Skreddy - Screwdriver  [traced]

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super velcroboy
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Post by super velcroboy »

guts --
http://i10.tinypic.com/7yque1k.jpg
http://i19.tinypic.com/8dxckth.jpg
http://i2.tinypic.com/8fxk7tj.jpg

this should be enough to get a preliminary schematic going. With my vintage fender, this pedal did not sing as i had hoped. Overall, i thought it was a solid versatile pedal, but not superb everywhere.
from hc forum
skreddy --the Screw Driver and Lunar Module are derivations/enhancements of the FuzzFace circuit. That's how they're the same. From there, they go in two different directions. The Screw Driver has a mosfet input stage, which emphasizes the cleaner side of things and makes it get along with whatever you put in front of it. The Lunar Module is made from all 3 of the same type of oldschool silicon transistors (BC109C), and it's gritty even at its cleanest setting. But at its fuzziest, it does resemble a "muffy" old FuzzFace. Only it's a lot beefier sounding, IMO. Silicon fuzzfaces tend to be a bit on the thin and raspy side, so I made the Lunar Module really fat and smooth sounding (but still with a cutting midrange).
Last edited by super velcroboy on 07 Jan 2008, 20:53, edited 2 times in total.

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Post by Skreddy »

super velcroboy wrote:guts --
http://farm3.static.flickr.com/2416/216 ... 7eac88.jpg
http://farm3.static.flickr.com/2265/216 ... 71a1ee.jpg
http://farm3.static.flickr.com/2170/216 ... 1ac3c2.jpg

this should be enough to get a preliminary schematic going. With my vintage fender, this pedal did not sing as i had hoped. Overall, i thought it was a solid versatile pedal, but not superb everywhere.
from hc forum
dreddy --the Screw Driver and Lunar Module are derivations/enhancements of the FuzzFace circuit. That's how they're the same. From there, they go in two different directions. The Screw Driver has a mosfet input stage, which emphasizes the cleaner side of things and makes it get along with whatever you put in front of it. The Lunar Module is made from all 3 of the same type of oldschool silicon transistors (BC109C), and it's gritty even at its cleanest setting. But at its fuzziest, it does resemble a "muffy" old FuzzFace. Only it's a lot beefier sounding, IMO. Silicon fuzzfaces tend to be a bit on the thin and raspy side, so I made the Lunar Module really fat and smooth sounding (but still with a cutting midrange).
Vintage Fender what, exactly? Also, the Screw Driver's forte isn't so much singing as biting and being responsive to your pick attack.

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soulsonic
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Post by soulsonic »

I don't mean to be nit-picky Velcro, but could you please spell Skreddy's name correctly. You'll screw up the search engines. This isn't HC.

Edit:
Thanks for changing it! :D

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Post by germade »

A friend of mine brought one of these over and gave me major gas for a week. I thought of tracing it but honestly it wouldn't be worth building as to me the price seems reasonable for the amount of work that went into it. I'll probably buy one the next time I've got some scratch saved up.

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Post by Skreddy »

germade wrote:A friend of mine brought one of these over and gave me major gas for a week. I thought of tracing it but honestly it wouldn't be worth building as to me the price seems reasonable for the amount of work that went into it. I'll probably buy one the next time I've got some scratch saved up.
Yeah; it's the kind of thing that may or may not work the same unless you get the same type of germanium transistors and test them for gain and/or adjust the circuit accordingly if yours are different from mine. Though it is fairly stable in most other respects.

It started out as a project to combine a RangeMaster and a FuzzFace into the same box. Then it evolved and morphed over a period of maybe 6 months of near-constant playing and experimentation and tweaking.

So it ended up a mosfet boost into a modified, hybrid fuzz circuit. There's a variable bass control between the mosfet and the fuzz section (which is a cross between a Big Muff tone control and a Joe Gagan variable input cap) I used some other ideas from the Big Muff, like negative feedback and filtering in the fuzz section, and followed it up with a Rat-style tone control.

So there it is. I didn't make up all the ideas that went into making it, but the combination of all these components is fairly unique. The only circuit I know of that is close is the old Colorsound Powerboost/Overdriver (though theirs obviously has the 2-band eq rather than the pre-gain bass and post-gain treble like mine, etc...)

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Post by soulsonic »

Skreddy, have you seen this one of mine? It's my take on the Rangemaster + Fuzz Face idea.

Image

Full size here:
https://www.aronnelson.com/gallery/d/138 ... zleNew.gif

It's adjustable from a light crunch to a heavy square wave fuzz.
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Post by germade »

Nice work Skreddy! I'm rockin a mayo which ate the ramshead I use to have.

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Post by Skreddy »

soulsonic wrote:Skreddy, have you seen this one of mine? It's my take on the Rangemaster + Fuzz Face idea.

Image

Full size here:
https://www.aronnelson.com/gallery/d/138 ... zleNew.gif

It's adjustable from a light crunch to a heavy square wave fuzz.
Looks like that thing rocks! Serious vintage mojo, with the whole roll-the-guitar-volume-knob for variable gain, etc. Kudos.

