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Evil Harmonic Overdriver Fuzz (18JUL2016 Schem added)

Started by Lubdar, July 16, 2016, 07:40:45 PM

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Lubdar

It will, i did a youtube video comparing different types of 2n5089s for the fuzz stage. Apparently the beta parameter is a part/(result?) of the manufacturing process, which may be why national semiconductor 2n5089s worked better in reverse active mode than TI, or ON.

The 7 transistor fuzzwar wasn't designed that well. The whole reason I got into this hobby was because of the DBA Armageddon Pedals. Over the next couple months I'll be posting my progress thus far.

Using the 910k, 180k, 390 ohm bias setup works for the MPSA05s. It should work in the 7 transistor fuzzwar that exists on your layout. It will be darker than when 2n5089s are used, but that could be taken care of with the tone stack. If biased properly, in reverse active mode, 2n5089s have higher gain and more treble content than MPSA05.  If you socketed your transistors, you should be able to put in MSPA05s (i got a roll from mouser) and they should work.

Also, test it out, but the diode configuration after the tonestack in the fuzz war doesn't do what people think its doing based off of the schems i have seen.  Early DBA stuff was largely just cascaded boosts. That's why in some pedals I've seen the diodes not actually functioning in the post tonestack.  Either someone traced it wrong, or DBA implemented the idea incorrectly....

Hope this helps.
  Lubdar
(--c^.^)--c

storyboardist

Thanks man. Cody, you payin' attention?  ;D Cody and I have been talking about the 7-tranny Fuzz War for the better part of a week. It seems a lot of the 680n caps are actually 100n from gut shots. Might help with the dark tone with MPSA05s. In those same gut shots, those diodes after the tone stack are populated but with the 27k resistor connecting them to the base of Q6 removed, or just completely removed from the circuit board in later pcbs.
Guy behind Effects Layouts

selfdestroyer

HAHA I am all over it. Still have the layout populated and ready to try the suggestions. I will report back!

Cody

Lubdar

100nf gives it more crunch, i used a mix of 100nf and 470nf for coupling caps. 680 is just way to much mud for the sound I was looking for.
Heh, I have pages and pages of my attempts at schems and my documentation of sounds and the components going into it....
But yes, at the end it was 7 boosts in a circuit.

As i mentioned before the gain pot from the collector of q1 is an idea not implemented correctly You're going ! you'd be better suiting using a 1M pot as a signal limiter at the beginning of the circuit, and setting that pot as a 390 ohm resistor instead.

Fyi the 410k/100k resistors to V+ in the first couple of stages can be set so all are 910k/180k if things don't work out right. The 410K/100K is just an off biased value, which may or may not sound good to your ears...
(--c^.^)--c

raulduke

This looks great, and kudos on such a neat design and layout (love the 3PDT PCB).

flanagan0718

I just finished a build for some one that was a
DBA Sound Saw -> DBA Harmonic Transformer -> order switcher -> Moodring -> FX loop / Blend
Long story short, the HT sounds AWESOME! I'm very interested in hearing this too.

storyboardist

I made a perf/single sided pcb layout for this if anyone's interested. I think Cody's already etched it, but not sure if he's populated/tested it yet.

Guy behind Effects Layouts