Amentum boost potential mods


Active member
I built one of these a few months ago and while I like it, sometimes the EQing it does is a bit extreme for my taste. I used 2N5088 instead of the 2N5089 as from what I read the two are fairly similar. Is there a simple mod or transistor swap that may tame some of the harshness this pedal gives me?

Feral Feline

Well-known member
Datasheet is shared by the 5088 and 5089. From what I can decipher and recall having read... the 5089 has a wee bit more hFE, but also has slightly better SNR.

I'd try to determine exactly when it's harsh-sounding ie with what other pedals is it exhibiting that harshness?
You could try a lower-gain transistor so it's not driving the other pedals as hard, but if it's the Amentum itself, then a lower gain transistor would just go into saturation even sooner — so maybe try a 2N5089 for that wee bit more headroom?

Try lowering the gain of the circuit by raising R2 (1k3) to 1k5, 1k6, 1k8...

Just thinking aloud, wish I could be of more help.


Just built this. Simple, tiny, cheap and easy to build. No reflection on PPCB, but man, I agree this circuit it's H-A-R-S-H-spells-harsh sounding and not too useful in my rig. It's got a "distinct character" (like saying an ugly girl has a "nice personality"). It benefits the neck humbucker I guess, so maybe you need it for that? My $.02 is if you want something "Treble Booster-ish" consider the Naga Viper (Dragons Breath) and if it's full-range, one-knob boost you're after then the Cleaver (Katana) is so sweet.


Well-known member
I haven't played with mine in a long time, but I need to try it out again. I play bass and remember it being actually kind of a mellow boost which is why I haven't played around with it much. I'll have to break it out again soon to see if I'm just misremembering.

I can't stop singing the praises of the Mercurial Boost (Varioboost). Its a simple build and is a tone monster. Worth doing some research on at least.
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Dr. Satan

New member
Increase the value of the coupling caps (C2, C3) to allow more than just treble frequencies through. You'll get more noticeable difference from the output cap but the input cap will have effect too. It's no different than modding a treble booster, because it is a treble booster.


Active member
the Varioboost looks super cool

I do want something that isn't a super transparent boost so I do like the concept of the Arrows, it just goes a bit too far for me, I'm going to build another one and socket the caps to mess with them, otherwise I might build the Varioboost


Active member
FYI I built another one of these, waiting on some capacitor values to fully optimize it for my taste, however my first impression is that this one is a little less harsh. My last build used a 2N5088 and some cheap caps, this one uses 2N5089 and better parts if it matters or maybe its a placebo

I tried changing C3 from 10n to 22n and it gave a very full sounding boost so I think C3 somewhere in-between those two is where I will end up


Active member
last update, I tried changing both of the caps but as of now I left it stock since I think it sounds pretty good

it also sounds good switching the values of C2 and C3