Boogie Monster / Dr Boogie

owlexifry

New member
4th pedal build.

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used SMD MMBFJ201s with adapter boards.

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no issues getting it to work.
appears to operate is it’s meant to.

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spent a while dialing different bias settings on the trimmers.

no matter how it’s set, it sounds terrible, tinny, and thin. no balls, no richness.

just sounds like a cheap terrible distortion pedal :/
im wondering what i’ve done wrong, as a lot of people seem to dig this pedal design.

i even built a charge pump to run it at 33V in the hopes of improving headroom.

this didn’t change much, just made it a bit louder / brighter.

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i dunno, maybe it’s my ears being used to very good sounding high gain tube amps (peavey 6534+, SLO, 2204/jcm800 hot rod), and perhaps no solid state preamp pedal is gonna sound any good to me...

or perhaps i just overheated the J201 JFETs and should try another lot?

maybe i should try 2N5457 JFETs instead?
 

BuddytheReow

Well-known member
Try the 2n5457s. They're similar but not identical. Trying to mimic a high end tube amp with solid state parts will be a challenge in general since they behave differently (correct me if i'm wrong here).
 

Betty Wont

Well-known member
What are your FETs biased to? with j201 I like to start with q1 ~6v and the rest to ~5v. The boogie is a pretty sweet high gain preamp, though I do find it lacking a bit in the bass range.
 

fig

Well-known member
What are your FETs biased to? with j201 I like to start with q1 ~6v and the rest to ~5v. The boogie is a pretty sweet high gain preamp, though I do find it lacking a bit in the bass range.
Yeah..at first It seemed more flat but with different scenarios it is more like a shallow bottom. Thanks!
 

owlexifry

New member
Try the 2n5457s. They're similar but not identical. Trying to mimic a high end tube amp with solid state parts will be a challenge in general since they behave differently (correct me if i'm wrong here).
I reckon i will, might even try MPF102 as well.

What are your FETs biased to? with j201 I like to start with q1 ~6v and the rest to ~5v. The boogie is a pretty sweet high gain preamp, though I do find it lacking a bit in the bass range.

I've tried a bucketload of different bias settings/combos. I've probably tried the arrangement you've suggested. No matter what I do, nothing really sounds that great.
Maybe I'm just expecting too much from this, maybe the demo videos i watched/heard that caught my interest are too forgiving, and actually hearing it in the flesh is an entirely different thing, which we know applies to all sorts of gear.

I just cant believe how thin it is. There's zero bottom end happening. The contrast between 'clean' (pedal off) and pedal on, is like turning the bass knob all the way down on an amp. actually, it's worse than that.

I'll look for my notes, but I modified quite a few values especially for more bass. Lots of suggestions if you Google it. Mines not perfect but much better than stock.

Would be super keen to try out these mods. Please post these up if you can find the notes. Many thanks.
 
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gaffled

New member
I couldn't find my list of mods so I'm not sure what resistors I changed but I opened the pedal and was able look at the caps I changed.
C3: 4.7n
C11: 10n
C12: 47n
C15: 680n
C16: 4.7n
C17: 68n

I'll keep looking for my schematic as there were a couple of resistor changes.
 
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