Thursday, 3 January 2013

Runoffgroove Thor

If i recall correctly, someone requested this a while ago. I think that's enough for today :)

Runoffgroove's current take on emulating the classic Marshall 100W Super Lead. Read the complete description and history of the circuit from ROG.




14 comments:

  1. Cool, was just about to etch a PCB for this, might just give the vero a shot first. Your on a roll so far this year.

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  2. I played on one of these a while back and liked it lot, but I really liked it best with the bright switch and bottom switch both on. If I wanted to remove the switches from the circuit and just have it wired as if both are always on, should I just connect the bottom sw1 and bottom sw2 and do the same for the bright switch?

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  3. Tag this one, Miro. I've spent ages trying to debug this one only to find I might have really dodgy batch of j201s ( this might explain problems I've had with the umble too - I'll look at that again tomorrow evening).

    But anyway,I went with 4 2n5458s tuned the trimmers by ear and it sounds really lovely, thanks again for another ace layout.

    (Azabache soon!?)

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    1. Thanks for verifying! Weird thing.. I could understand a few bad ones, but whole batch... Good thing you got it working!
      +m

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  4. I am assuming the switches are SPDT on/on Correct?

    Or is it a SPDT On/off/on?

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    1. Only 2 wires are used for each switch so it has to be a SPST simple make or break contact and so 2 position. You could use a SPDT if you want (they seem easier to source than SPST) but you'd just use the centre lug and one of the outer lugs.

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  5. Anyone had any experience with this one? Getting some gating issues with the gain pot. Distortion works when the gain pot is all the way up. Hmmm...

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  6. i built this with a tl061 and i just get a high pitched oscillation noise and no signal. Anybody know how to fix it.

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    1. We can try to help but not with that description, it could quite literally be anything. Have a look at some of the fault finding suggestions here:

      http://tagboardeffects.blogspot.com/2012/05/fault-finding-build.html

      If none of those help post the voltages between all IC and transistor pins and ground to see if those help narrow it down.

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  7. Hey Guys,
    I have built this great circuit and it is just awesome sounding. Much better than most Marshall-in-a-box I tried and a bit fuller than the almighty Wampler Plexi-Drive.
    But, there is one thing that is driving me insane. There is a great deal of hiss on this pedal. Whenever I stack it with a fuzz, a booster or just with another overdrive it stands out as the cause for major hiss.
    Anyone has any idea how to solve this thing? it doesn't matter if the BRIGHT switch is engaged or not, As soon as the VOLUME goes up, the noise becomes audible.

    Thanks,

    http://fuzzquest.blogspot.com/2012/04/rocking-marshall-world.html

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    Replies
    1. Is everything that should be grounded grounded ? Input jack ?

      Try a buffer before and after the circuit, maybe that might help.

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  8. I got this one technically working last finally (I had a few "tracing" errors) but it is finally audible. BUt it is VERY treble and hissing noise. The J201 seems to be the mot prone, any slight modification to its trim pot changes it from dentist drill to pneumatic hammer.

    Not sure what to do - this circuit is very sensitive to it components - Qs and ICs.

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