Last Breadboard of 2022: The Timbre Man

[Chuck D. Bones]

James (HamishR) sent me a schematic of a Vemuran TSV-808 he had modified. I did my thing with it and came up with this. It's pretty close to a Timmy III. The only short-coming of the Timmy (IMHO) was the weak midrange when TREBLE was dialed-down. I reconfigured the last stage to resemble the mid boost stage in the Friedman Brown Betty. It doesn't take much boost to bring the mids back to life. The MID control could be an internal trimpot or hard-wired for a 3dB boost. D5 adds a smidge of asymmetry to thicken up the sound bit. R8 & R9 are there to smooth out the taper of the DRIVE & TREBLE pots, respectively. Like the Timmy, it's a "transparent" low-mid gain OD. If you want more sustain, you can use it to push another dirt pedal. Or get crazy with C3 & R4. All component values are negotiable. You can try different opamps if you're like that. I recommend tantalum for C11, film or silver mica for every other cap except C10. Any Ge diode will work for D5; leakage is not a concern.

 

[Fingolfen]

I know this is a fairly trivial question, but why a 10K LED resistor? Is this not a 9V in, or is it a 9-18V?

 

[Chuck D. Bones]

Here's the trivial answer:
It depends on the LED. I have some Agilent aqua LEDs that are way too bright with a 10K ballast resistor. I have some plain old red LEDs that are too dim with 10K. It's dealer's choice.

 

[Fingolfen]

Here's the trivial answer:
It depends on the LED. I have some Agilent aqua LEDs that are way too bright with a 10K ballast resistor. I have some plain old red LEDs that are too dim with 10K. It's dealer's choice.

Gotcha - I even have some ex-Soviet LED's that I think I could almost jumper and they'd be dim... of course, they'd likely burn out too... *lol*

 

[HamishR]

So still using the 1K at R5? Swapping it to 4K7 made the world of difference to mine - although I'm using a B taper bass pot.

I drew up a Vero layout if anyone is interested.

 

[BuddytheReow]

Breadboard pic or it doesn’t count . This is on my list to try

 

[HamishR]

 

[Chuck D. Bones]

I think the lineage goes like this:
Timmy III -> TSV808 -> Timbre Man -> Timbre Man cb mod
By the time I was done sifting out the chaff, there was very little of the TSV808 left. Compare schematics and you'll see what I mean. My mods were not about "improving" the TSV808; they were about tweaking the Timbre Man.

With a B50K BASS pot, you're pretty much committed to having at least 4.7K for R5. C50K and R5 = 1K gets me another 2dB gain at 100Hz and 3.5dB at 300Hz for a fatter sound when I want it. C-taper provides a much more even sweep across the dial in this type of circuit. Either configuration works, it's all about how much bass you want. For more deep bass, increase C4 to 1uF.

gray: B50K + 4.7K at zero
pink: C50K + 1K at zero
turquoise: B50K + 4.7K at noon
red: C50K + 1K at noon
blue: B50K + 4.7K dimed
green: C50K + 1K dimed

These curves were run with DRIVE dimed. Stage1 is pin 7 of the opamp. The freq response at the output will look the same when MID is at zero and TREBLE is dimed.

 

[HamishR]

Wow - that's really interesting! I'll experiment some more with the bass pot taper. Right now the B50K with R5 as 4K7 is working well and I get as much low end as I could need.

I think the real magic of this particular Timmy variant is the midrange. It's in just the right place. It's still the "transparent" OD everybody loves the Timmy for but as you raise the gain it imparts some character to the sound, which really is what I want an OD to do. With gain very low you can get it to sound much like the bypassed signal (pointless but "transparent"). As you raise the gain you get the beautiful vocal mids perhaps better than any other low-gain OD I've tried. And with a crisp clear low end and not too sharp highs if that's what you want (yes please!).

 

[Chuck D. Bones]

If your favorite setting is noon, then I'd leave the BASS pot as-is. Changing to C-taper will move everything in the CCW direction.

