Traced by GratefulEight, this overdrive seems like a circuit worth to try out.
From the source: The Earth Drive is the ultimate boost/overdrive pedal, designed to
retain your instrument's natural character while providing an organic,
full-bodied, yet transparent sound.
Use the Earth Drive as a
clean boost to add warmth and smoothing, or turn up the drive knob and
get a wide spectrum of overdrive harmonics and singing sustain. The
Earth Drive has a huge range of boost control with its volume knob,
while the tone knob helps you perfectly dial in the treble response.
Whether
you play bass, pedal-steel, electric piano, electric guitar, organ,
whatever, the Earth Drive is quite possibly the most useful and
versatile drive pedal you've ever heard.
Tone knob value is missing
ReplyDeleteNot anymore. Thx.
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also missing a cut for D5.
DeleteI haven't built it yet but it's interesting me. I will this weekend and report back.
@refused did you already verified this layout?
DeleteI think it should be a 100pf ceramic too.
ReplyDeleteOn GratefulEight trace that is 100p, while it's 10p in Manfred's redrawn schem. 100p seems correct..
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Just had a crack at this one but I'm getting nothing so far. Will have a better look tomorrow, but I can't see anything obvious on first inspection.
DeleteI checked it again and noticed one more flaw. The 4n7 on the recovery input was tied to vref instead of ground. In my understanding that should not prevent the circuit from functioning. But i's fixed now. Try that? And maybe a probe to see where the signal dies?
DeleteOtherwise this *should* be per schematic and since it's pretty basic opamp circuit, it should work..
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ReplyDeleteShould the cut underneath the 22uf cap be there? Looking at the Pedal PCB Tellurian drive schematic, it looks like pin 7 of the op amp should be connected to the 680nf cap to volume? Apologies if I'm missing something. Thanks M
ReplyDeleteNo! That cut should not be there. Thanks for the heads up!
Deletei'll fix the layout today.
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Now fixed. I bet Ben Spinks' build will come to life if the top right cut on the incorrect version gets shorted...
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Yep, very well spotted micadoo. Works fine now, and a cool sounding circuit it is too!
DeleteNice!
DeleteCan't believe i did't catch that one myself when i double checked it..
So! Should i tag it?
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Yup, go ahead and tag it.
DeleteAlso, I used a TL072 as the IC and D9E's for the Ge's. It's a surprising pedal now i've got it boxed. Very big range of sounds. From boost to quite heavy lead tones and seriously loud. It's got a certain character that's for sure. Very lively. The only down side for me is that it's *very* bright. 8 - 9 o clock on the tone knob is where i'd normally expect 12 to be.
DeleteGreat! I finally got on a computer and tagged this.
DeleteThe tone bot is C50K, so changing that to B or even A taper could make the turn act more like standard tone control. My guess would be that B taper would work better.
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The B taper worked perfectly. Much more normal tone control now. Thanks, Ben.
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