Sunday 22 January 2012

Keeler Pull

I posted this a while ago but someone said they had a problem with the build and so I pulled it and then promptly forgot!  I've just noticed that since then the same guy confirmed the layout is good so I may as well post it up again.

14 comments:

  1. Hmm I've already built one before and that one worked. I just made another one and it doesn't. When engaged, the tone remains completely clean with everything turned up. The volume works (turned all the way is at the same level as bypassed signal) and the tone is working. The texture does work but it's reversed (I guess) because turning it back seems fuller (no clipping though).

    Do you have any idea? There are a lot of 1N34As and I'm wondering if it could be a faulty one? I didn't have a 47u for the power filtering and the closest above 47u I had was 220u. I'm guessing that doesn't affect the pedal in this way.

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  2. i just built this one today. everything does work but has very little gain (distortion), but i assume this is a light (or very light) overdrive. mine has way more output with the volume turned up compared to bypassed with the texture at the minimum. and my texture worked backwards too until i swapped leads 1 and 3 on the texture pot. if you want a little more overdrive using the texture control, try 2N5089's. MPSA18's will give you even more and i'm actually running MPSA13's (super high 3100+ hfe!) darlingtons in mine right now, and it can still get clean with the texture fully CCW, but has way more grit when it's dimed.

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    1. after playing thru it for a while now, IMO, this pedal is just plain boring sounding. while it does offer a fair amount of gain and a little bit of drive, it muffles the top and low end and kinda throws a blanket over your tone (i.e. it loses alot of detail and veils your instrument). it's not my cup of tea in a pedal at all. if you want an awesome low to mid overdrive, i'd recommend building the Fairfield Circuitry "Barbershop" instead. it's an awesome pedal and much more versatile.

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  3. i went back to this one to see if i could get it to sound a bit better. i'm now running MPSA18's in it and changed the second tranny's emotter resistor toa 150R to get more gain (overdrive) out of it. it's still rolling off the highs a bit too much for my taste. does anyone know which cap(s) that i could change to open up the high end or at least scoop the mids a little? if i had the schematic i probably could figure it out.

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  5. okay, i dialed this pedal in where i love it on my bass now. i first tried changing the 68n input cap to a lager value but it didn't make much difference (either to my ear or my RTA tests), so i just went with the 100n there instead of the 68n. then i changed the output cap from a 100n to a 1u and it added a little more extended low end. i replaced the 470r emitter reisistor with a 150R for more gain when running the texture control CCW, and replaced the 18n (the one with the super long leads) with a 27n to remove the 200hz bump and give it a flat response. now with the tone control centered (at noon) and the texture fully CW and A/B'ing the pedal on & off, it is pretty darn transparent. when swapping the 18n tone cap, i tried a 39n, and it sounded good, but it scooped it a little more than i wanted at 200Hz. trying a 33n there scooped it less, and finally settled on the 27n which i think is perfect. this baby is flat all the way down to 30Hz now and i love it. it no longer sounds muffled and veiled and i think that it will work great with a guitar too.
    since i socketed the components that i was experimenting with, i went back and tried the original 100n output cap and could hear that it started rolling the low end off, and the RTA tests shows it to be at around 80Hz and it was much more noticeable now that the mids are flat.

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  6. here's a pic of mine as it is now. since it has more drive, i call it the 'yank' ;-)

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/Yank/yank-01.jpg

    and here's the gut shot:

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/Yank/yank-02.jpg

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  7. Hey Mark, just wondering when you're gonna put up some more new ones?

    best,

    john

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    1. Having a bit of a slow down at the moment John because of the pile of real-job work I've got on, but I'm going to sort out my to do list to get them into some reasonable order of priority and still hope to do 10+ a month. It'll all come down to how much spare time I've got, and how much of it I want to spend reading schematics! :o) But don't worry I won't disappear altogether and will add another couple over the next few days.

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    2. i understand. any hints as to which ones you're considering posting in the near future? i'd love to see a vero of an OKKO Basstard but the only OKKO schematics and vero's that i can find are the Diablo (which i might build anyway, but the current vero layout has standup resistors which i don't care for) and the Dominator.

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    3. The Diablo's in the queue but I've never seen a schematic for the Basstard.

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    4. yeah, me niether. i was thinking of building sabro's vero layout of the diablo but if your's is going to be posted soon, i'd rather build your's. in all of the schematics and veros of them posted, no one seems to show the wiring of the '+' pot on the gain+ (not the gain + boost version) but i'm assuming that it runs thru a stomp switch and is either in series or parallel with the the gain control since it's really just another pot to set the level of the gain (i.e it has no extra boost circuit).

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  8. I built this pedal. I love it. Very mild overdrive. But with single coils, it truely sings. Thanks for posting this one.

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