SOLA SOUND: Tone Bender MK1.75 ‘El Diablo’

The El Diablo…   A Dave Main creation, part Sola Sound MK1.5 Tone Bender / part Vox Tone Bender – hence the MK1.75 moniker.  And why El Diablo? apart from the colour, this thing sounds mean as hell.

They appeared to use a couple of different transistors for Q2, but the OC75 remains up front – the OC75 definitely provides a sonic signature in a circuit like this.  The version I saw with the OC84 transistor has a small silva-mica cap between the collector and base of Q1 (I couldn’t see the value).  

From the Vox: 

  • smaller input cap
  • smaller Level pot
  • a resistor placed between the Attack pot and ground
  • resistor values
  • OC76 for Q2

From the MK1.5:  

  • 10n output cap (although some Vox carried this)
  • and of course, the OC75 for Q1 is pretty important

SOLA SOUND MK1.75 ‘EL DIABLO’ TONE BENDER  –  0.15″ VERO LAYOUT

So to get something sounding like the video below from pinstripedclips, I needed to use a relatively low gain transistor ~50hfe for Q1 and in some cases the D*A*M dirty hippie mod, often employed to help bias an OC75. 

I added the video below, as this is much closer to what I was getting on the breadboard with most of my transistors.  Also worth noting as mentioned by Phil in the comments, pinstripedclips has a fairly specific set-up, and who knows how that contributes.   



OC84 VERSION


OC76 VERSION


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