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Thread: Jazz Chorus - mod to crunch circuit

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    Senior Member Guitarist's Avatar
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    Jazz Chorus - mod to crunch circuit

    Should I bother? A friend just scored an olde Roland in trade and it works great. Perhaps a minor tweet to this discrete circuit is advisable or leave it stock and use a pedal.
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    Old Timer J M Fahey's Avatar
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    Just use an external pedal, any one you like.

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    Juan Manuel Fahey

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    Bent Member Chuck H's Avatar
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    The older JC was never loved for it's distortion circuit. But Roland has some newer distortion circuits that I thought were very good. I don't know how similar the topology might be between the old and newer circuits, but if they're similar enough you might be able to change circuit values to be more like their newer, better sounding circuit rather than tweaking into unknown territory. Otherwise, if topology is too dissimilar I would probably just use a pedal.

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    "In fact when I run into problems working on electronic circuirts, there are so many times that when I finally track it down, the source of the problem is located between my soldering iron and my seat." SoulFetish

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    OK, just put it back together. The dirty channel is just rather bassy due to the 1uF cap there and the circuit kinda in parallel with itself anyways, Centaur like?!
    All the amp really needed was contact cleaner for the pots. It was rather impressive to look at, well built.

    Thank you and good day...!

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