Tonebender Mk1 Transistor sets at now at SmallBear

I played with the input and output capacitors and while they did make some interesting changes, it wasn't quite what I was after.

Then I switched Q2 and Q3 transistors and there it was. The bass was reduced enough that the mids and treble could shine through. The fartiness is less and the attack knob is more useful through most of the sweep. So now I can take out the sockets and solder in the stock capacitor and transistor values. I think I will keep the transistors socketed so I can switch Q2 and Q3 back if I want the bassy fartiness back.

Thank you all for all of your help. So glad I attempted this notoriously difficult pedal.
 
I played with the input and output capacitors and while they did make some interesting changes, it wasn't quite what I was after.

Then I switched Q2 and Q3 transistors and there it was. The bass was reduced enough that the mids and treble could shine through. The fartiness is less and the attack knob is more useful through most of the sweep. So now I can take out the sockets and solder in the stock capacitor and transistor values. I think I will keep the transistors socketed so I can switch Q2 and Q3 back if I want the bassy fartiness back.

Thank you all for all of your help. So glad I attempted this notoriously difficult pedal.
Use a log pot if you want more variation across the Attack sweep
 
I got my Small Bear MKI set in the mail this week and set it up on the breadboard yesterday. It sounds pretty good right out of the box with standard component values, didn't really have to do anything to get it to work. I'll be tweaking a little to tune it up but it already sounds decent. The set is a little pricey, but the selection they put together for me works well.
 
I got my Small Bear MKI set in the mail this week and set it up on the breadboard yesterday. It sounds pretty good right out of the box with standard component values, didn't really have to do anything to get it to work. I'll be tweaking a little to tune it up but it already sounds decent. The set is a little pricey, but the selection they put together for me works well.
Great! What hFE and leakage did they send you?
 
if I'm reading the labels correctly Q1 is an OC75 with hFE 75 & 250(?) leakage, Q2 is a CV7003 with hFE 131 & 40 leakage, Q3 is an OC42 with hFE 100 & 15 leakage.
 
I messed around with a few part substitutions but honestly it sounds pretty decent with stock values. I went with 470k on R3, 33k on R10, and 1.8M on R9 of Andy's schematic https://vero-p2p.blogspot.com/2022/12/tone-bender-mki-component-values-table.html
I've never seen that page, I wonder how that info was obtained, it's gold! Your circuit sounds greta. How's the range on the Attack knob? With a linear pot, mine practically did nothing, which seems in line with demos I've heard. I changed it to a log taper and now it's more useful to me.

I'm definitely going to try the Gary Hurst version with the 2 extra resistors and try all the various versions. Thanks!
 
My range on the Attack knob is not very wide, maybe I should try a linear pot. I tried out a 25u cap after Q2 like the Gary Hurst version but preferred a 100n. My old MKI build is a Gary Hurst version with 2 25u's, I might swap out that 2nd cap on that one too. Andy's blog has a lot of good stuff on there, definitely worth a look.
 
I've never seen that page, I wonder how that info was obtained, it's gold!

It was obtained by a lot of digging around of old posts and looking at photos. Glad you like it - the blog started as a reference for me (and still is), I perhaps got a little carried away with the scale of it. 😁 I happen to have a couple of MKIs on the bench at the moment myself. Always fun to play with.
 
It was obtained by a lot of digging around of old posts and looking at photos. Glad you like it - the blog started as a reference for me (and still is), I perhaps got a little carried away with the scale of it. 😁 I happen to have a couple of MKIs on the bench at the moment myself. Always fun to play with.
All those precious secrets out in the open...watch your back 🤣
 
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