Traced from a 2004 unit.

Clearly based on a tube screamer with some interesting addtions/changes. With my set up the Phat switch doesn't do much.

There is no pull down resistors. The Bias rail isn't at half the supply. The last half of the 2nd op-amp is not used.

I can't add the schematic so here is a link to my reddit post with it attached.

Hi,

I bought a broken RV-5 because I thought I could repair it. First thing I noticed is that somebody tried to replace the D1 with another non SMD diode, but I quickly replaced it with the original part. By then, I had noticed the IC6 S8520E33 was hot, so I did the 3v3 stabilization mods, except that I used a LD1117V33 with a TO 220 package (I checked and it seems to be the same as the other one; I couldn't find the SOT 223 package anywhere where I live). I soldered the 1117 with little wires...

Hello. I wanted to create a preamp on field-effect transistors so that I could connect various overdrives and fuzzes to it.
It turned out something like this:

To get 30V I used a module on XL6009. For now, this is an intermediate version, because I plan to try it with a bass guitar and, perhaps, some other moments.

Breadboarded and seems to work:

SIM

Press and hold the switch to reset, ramp up, and finally hold the control voltage. Higher CV=longer delay. Some of the values are altered to make it look better in the sim. More appropriate values shown in the image below. I have them this way in the sim because it's dreadfully slow to watch the circuit operation at normal speeds.

There are plenty of other ways of doing this, sure... but there's something satisfying about using the PT2399 itself to...

I've been on a quest to make a distortion pedal that suits the instruments I have and my playing style and so far I like this one the most. I'd been playing with non-inverting soft clip type of circuits (e.g. Tube Screamer) and didn't hate them, but when I tried stacking a boost in front I got an unexpected result - instead of more saturation I got more clean blended in with the signal. That might work for some people but it's not what I was going for.

So I switched to an inverting...

Hi all,

My first try at tracing a circuit and third layout.
The circuit has an input + buffered output and an xlr ofc.
Versatile as it can be powered 9-16VDC or by phantom power.

The layout is verified , as I built it a few hours ago and works perfectly !

Peavey-EDB1-schematic.png

Row H can be ommited as it is not connected to any component.

Peavey-EDB1-layout.jpg

Cheers !

Hello, Is there anyone who has the Keeley Compressor Pro and can send me high-quality and high-resolution photos of its PCB ? I want to design a compressor with THAT4320 and I want to get help from this pedal. :D

Guys, help me,
I got this pedal dismounted who knows why, i did that long ago.
I remember to like this effect, so i want it to try it one more time.
The pcb board is ok but there is no 3dpt switch connected to the main board, i now have this six pins which i have no idea how to connect. I just want it to hear it again and if i likex it, i will buy a new 3dpt switch and install it.
IMG_0953.jpeg
As you can see i have already tried to make it work and understand how the six pins are connected...

A lot of people really like the old Rockman modules. They have been out of production for a long time now yet there are no schematics available. I understand the US patents expire after 20 years so they would not now be covered (?). Looking at pictures of the stereo chorus pcbs, it looks like it would be possible to clone it and I would love to have a go but without an accurate schematic it would be a world of pain. Has anybody else tried this?

Hello guys! 😄
I found this pedal sitting around in my drawer, something I got a while back from a friend who told me it was some kind of overdrive.

The pedal came with one knob missing and no labels at all. I tried to figure out what the knobs do and wrote down some labels I applied, but honestly, I’m not sure if I got everything right since I’m kind of a noob with this stuff...

Could someone help me figure out if my guesses are correct? In particular, I’m really curious about what the two...

Hi,

I have got a 720 EHX Looper, which makes a whining square wave tone above 10khz when used in half speed playback mode.

Any Idea what it might be? Or how to troubleshoot it.

Ok, I might intentionally have double posted this :D. I do apologise, but I think this might be of interest to more people.

I have some Qtron (+) mod questions:

1. Volume mod. I presume it would be done by adding a A10k in a standard way like this?

2. R32 mod. Is it the R32 as in the schematic of this thread ? And with what should it be replaced? I think it is already altered in this version as I read it was replacing the 100k with a 47k or lower. Am I correct?
3. Mix mod. Am I correct in...

This is the most recent refinement of a generic boost/buffer circuit I've been using for a while. It's a soft clipping boost with a subtle crunch, like a perfectly toasted bagel. Bypass scheme inspired by Valve Wizard , diodes-to-ground soft clipping inspired by Thunderbird (and discussed in this thread ).

I used a 10k linear pot but a different taper (log or audio I suppose) would let you omit R6.
My schematic says opamp_quad but feel free to ignore that and use a TL071 or similar.
D5/D6...

Hi to all.
Fuzzface has undergone so many modifications, so only mine is missing :D
I set out to redo the fuzzface in a way that would be easy to repeat and not sound as sharp as the silicon transistors. Therefore, I decided to add zener diodes between the base and the collector and it softened the sound. Also, the capacitor at the input is also of reduced capacity so that there is no excess of low frequencies.
Here is the modification scheme:

And here is the video:

Criticism and...

Hi all!

I have been doing some research upon this issue.

I recently got an old V2 EHX Small stone in that didn't work. In the end I traced the problem to a non functioning EH1048 IC in the LFO section. I replaced that IC with a socket.
- With a spare EH1048 I got from another pedal I get a fine working EHX Small Stone
- With a CA3094 I don't get any working sounds

In all the schematics and information online I can find that everybody mentions that the EH1048 is a rebranded CA3094.

Guess...

I got this unit in as it wasn't functioning correctly. I tried part of the problem to a wrong oriented filter cap. When I measured most electrolyte caps I noticed that they didn't measure properly. In the end I replaced all electrolyte caps.

Belcat - Power Master.JPG

Notice that all voltages (after the fix) are of different values. Guess a low quality pedal!

Check my blog for some pics