Sunday, 14 February 2010

Soulsonic JFET Boost

4 comments:

  1. This one here. Tag it.

    I took the source to breadboarded trimmer lug 3 and ground to lug 2. Measured the drain with that trimmer and matched it to 4,98V. Then measured the trimmer, and it was 1,067K. Then i just wen't through a few 1K resistors (by the way, i used 1W resistors to get some more mojo look:)) and found one that measured 1,05K and went with that. Sadly that gave me just 4,81V for SK117 drain, but i think that is close enough.

    It was pretty loud and just got louder with the gain pot - plus there was some static from the circuit. So i solved those by adding a A100K "master volume" (out to lug 3, new output to lug 2 and lug 1 to ground) and placing a 100µF power filter cap over the input lug of the board.

    Anyway. I wouldn't exactly call it clean boost, but more like a jfet overdriving boost with touch of tube feel to it. You'll know what i mean.. This is as much of a "boost" as OD250 is a "preamp". Still nice. Really nice.
    +m

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    Replies
    1. Top man! You're certainly working your way through these oldies! :o)

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    2. Got day off tomorrow, so i might do one newer then... :)
      +m

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    3. Today, #2:
      http://mirosol.kapsi.fi/varasto/boxes/SoulBoost.jpg
      +m

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