Sonic Tone Effects Tone Bender MkI


Sonic Tone Effects

The Sonic Tone Effects Tone Bender MkI is a reproduction of the British Made MKI Tone Bender the one that started it all. Used by many famous players such as Jeff Beck, Mick Ronson and Pete Townshend just to name a few.

The original circuit used an OC75 Mullard and two Texas Instruments 2G381's. In this reproduction an OC75 Mullard/Phillips and two Phillips AC125's were used. As you may know the 2G381's are super scarce. There isn't really anything special about the 2G381's likely the reason for using them was because they were cheap and easy to obtain back in the day.

The MKI is known as the most notoriously difficult circuit to bias correctly. This is probably why they only made a short run of the MKI's and switched to the more stable MKII circuit.

This pedal was built in a 76 degree controlled environment to ensure a quality build and tuned to give it the fantastic harmonics and long thick sustain with a bit of sizzle and spit this circuit is known for. When testing this pedal in different temperatures I found that under 70 degrees you will get a bit more sizzle and spit and at 76-86 is when you get the best killer tones from this circuit.


  • Black and lime green swirl painted enclosure.
  • Daka-ware vintage style chicken head knobs
  • Neutrik 1/4" audio jacks
  • Alpha 16mm potentiometers
  • True Bypass DPDT foot switch
  • Vishay/Roederstein film caps
  • BC blue electrolytic caps
  • Xicon carbon film resistors
  • Shielded cable

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