Monday, 3 December 2012

Marshall Drive Master

From an 80s Marshall ad: Fire your cartage company. You don't need a rack full of gear to get distortion that goes from subtle to stun gun.  If you want all the range of a top studio pro, the Drive Master is for you.






14 comments:

  1. O YEAH! Me likey a LOT! This WILL get built during Xmas. Only way to achieve https://www.youtube.com/watch?v=VQhuoY5h2kE short of cranking a wall of Marshall amps.
    The neighbors will be very grateful for this stocking stuffer!

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  2. Built this Pedal. With "Marshall" expected something special and it did not disappoint. Great saturation and sustain. Thanks.

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    1. Excellent, thanks for verifying Jon

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  3. Hi!

    I built this recently (thank you so much for the layout and all the AMAZING work you guys do), and I am thinking of modifying this build for bass. i tune pretty low, so i would need plenty of lows going through. Which caps would i have to change? Any info would be really appreciated! THANKS!

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    1. There's a high pass filter at the first opamp stage which consists of the 2K2 resistor and 100n cap to ground. That gives you a cut off frequency of about 720hz which means a lot of the low frequencies are going to be attenuated. To lower the point where attenuation starts you need to increase the value or the resistor, or cap, or both. I'd experiment there to fine tune it to your own taste.

      Increasing the resistor value will also increase input impedance so there may be audible differences if you swap the resistor or the cap, even if the cut off frequency remained the same by the changes.

      Check out this calculator to help decide what values to use in there:

      http://sim.okawa-denshi.jp/en/CRhikeisan.htm

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    2. Thank you so much. Do you think that lowering the cut off frequency to say 40 or 60hz would be excessive for a bass tuned down to B? Would it cause problems to other pedals later in the chain? Many thanx

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    3. Wrote a lot of nonesense about this one... Forgive me, I am still on the learning curve! ^^
      Anyway... I found a schematic that was sending a number of components to VRef instead of ground, and that was including different values for a few components.
      I tried the VRef/ground thing, and it was a complete fail. Restored the connections to ground, and it now works like a charm. :)
      Here's a pic of my build, the blue channel being a Guv'nor and the red one the Drive Master:
      http://imageshack.us/photo/my-images/832/3ush.jpg/

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  5. I just built this one today and I like it a lot. for use with a bass I modded the HP filter stage 2K2 resistor and 220n cap with a 3K9 and a 1u. there's no loss of low end now.

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  6. pics:

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/DriveMaster/drmaster-01.jpg

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/DriveMaster/drmaster-02.jpg

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  7. Built this today and must say this has a great range of distortion. Third successful bid of the weekend so time to make some sounds.

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  8. If the pedal is on ,and the red led is on or off ,sorry my English is no good

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