The two schematics are identical regarding the diodes. Two ways of drawing the same thing, switching diodes between feedback loop and output of the opamp to ref/VB. When the diodes are in the feedback loop there is a difference: PedalPCB shorts C14, R15. Only 1k (R9) between opamp and tone control....

Hi Guys, yesterday a frind of mine give me a Darkglass Duality to try. I just opened it and shoot some pictures. It is based on 4049UBE CMOS. All Pots are 100kB except for the Level Pot which is 100kA. unfortunately I cannot hold the pedal so I will start tracing the pedal from the photos. In the ne...

Somebody knows which HFE is used for the 2n1306 in the original amp? I'd like to replicate that sound.

I solved the problem changing the blend control design. I used a differential amp as blend using inverting section for fuzz and non inverting section for the clean signal.

Ok this morning I checked again the images and I found I made a mistake: I inverted R19 and R20 connections. I confirm it is a James filter with "treble" section fixed. I will update the schematics this evening!
Maybe this schematic is the same of 4 band Eq of the B7K and Vintage deluxe.

Dear all, I'm interested to the Tech21 British Schematics but I can't find the thread.
Somebody can uplad it again or send me a PM with the latest scematics?

Thanks Jim, this evening I'll add resistor value and I'll try to check capacitor value.
Today I want to check some link.
I don't know why R20 is connected in that way. I've seen always configuration with lug 3 of pot connected with the output of the Op Amp.
Somebay can explain me this thing?

here you can find more photos:
https://www.dropbox.com/sh/drzjh8ogp3fc ... jP4Ka?dl=0

Photos are 20M so you can enlarge and see every part. Please write me if you need some continuity test.

IC: MC33179DG
Potentiometer: 50k
R12 connected to Pin6 and Pin 8 of U1

Dear all,
A friend of mine have a Darkglass Tone Capsule. Actually he send me a photo of the device.
I asked more Photos with more details.
Somebody is interested to help me to tracing this electronic?

Already done.
I'm thinking this pickup is too hot... How can I reduce the input of the lm4250?

Dear all, I built this preamp for my musicman and I found it awesome on my stingray. After that a friend of mine ask me to build another one for his eko mm300. After wired it I found that it's distort a little bit. Can the eko's pickup cause the lm4250 distortion? This pickup has 4 cables and I wire...

I'm trying to rebuild the fuzz section of this amp. It is normal for this circuit to reverse the phase? Based on this schematic, you can see that clean section is reversed compared to both original signal and clipped one [ Image ] I used the original acoustic 360 schematic to build my version not t...

I'm trying to rebuild the fuzz section of this amp. It is normal for this circuit to reverse the phase?

Here you can find the list of components and some photos.

https://www.dropbox.com/sh/nv3c0h48qq6u ... 6pLfa?dl=0

How I can find the value of smd capacitor?

I have the punch version but I'd like to try also the thump version.
where I can found the schematics?

Hi guys,
does anyone have the schematic of hot rod plexi? I have it in test for days and I really like it.
I can send you some photos of the board.

Somebody tried to run it with 18V? It works better than 9v?

ok I reversed the treble and bass potentiometer. now it's work. I really love it!

Hi guys,
I finished this preamp now and I mounted it in my MM Stingray.
It work well but when the bass potentiometer is at maximum it's doesn't sound.
What could it be?

After using the audio probe I found a little bit of fuzzed signal in the input point so I suggest I have a bad ground.
I found another issue: with gate pot at 0 and drive at max the pedal whistle a lot.
I'm a noob so somebody can help me to solve these problem?