Wednesday, 28 March 2012

Fred Briggs - Unknown Fuzz



A new fuzz design from myself. It's silicon transistor based but with a difference. I've been playing around with the old Vox Tonebender circuit for a while and this is what sprung from those experimentsTaking inspiration from the Fred Briggs Fuzz I made a few years ago that used "piggy-backed" silicon transistors to emulate lower gain germanium devices I used a couple of piggy backed high gain silicon trannys in the first stage with the hfe set to 25. This first stage pushes a NOS BC108 transistor in the second stage - it sounds great, there's no ear shredding like the usual silicon fuzz boxes just a nice fat low end and a warm mid section. The three controls are for 1; a bass cut, 2; a width control (which adjusts how "wide" and gainy the fuzz sounds) and the third is just a volume control. As you can see there is no "usual" gain control, that's because the only gain control you need is your guitar's volume knob, it'll do everything from mild overdrive right through to full on FuZzZzZzZz.

So, here's the schematic for you:


*NOTE* - To further control the high end and upper mids I would recommend you add in a 2n2 cap in parallel with the 22K resistor and 100kB "Width" pot. It really calms down the harsh frequencies. I included the 2n2 cap on my final build!

*NOTE 2* - Piggy backed transistors are a little picky, you may have to pair up a few 2N5088 transistors before you find a couple that are happy together :-)

I'll be updating this with a sound sample as soon as possible!




2 comments:

  1. I am interested in the piggyback silicon tranny feature you use here. It looks like the bases are directly connected, emitters through the 100k VR but 1 collector is not connected to anything. Am I reading the diagram correctly? Would a diode work instead if this is the case?
    Thanks!

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  2. How nice and excellent post you have shared . Thank you for this well shared . Image Masking | Remove White Background | Product Photo Editing

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