Friday 25 January 2013

DOD FX55 Distortion

This one apparently has the same circuit board as the FX50. Original used TL062, so TL061 is probably the right chip for the job. Like FX50, the other half of the opamp didn't touch the signal path when engaged at all, so i decided to go with a single.



9 comments:

  1. So, since i built the fx50, i just changed three components that differ from the schematics and noticed that the 3n9 should not me a cap, it's actually a 3M9 resistor, after those changes, it works well too.

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    1. True. I have misread it, as it looks like "3.9n in fx55"

      I'll post fixed one once i get back to my desk...
      +m

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  2. Is this layout is tailored to the TL061 chip? I have a TL062cp I'd love to use.

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    1. You can't use a TL062, it's a dual opamp with a different pin layout. You could use an LM741, TL071, LF351 or lots of other single opamps, but a dual opamp would need a new layout completely.

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  3. This comment has been removed by the author.

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  4. Built this one recent rainy Sunday just for something to kill time. Made mine with a TL071 as i had some spare. For a pedal that i built out of spares i'd forgotten about (i'd like to think that's 'free' but we all know better) it's not bad at all. A nice amount of gain, integrated well into a chain with a BB preamp & DOD compressor in front of it, hooked up to a low gain amp. Pedals + amp give me everything from a slightly dirty sound right through to thrash :)

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  5. HEY ROBS WHATCHA RUNNIN FOR YA RIG???

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  6. effectslayouts has a 47uf electrolytic in their version of the circuit in addition to the dual 10uf electrolytic caps. http://effectslayouts.blogspot.com/2014/12/dod-fx55-distortion-2-knob-version.html

    Is it omitted in your stripboard version for a reason? Will the pedal function just fine without it? Same question applies to using a 1N4001 in the D5 position instead of a 1N5817. Does it matter all that much if I octuple-check that I've wired my power plug up correctly?

    Thanks in advance from a pedal noob.

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  7. My build has a high pitched squeal for the last 20% of the gain pot.
    Should I introduce a small cap somewhere? If so, where?

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