Hello

This is a nice and rare rack mount tube preamp from the early 90's from Jackson. I have traced the power supply and created a schematic. Its just a simple linear supply.
I was thinking about reverse engineering the whole thing. Leave a comment if you want me to trace the entire thing. If I get enough interest Ill do it.

I posted a YouTube video about it on my channel:

JacksonJX3_PowerSupply.jpg

Peace out.
Pete

INTRO
Hello everyone. The Blues Driver always pops up among the most popular overdrive pedals, no doubt because many people like how it sounds, but also because it's easy to find and relatively affordable, being from one the biggest pedal company in the world. It's not as popular in the DIY world, aside from mods, probably because it's not the smallest circuit and uses many transistors in a discrete op-amp configuration. Also since you can get it anywhere for cheap, I guess most people just...

hello guys!

i built one and sounds pretty good but there is not enough gain.... i measured the resistance across the gain pot and it shows around 45K (some parallel resistance?), after that i disconnected the gain pot entirely and measured the resistance between IC pin1 and pin2 with the same reading....what could be wrong here.....
Thanks in advance

I've played these a few times and always liked them.
The usability is insanely bad, you have to have fairy fingers with the stock knobs in order to use the second gain knob. The stompswitches are way to close together.
Anyway, I found one used and picked it up. Was surprised to find mostly through hole components, and pretty well made. Not surprised at all to find a sanded IC. :roll:
I started to trace and to be honest with y'all, I got bored. I did find a few discrepancies with the RC...

Hey guys,

I need some help with biasing the transistors in this Build the Wolfgang 61. I adjusted the drain voltage to around 4,4-4,5V expect for Q11 because I only have a range of 9-6,5V? I’ve got some sound out of it but the volume was so low I had to crank the volume of my 120w stereo combo to like 7-8 to be able to hear it very quietly when I wanted to increase like postgain r for example it started to make weird sounds and would get loud as fuck also there wasn’t any real fx applied to...

Hi guys,
I was just reading a lot of topics and I'm looking for clues to repair my EHX Memory Boy.
It was stored for some years, and now i can't get any effect out of the pedal, i already tried battery, and AC, and the behavior its the same, i can turn it on and off, i have sound, but no effect...
Delay and Depht doesn't affect the sound and blend and feedback just do some type off modulation turning the sound imperceptible.

Anyone can help me with this one?

I've been hunting down this pedal for a while after EQD featured it on their youtube channel.
This is second version, 350 made for prymaxe. There is a V1 of which only ~20 were made.

zapmachinev2.jpg

PCBtoptraces.jpg

PCBbottraces.jpg

Here is my guess for V1 based on the screenshot below from that youtube video. THIS IS AN APPROXIMATION, USE WITH CAUTION.
Specifically, I'm not sure about the emitter connection for Q2, either the 1K or 470R might be an emitter resistor....

Hi, gang! Here are some gut shots of my Memphis Tremolo modulator, and also an x-ray component side shot of the PCB showing parts & placement. I have seen gut shots of many other Memphis pedals online that use the exact same PCB! VERY clever engineering! I had originally intended to draw up a schematic also, but I'm too lazy to do that by hand anymore. Perhaps a group member might suggest an intuitive (like: drag and drop schematic symbols from a list) program for drawing schematics?

pls delete

Hey - I had some time between jobs to kill, and after building several circuits from PedalPCB I've started learning PCB design with KICAD by building open-source versions of classic effect circuits. I'm trying to get one put together a week, focusing on classic drive and fuzz circuits with only minor modifications while breadboarding (with some luck, the pace will slow down again once my day job starts up again). I thought I'd share what I've gotten up to so far in case it's interesting to...

Speaker Line Out Isolation Transformer question:

Does anybody know what Type/Spec ‘Isolation Transformer’ Suhr or Bradshaw uses for their Speaker Line Out Boxes? Correct resistances?

Want to attempt to make one.

I see these resistance specs options but don’t know what is needed:
— 600:600
— 10k:10k
— 10k:600 ?

— Xicon, Jenson, Edcor ?

Anybody have any ideas or knowledge on this?

Thanks for any help

The Sonicake Volwah is an extremely affordable, real estate saver of a pedal, with volume and cry baby wah style combined into one tiny enclosure. It has two LEDs which seem to be RGB to me since they are green when Volume mode is active, and red when Wah is active.

Without questioning it's build or sound quality, my main issue with it is that the LEDs are UNDERNEATH the expression surface. This pedal really small so you can't see it entirely when it's under your foot and that's just part of...

Good afternoon,

I was modding an unrelated Bad Monkey overdrive and one of the mods adjusted the intensity of the bass knob. I reverted it because it was too much for my liking, but it worked really well into my DS-1.

My question is, are there any ways to add a pre-distortion bass boost on the pedal? Hopefully one that wouldn't require I add my own little circuit board into the pedal?

Yet another one bugg has posted on his site:

Box of Rock variant, with minor changes to cap values Q2/3 source resistors and D-G bias resistor of Q3 so would be quite possible to do a BoR/'59 Sound mode switch with a 4P3T rotary.

I like this more than i remember liking the BoR when i made one years ago, but i just don't like having a single BMP style tilt tone pot and am considering putting a Bassman tonestack on the end instead - If anyone has any advice/suggestions/experience of doing...

Thought I'd pick up one of these to see what it's like.
I was hoping I'd be lucky and it would be a take on the Moen Shaky Jimi/Jimi Nova, which are based on the EasyVibe.
Here's links to the Moen Shaky Jimi and Moen Jimi Nova threads.
And I'd like to thank John Hollis for his lovely EasyVibe circuit. :thumbsup

What's inside then? The highlights:
1 x ST 064C
3 x TI TL062C
4 x LED/LDR pairs

It does indeed look to be generally based on the Moen/EasyVibe circuit although I haven't checked the...

Would anyone have a schematic or service notes for the Boss DD-6.
I bought one over the weekend. Totally dead as described.
No light or sound at all.

Hoping it's just a power problem. Found a post on another forum that suggests it could be the IC6 5v regulator. Will check that first. As well as checking all the power rails are correct.

There are some similarities to the dd7 but feel like im flying on the dark without a schematic.
Can find the dd3, 5 and 7 but not 6.
Does anyone have it?

I found a video with a few pics of the PCB and managed to trace cabinet sim section.

When I compare the frequency response of the circuit as drawn it doesn't seem to match up with the response plots of the GI100 I've seen. It's not bad but it looks a little bottom heavy and the mid dip frequency looks a little high. Having said that the impulse responses I've seen all seem to disagree in the low end. I don't know what to believe.

I'm sure the part values that matter are correct on the...

Hello
Since high beta germaniums become so expensive Im searching for germanium transistors with low hfe and leakage. Do any of you know what russian models to search for??

Like like 1-10 hfe maybe at most 20
And 1-30ua leakage, the lower the better

Its for distortion pedals and the low leakage is the most critical since i use them in darlington configuration

I”’ve hade excellent results with af239 and a few other low leakage AFs with zero to 20ua leakage.

Sorry for my bad english

bonson.PNG

Hello, this is a circuit based on the Benson Preamp, called the Bonson praemp, because I'm refusing to call it a preamplifier. This is part of a streak of me going through circuits I see and even like, to conform them more to my standards while trying to keep the same timbre and character. A more thorough explanation is give at the beginning of the Clown thread .

Up for some circuit analysis? The Bonchild (name changes every time, it's a rule) consists of the same building block...