should be 47nF, not 4.7nF. Looks like the sweep on the TREBLE control will be better if it's A500K rather than B500K. Some tweaking of R20 may be necessary, depending on Q5's Vp.
 

secretbuffalo

New member
Probably, with some frequency tweaking, but I don't think the Friedmans have the gain to get to SLO territory though. The closest by far I've gotten to the SLO is the Soldado project. I heartily endorse its gain and tone structure as authentic feeling and sounding.
What Soldano project are you referring to? I would love to build a Soldano style pedal.
 

NickC

Well-known member
I have build a thermionic and it sound fantastic, it will be in my live pedal board instead of my xotic sl drive.

in my experiential about high gain amp I can say that the soldano x88r is the tone I am looking for in a pedal and the friedman naked amp circuit would also be interesting ( I've read around that it's based on a Naylor super drive 60)
 
Last edited:
Top