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Post by prehistoric »

shizzle. nice circuit.

when i looked at it the otherday , i thought it was tonebender derived, but rm>FF is almost the same thing innit?

do you have soundclips of the shizzle?
joe g

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Post by Skreddy »

prehistoric wrote:shizzle.
when i looked at it the otherday , i thought it was tonebender derived, but rm>FF is almost the same thing innit?
That was the whole beauty of the same concept for me. My original idea for the Screw Driver was to make the two separate and have the RM part stompable as in it would turn your FF into a Tone Bender. But my muse led me to the overdrive tones instead of that original plan of fuzz with stompable extra mode. I think that once you start playing with a 3-transistor circuit, it becomes hard to justify going back to just 2.

Oh, and you noticed I dropped your name earlier. :D

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Post by prehistoric »

ps- have you ever tried it with a 2n3906 as Q2?
might be cool, probably more gain and slightly tighter bass

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Post by soulsonic »

prehistoric wrote:shizzle. nice circuit.

when i looked at it the otherday , i thought it was tonebender derived, but rm>FF is almost the same thing innit?

do you have soundclips of the shizzle?
joe g
I have one recorded, but I have to edit it down cuz it's long and boring.
I got the idea for it when I was playing with my Dunlop germanium Fuzz Face one day and I was wanting a cooler sound from it, so I tried boosting it with this Rangemaster style booster I had built. It sounded way cool, so I played around with giving it more controls and that was it. I'll try to get the clip posted a little later.

I'm totally going to use your input cap blend pot idea in a future version of this circuit. That rotary switch is a real bear to wire up.

Not tried any silicon in it yet, but I plan on trying an all-silicon version that's less finnicky to build - that's the one I want to have the cap blender in.
"Analog electronics in music is dead. Analog effects pedal design is a dead art." - Fran

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Post by prehistoric »

hi skreddy, note noted, thanks as always!

in my opinion, you did good when you eliminated the 2nd footswitch for the RM. there are 2 major reasons why i oppose the two stomp concept, besides the obvious extra space/ time and work of a second switch

1. in real life stage situations, a second switch for a second function rarely ever works for on- the- fly switching.

it is usually unlkely your gain setting for the RM will also be the EXACT same setting you like to drive the fuzz section into its best tone. most of the time there will be a level or gain (or both!) mismatch betweeen modes - requiring a bunch of extra parts or engineering to try and get it to match, or you have to give the user another knob to have control over 'function A '(RM in this case).
now, even if you give the customer a 'level' control for the RM, it will need a second signal path(+switch) to bypass this control or you are locked into sharing the level setting for the fuzz. these comments are based on personal stage experience trying to use all the functions the skyripper had to offer before giving up and building a stand alone RM to let the skyripper have its own settings.


2. seems like good marketing to give the customer a 2 for 1,but my experience is that most customers are getting set up for unmet expectations with these dual peds. might be good for bedroom tweakers, but to me a pedal should be designed to work well on stage as primary consideration. a good stage pedal can usually make the transition to bedroom queen, but the other way around is rare.

anyway, not sure how you reached your conclusion, just letting you know i think you did the right thing.

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Post by prehistoric »


I have one recorded, but I have to edit it down cuz it's long and boring.
DUDE!
you obviously missed my 16 minutes of nonsense over at the old ampage clips site.
can never be too long IMO ha ha
i have a bunch of 2 and 3 minutes doodles on youtube now

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Post by soulsonic »

Okay, ask and ye shall receive.

It gets really cool about 3 minutes in.

https://www.aronnelson.com/gallery/v/sou ... o.mp3.html
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Post by prehistoric »

i like it, very gnarly. i like the way the notes almost flub out when the bassier settings are in play. that is a good bloom factor.

the treblier settings are nice and tight, like a fuzzy dist pedal.good pick attack on all settings.

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Post by soulsonic »

Thanks! I'm all about pick attack, that's a "signature" I try to have in everything I build, mostly because I don't care for soft attack sounds. It sounds really wicked on the neck pickup with the guitar's tone knob rolled all the way down - that takes out alot of the sharp attack that makes the bassier settings flub and it starts sounding really synth-y.
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Post by seniorLoco »

i got a broken one coming in tonight ...hope not a dead germ :?

Hey Skreddzer .... might need your help on this as i was told the owner fell asleep leaving his pedals on :?
"Curiosity may have killed the cat, but it saved the mice, who ate the cheese."

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Post by Skreddy »

seniorLoco wrote:i got a broken one coming in tonight ...hope not a dead germ :?

Hey Skreddzer .... might need your help on this as i was told the owner fell asleep leaving his pedals on :?
Okay. I guess the cost to ship was the main factor in this decision--no biggie; glad to help. You know what? The first thing I'd look at is the mosfet. Like Zvex, I put a whole bunch of units out there without protection zeners. So I can send you a BS170. The symptom would (obviously) be that all you get is a tiny bit of hiss out of it. If that's not it, then tell me what it's (not) doing?...

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Post by seniorLoco »

Oh that was quick ...thanks ...i got heaps of BS170 :D

So ...i should mod with protection zeners ?
"Curiosity may have killed the cat, but it saved the mice, who ate the cheese."

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