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Been curious about this pedal for a while. Someone by my studio was throwing out a load of old electronic bits and I found a few bc107s in there so I thought I better give it a go.
Just breadboarded it. I think it's a keeper.
What I've got seems to work best when biased for gating otherwise it's a bit of a limp silicon fuzz face. Nice spit and sizzle from this fuzz and some very convincing synth tones, especially when double-tracked. Don't know if it's much different from say, a Wolf Computer though as I've never built a silicon fuzz with a bias control before. The schems online call for 25uf electros but I noticed the original used 12uf so I used 10s. I've read 200-300hfe for the trannies but mine was sounding a bit tame so I upped q1 to 400 and that pepped it up. Q1 and 2 were originally BC107 but I've swapped Q1 for a 2sc536. Don't think the trannies make any difference.
It was your site Ian that got me interested in the pedal in the first place. I'd never heard of it before. I used the schematic that comes up first on Google images and just subbed the 25uf caps. Been playing it a lot so it's gonna have to go in an enclosure soon.
ghost_effects wrote:thats because the 'official' wem sharptone pedal is using goodness knows what circuit in there haha! fuzzrite maybe?
If you pause that first video at 1:06 you can see the layout of the circuit. Definitely no 25, 10, or 12.5 uF electros. Can't see the values but the only electro is one that was added across the power rails for stiffening/filtering. Looks like just 4 470K resistors too. There appears to be some connections made underneath the board so can't quite trace it properly, but you can make a good guess.
Ben79 wrote: Strange that Sharptone pedal sounds so different when the original is so easy to build and uses abundant parts.
its just plain weird isn't it? If I was working with WEM the first thing I would ask would be "lets see the schematics" haha, they must have everything recorded somewhere surely!?
the sharptone peps are now less than half price on Ebay, he should just rip the guts out and start again!
Yeah, or copy an original unit. Also strange that given the original was on a PCB, he went for tag board. I like tagboard but surely it makes more sense to use a PCB - quicker, easier and cheaper to build if you're doing batches, and vintage correct if you care about that sort of thing, which he must think his customers do or he wouldn't have hardwired the output cable. In fact the hardwired output cable seems to be the only thing true to the original! But I like the messy silicon fuzz his pedal produces, whatever it is.
Excuse a reply to a year-old thread but, as the official distributor of the official re-issue of the WEM Rush Pep Box, I feel compelled to respond to some of the posts above when this particular pedal's circuit was discussed.
Please be advised that I have it on good authority that the WEM Rush Pep Box official re-issue (pictured below) is based on an early, prototype circuit.
Ro_S wrote:
Please be advised that I have it on good authority that the WEM Rush Pep Box official re-issue (pictured below) is based on an early, prototype circuit.
That's officially weird, Ro_S.
Why wouldn't they base the reissue on the standard production version of the circuit?
psychic vampire. wrote:The important take away from this thread: Taoism and Ring Modulators go together?
…...........................… Sweet dealin's: here "Now, of course, Strega is not a Minimoog… and I am not Sun Ra" - dude from MAKENOISE #GreenRinger
Ro_S wrote:
Please be advised that I have it on good authority that the WEM Rush Pep Box official re-issue (pictured below) is based on an early, prototype circuit.
That's officially weird, Ro_S.
Why wouldn't they base the reissue on the standard production version of the circuit?
Re: the official re-issue of the Wem Rush Pep Box, made by SharptoneFX -
The builder advised me that the original 1966 production version of the 'mark 1' (wedge-shaped) Wem Rush Pep Box sounded muddy and lacked definition. He tweaked and altered the circuit to make it sound better, basing it on a prototype circuit.
The hard-wired output cable on the re-issue was specified by Charlie Watkins/WEM.
