Friday 20 November 2020

Boss SP-1 Spectrum

 A fairly rare old Boss eq pedal which is rarely cloned due to the dual 10kA/10kC Balance control. However, it is quite easy to make your own if you have a dual 10kA pot and a single 10kA pot on hand. Custom pot tuturial and schematic is avaiable HERE

 

 




8 comments:

  1. Amazing. thanks! Going to have to try this out

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  2. Verified. Cool effect, although not worth the price these are selling for. It's very useful after fuzz for tone shaping.
    I'm counting 24 cuts.

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  3. Also I made my own 10ka/10kc dual pot using the link above. I only had the parts for linear taper, and the sweep works great

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    1. Excellent! Thank a lot! Tagged.
      The the prices online are bonkers...but luckily we can build our own now...

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  4. Just wondering but as C is a reverse log taper pot and A is log taper could we even just wire the 2nd part of the dual gang in reverse? So instead of 456 solder 654. Im happy to try and make the A/C pot but just thought it may be easier to do thile reverse wiring

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  5. What does the trimpot control/change?

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    1. It controls how much the specific frequency (dialed in by the "spectrum" control ) is boosted.

      By the way, to answer your previous question about wiring the second gang of a dual-gang A-taper pot in reverse... in this case, it wouldn't work. That pot controls the blend between the direct signal and the boosted EQ signal; each gang performs the same function at different points in the circuit. If you wire half the pot in reverse, then the second gang will nullify the first and it won't work at all.

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    2. Awesome thanks on both fronts. I ended up making the 10kA/10kC anyway from the linked description. Was easier than i expected. Look forward to having a play of it tomorrow

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