It's a Myrtle Effects "Die Mutant"
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Website blurb...
Myrtle Pedals:
Die Mutant is the culmination of much fiddling with opamps, transistors and diodes to get a distortion which could sizzle and crunch like butter fried bacon.
At it's core is a classic Japanese distortion design based around a Burr Brown opamp using Vishay, WIMA and Panasonic caps as well as carbon film resistors. Foot stomp is high quality, from Small Bear electronics.
Knobs control Volume, Tone, Gain going left to right. There is a switch for changing diode clipping between open, crunchy LED's and "Marshall sounding" NOS silicon diodes. You can push the Mutie a shade harder than your average distortion pedal and the silicon diodes allow for more fuzz pedal style clipping options, coupled with a flexible tone stack you can achieve Tubescreamer boost and grit, MXR Distortion+ sizzle or Muff style mid-scooped savagery.
I can tell you now, this bugger is loud as fook! I Like the diode clipping especially...going from hazy muffy fuzzz, to "You Nasty Bastard" crunchy distortion....I can see us getting along nicely
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Anyone else got any other Myrtle pedals? Handmade in Liverpool UK...