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Hey does anyone have a schematic for the EHX Freedome Preamp pedal? I've seen snippets that make it seem different than the preamp for the actual Freedom Amp. Looking to cop some Reis tones on a budget.

Not at all what you are asking for, but this popped up on Ebay yesterday:http://www.ebay.com/itm/301281915464?ssPageName=STRK:MEWAX:IT&\_trksid=p3984.m1423.l2648The actual Freedom Amp.Both FM bleh. and myself have picked one up recently, and it is definitely Reis tones, and budget.

BTW, found this:http://www.freestompboxes.org/viewtopic.php?f=1&t=16394Looks like FM Dr Tony Balls is your man to talk to.

gjhardwick wrote:Balls Freedom Amp Preamp"Free 'n' easy, Lis - there's nothing like an unfurnished basement for pure comfort."

caset wrote:BTW, found this:http://www.freestompboxes.org/viewtopic.php?f=1&t=16394Looks like FM Dr Tony Balls is your man to talk to.So I started to attempt a trace of one of these many years ago using gut shots found online. I didnt get very far at all before one of the old guys on the FSB forum posted the schematic. However, his web-hosting appears to be down so the schematic isnt around anymore and I dont think I ever printed out a hard copy. I'll try to dig around with the forum members there and see if anyone has it or knows what happened to the original poster.gjhardwick wrote:I reckon they'd be at least a couple of people interested in a Balls Freedom Amp Preamp in a pedal if the good Dr wanted to build some...Would if I could, man!

The Freedom Preamp is different than just the preamp from the Freedom Amp, though. It's IC based.

Dr Tony Balls wrote:So I started to attempt a trace of one of these many years ago using gut shots found online. I didnt get very far at all before one of the old guys on the FSB forum posted the schematic. However, his web-hosting appears to be down so the schematic isnt around anymore and I dont think I ever printed out a hard copy. I'll try to dig around with the forum members there and see if anyone has it or knows what happened to the original poster.I bought one of these a while back and here is a selection of schematics I found online -- http://imgur.com/a/BkhL9The first appears to correspond most closely to the amp I have, though I've no idea how much it may have been worked on in the interim. Regardless, hope they help.

I reckon they'd be at least a couple of people interested in a Balls Freedom Amp Preamp in a pedal if the good Dr wanted to build some...

Evanc521 wrote:A few things:I don't understand the purpose of the voltage divider in the power supply... nothing appears to be connected to the half point.Ground (technically the zero-volt reference) is connected to the "half point." This effectively creates a +-4.5VDC bipolar supply for the 4558. Fairly common in pedal designs. The alternative is to bias the signal to +4.5VDC at the input of each opamp with a high-value resistor and run the opamp at 9VEvanc521 wrote:I'm sure there is a good reason for it, but I don't understand the purpose of the parallel resistors (circled in red). A non-standard value of approximately 27.7k must have been needed there. Nowadays, that value is readily available, but certainly wasn't in the 70s when this thing was designed. You could easily substitute if you have a 27.7k resistor sitting around.Evanc521 wrote:The volume control is fairly un-orthodox (circled in green)It's not a typical attenuator circuit. It's more of a variable gain circuit.Evanc521 wrote:Not sure of the value of the "mystery pot{ (circled in blue).It's serving a very similar function as the "volume" pot for the previous gain stage, but in a variable resistor configuration. A multi-turn 50k or 100k trimmer would probably be appropriate to dial in the desired amount of gain. For instance, you could set it to unity when "volume" is fully CW, though a few dB of boost would probably be more useful.

caset wrote:BTW, found this:http://www.freestompboxes.org/viewtopic.php?f=1&t=16394Looks like FM Dr Tony Balls is your man to talk to.Ah, I didn't see his name, I will get in touch with him.