 

[HamishR]

If anyone is curious, I can vouch that the layout above works. I just built it and it's very cool if I say so myself - the midrange control is killer - it works independently of the bass and treble and at noon is much the the sound you will get without a mid range pot. So it's well voiced in that regard. Boosting it lends some extra punch, reducing it is interesting but I would generally leave it at around noon unless I was using a BF Fender or something similar I guess. It is fun to boost the mids though. Fab to have such control.

 

[perfboarder]

quick draw for perf. After finish, realized this circuit use C pots. Oh man, hard to get locally here.

 

[Chuck D. Bones]

Given that there's not much going on below noon on the MID control, one could change MID to B50K and put a 39K in series with pin 1. Friedman uses C100K for the MID pot in their pedals.

Here's your breadboard pic, Sandy.

 

[Chuck D. Bones]

Stick a fork in it, it's done. The MID pot now goes from about +3dB to about +9dB at 700Hz. Added R12, changed R10, VR3 and C7.

 

[MattG]

I just now submitted an order for a PCB I whipped up for this circuit. I interpreted the description as "Timmy with a mid boost" - is that fair? I've long thought that concept would make for a killer do-it-all type pedal, as to me, the Timmy is what I think of when I hear the word "transparent". And transparent is wonderful if you have control over the whole tone stack, from guitar to amp, and everything in-between. But, especially with amps, sometimes you find yourself playing through some random amp with a very different EQ than what you've built your pedal board around. It seems like if the Timmy had some way of manipulating the mids, it's hard to imagine a scenario where it wouldn't work... At least that's the thought process that got me excited about this Timbre Man!

 

[Chuck D. Bones]

Pretty accurate description.

Cork-sniffers might want to try OPA2134 in place of TL072.

 

[KR Sound]

I just now submitted an order for a PCB I whipped up for this circuit. I interpreted the description as "Timmy with a mid boost" - is that fair? I've long thought that concept would make for a killer do-it-all type pedal, as to me, the Timmy is what I think of when I hear the word "transparent". And transparent is wonderful if you have control over the whole tone stack, from guitar to amp, and everything in-between. But, especially with amps, sometimes you find yourself playing through some random amp with a very different EQ than what you've built your pedal board around. It seems like if the Timmy had some way of manipulating the mids, it's hard to imagine a scenario where it wouldn't work... At least that's the thought process that got me excited about this Timbre Man!

Awesome. I wouldn’t mind checking that out, too.

 

[MattG]

I received the PCBs on Friday, so built up the prototype this weekend. It worked on first power-up, though I suspect I made a mistake somewhere. Obvious mistakes are the treble and mid pots being wired backwards. But, how much gain (distortion) does this drive have? The drive knob needs to be around noon before there is any noticeable breakup, and even with the drive maxed, it's still a very light drive. Is that the design intent, or did I make more subtle mistakes?

 

[Chuck D. Bones]

Let's see your schematic. In the meantime, recheck your build, make sure you didn't get a wrong part in there somewhere. This thing is not a gain monster. Check the freq response plot I posted on Jan 1st. The gain peaks at 40dB. Compare that to a FuzzFace that peaks in the 70dB range and BMP that gets up into the 80's. We can make more gain if you want it, but first let's make sure it's built per my schematic. Which guitar and pickups are you using?

 

[MattG]

Here we go, a few notes:

• As previously mentioned, the mid and treble pots are wired backwards (an inconsistent nod to the original Timmys, where bass and treble knobs were cut!)
• Checking just now, I realized I left out R10 (27k, part of mid control)
• For the actual effect circuit, I used the same references as Chuck
• I only took a couple liberties: added an extra 100nF to the power supply; and I changed C7 to a pair of caps in parallel (because I had 10nF and 2n2 caps in my inventory, but not a 12nF)
• I also integrated the ne555 simple relay bypass

I'll see if I can hack that 27k into my prototype build.