Mesa Boogie Tone Burst

turbofeedus · Post by **turbofeedus** » 26 Sep 2020, 04:17

I played one of these in GC and remember thinking it was pretty alright.
I found one cheapish on ebay so I figured I'd trace it.
Enjoy!
P.S. I'm new to eagle, if anyone can help me export the schem to a scalable format I'd reupload.

HamishR · Post by **HamishR** » 26 Sep 2020, 05:48

Thanks for tracing! It looks a lot like a mash-up of Xotic AC/RC Boosters with a hint of BB. I wonder why they felt the need for two ICs? Surely this could be done with one.

HamishR · Post by **HamishR** » 26 Sep 2020, 07:09

Just a query - Looking at U1B are you sure R4 goes to Pin 6 and not Pin 5? I had a feeling it should go to Pin 5 but I may well be way off course!

Thanks!

turbofeedus · Post by **turbofeedus** » 26 Sep 2020, 12:35

HamishR wrote: ↑26 Sep 2020, 07:09 Just a query - Looking at U1B are you sure R4 goes to Pin 6 and not Pin 5? I had a feeling it should go to Pin 5 but I may well be way off course!

Thanks!

Yep, had to double check that stage myself. The schem is correct.

HamishR · Post by **HamishR** » 26 Sep 2020, 16:58

Cool - thanks! Just drawing up a Vero layout. Might be worth a build...

HamishR · Post by **HamishR** » 28 Sep 2020, 04:31

Not verified yet but it should work. I hope! I changed the diode arrangement a little but that would be easy to change back to original. It shouldn't make a huge difference either way.

Petrvm · Post by **Petrvm** » 29 Apr 2021, 21:07

Hello everybody! First time here and first time trying to fix a pedal... So I found that I have a fault power supply that one day as make a weird noise and since then my Mesa Boogie Tone Burst doesn’t have the same sound. Just open the pedal and find a capacitor in short circuit. Is the “C8”. Can someone help me, where can I find one to replace it? What is the type and the reference of the Cap? Thank you!

arivabox · Post by **arivabox** » 29 Apr 2021, 23:29

Petrvm wrote: ↑29 Apr 2021, 21:07 Hello everybody! First time here and first time trying to fix a pedal... So I found that I have a fault power supply that one day as make a weird noise and since then my Mesa Boogie Tone Burst doesn’t have the same sound. Just open the pedal and find a capacitor in short circuit. Is the “C8”. Can someone help me, where can I find one to replace it? What is the type and the reference of the Cap? Thank you!

Capacitor 33n (0.033uf) 100v

Petrvm · Post by **Petrvm** » 30 Apr 2021, 08:58

Thank you a lot!

drocelot · Post by **drocelot** » 28 May 2021, 06:05

HamishR wrote: ↑26 Sep 2020, 05:48 Thanks for tracing! It looks a lot like a mash-up of Xotic AC/RC Boosters with a hint of BB. I wonder why they felt the need for two ICs? Surely this could be done with one.

They are using them as buffers

Ichabod_Crane · Post by **Ichabod_Crane** » 28 May 2021, 08:15

I tried to trace (not to build) the veroboard layout. It's seems ok, but it has some minor difference with the schematic above.
The 47pF should be 51pf, but it doesn't matter too much.
The diodes are two pair of three 1N4148 in series, if you don't care to solder the diodes stand up I think it's easy to change it. (As Hamis said).
In the power supply there's a different approach to polarity reverse protection, but this doesn't matter too much, because it have no effect to the sound.