Sola Sound - Tonebender MkIII

beedotman · Post by **beedotman** » 05 Sep 2011, 19:13

thanks!

Electric Warrior · Post by **Electric Warrior** » 05 Sep 2011, 21:19

Here's a schematic of the '72 to '76 version:

As I mentioned earlier, these came in a number of different enclosures. The most common variant is the silver and orange (or rarely yellow and black) "batman logo" Tone Bender enclosure. The Vox MKIII, Park Fuzz Sound, Carlsbro Fuzz and CSL Super Fuzz branded versions are not quite as common.

jimmybjj · Post by **jimmybjj** » 23 Sep 2011, 01:07

I made this layout to use some of my low gain transistors. I used a ge transistor for the diode on Q3. Don't forget the jumper next to the diode, or under if your using a transistor. On board charge pump so you can use your regular 9v adapters. I am 99.9% sure this is verified. I built one but had a error in the layout and i fixed it, and adjusted the layout, hence the jumper. Works well.

Layout Here

This board is in the style of John Lyons

bigmufffuzzwizz · Post by **bigmufffuzzwizz** » 24 Sep 2011, 01:10

Awesome layout Jimmy!
I learned so much just from this thread, falling into a fuzzz fever...

I've also been wanting to build a sili tonebender like the one on Basic Audios site for awhile now.

sinner · Post by **sinner** » 05 Jul 2012, 08:50

My bud asked me to do this, after hi scored one of these mkiii boards from Peps! (pigeon FX)

Two versions are attached
- ordinary mkiii
- 2knob fuzz sound mkiii

Just component names on PCB + matched component names on schematic. Use your favorite set - good source is this tread, or Fuzzcentral.

On my layout ins/outs are other (right) way around. In England even pedals are left side driven

Only PDF's

sinner · Post by **sinner** » 05 Jul 2012, 08:53

damn, mkiii ones again. accidentally I've uploaded 2knobers twice

beedotman · Post by **beedotman** » 05 Jul 2012, 20:39

Great work, Sinner!

sinner · Post by **sinner** » 03 Sep 2012, 19:03

I'm on it right now

I decide to test the dodes (1n34a) I've scored years ago from banzai music, and they all tests 0,62 to over 0,7vf, like the silicons... WTF? they should test half of that... Does it means I can't use that in mk3?

I can't find the rest of my diode stash

Electric Warrior · Post by **Electric Warrior** » 03 Sep 2012, 19:43

Just use a leaky germanium transistor.

sinner · Post by **sinner** » 03 Sep 2012, 19:54

was it collector (anode) an base?

I was able to find some black glass 1n60's with 0,3fv finally

Electric Warrior · Post by **Electric Warrior** » 03 Sep 2012, 22:00

Base and emitter. Not sure which is anode, but you'll know when it's wrong.

LucifersTrip · Post by **LucifersTrip** » 03 Sep 2012, 23:00

sinner wrote:was it collector (anode) an base?

I was able to find some black glass 1n60's with 0,3fv finally

that's funny...all my glass case 1N60's from the 1960's measure ~ .6v

LucifersTrip · Post by **LucifersTrip** » 03 Sep 2012, 23:11

Electric Warrior wrote:Base and emitter. Not sure which is anode, but you'll know when it's wrong.

you can use either base/emitter or base/collector

for pnp, emitter & collector are anode. base is cathode

for npn, base is anode. emitter & collector are cathode

funny, I just posted a pic of this on the DAM forum...my DOA bag of vintage transistors with too low gain, too high leakage, a short between lugs or a lug broken off...which I use for diodes

Electric Warrior · Post by **Electric Warrior** » 04 Sep 2012, 18:04

LucifersTrip wrote: you can use either base/emitter or base/collector

Yes, but base and emitter is what Sola Sound used.

sinner · Post by **sinner** » 04 Sep 2012, 18:42

I left 1N60 in, it tests right

Anyway, I'm stuck, as I have no any 20mm pots (omegs), as well as no styroflex caps of 220p/2n2 value

I decided to go with repro board from Brook this time, and with new production parts all the way - last time I was using new type of components was like 2 years ago

)))

So - orange Phillps caps (thanks B.man), and BC e-caps, and Dale CCF60 resistors (awesome resistors)

One resistor, the one between tone pot and volume was jumpered under the pot (common, anti-volume-drop mod)

transistors are the only NOS components, I've used Hitachi 2SB75's, not as fancy as some Mullards, but the gain/leakage buckets was what I was looking at

Two in darlington pair tests the same 55hfe/0,06leak, and 92hfe/0,19leak for Q3

I wanted to have leaky Q3 transistor as it's always sounds best to my ears if it's leaky, sometimes 1mega resistor between base and colletor helps if it's not...

Like I said, no pots right now, so I have to wait till they arrive

beedotman · Post by **beedotman** » 04 Sep 2012, 19:10

wow! sexy stuff!

Electric Warrior · Post by **Electric Warrior** » 04 Sep 2012, 19:55

76µA is leaky these days? What happened?

LucifersTrip · Post by **LucifersTrip** » 04 Sep 2012, 20:32

Electric Warrior wrote:76µA is leaky these days? What happened?

I assumed he gave leakage in mA, not voltage....so 190uA? which is still not really leaky. I used leakage ~250-300uA in similar circuits.

Electric Warrior · Post by **Electric Warrior** » 04 Sep 2012, 20:42

I assumed 0,19 would be the reading on a multimeter with an RG style hfe tester circuit.

sinner · Post by **sinner** » 04 Sep 2012, 20:50

peak dca55.

Imo 0,19 is planty for mk3, i can always short collector and base with an resistor

Sola Sound - Tonebender MkIII [schematic]