VanWhy
Well-known member
- Build Rating
I do love me a good MIAB. This is the newer one from Marshall.
Built to the BOM except I used JRC4559 for the opamps. Funny story, I purchased surface mount MC33178 but accidentally ordered the MOIC format instead of the SOIC. I got adapters but it was such a pain to solder such a tiny IC. Even with my most pencil-y tips it was rough. I did it though. But I auditioned the TL072, JRC4559, and the MC33178 and actually liked the 4559's best. Just a tad less noise but overall hard to tell the difference for all 3. Biggest difference I saw from the datasheet was slew rate.
Anyway, it does the Marshall thing. Not quite sure what the sensitivity knob is doing. The manual just says, "A second distortion circuit to access different JCM800 tones." Does sound good with it mostly maxed.
I like it. I think I've built 2 or 3 other JCM800's in a pedal types. This one is a solid contender in that field. My only nitpick is I'd like a little more volume. Which probably can be achieved by going with a larger value volume pot.
I've also done a bunch of those Marshall looking type designs (gold and black) so just wanted to do something different. Happy with the design.
The demo is just me testing it out after I finished boxing it up. Phone mic so nothing special. Certainly not pro. But gets the point across.
Built to the BOM except I used JRC4559 for the opamps. Funny story, I purchased surface mount MC33178 but accidentally ordered the MOIC format instead of the SOIC. I got adapters but it was such a pain to solder such a tiny IC. Even with my most pencil-y tips it was rough. I did it though. But I auditioned the TL072, JRC4559, and the MC33178 and actually liked the 4559's best. Just a tad less noise but overall hard to tell the difference for all 3. Biggest difference I saw from the datasheet was slew rate.
Anyway, it does the Marshall thing. Not quite sure what the sensitivity knob is doing. The manual just says, "A second distortion circuit to access different JCM800 tones." Does sound good with it mostly maxed.
I like it. I think I've built 2 or 3 other JCM800's in a pedal types. This one is a solid contender in that field. My only nitpick is I'd like a little more volume. Which probably can be achieved by going with a larger value volume pot.
I've also done a bunch of those Marshall looking type designs (gold and black) so just wanted to do something different. Happy with the design.
The demo is just me testing it out after I finished boxing it up. Phone mic so nothing special. Certainly not pro. But gets the point across.
