Pages

▼

Sunday, 28 September 2014

Blade VSC Preamp, modified

Ran into a schematic of a preamp on-board circuit found in Blade brand guitars. The original called for LM4580 dual opamp, other channel unused. So i drew this layout for a single channel chip and added volume control, power filtering etc. You could try on a number of single opamps to see which sounds best to you. I'd also suggest trying linear taper for volume control. Should make a nice mids booster or a simple box that'll fatten your tone.


at

11 comments:

  1. Unknown30 September 2014 at 09:04

    gotta try this!
    Thanks miro!

    ReplyDelete
  2. Unknown30 September 2014 at 20:01

    Verified. Used a LM741.

    ReplyDelete
    Replies
    1. mirosol30 September 2014 at 20:54

      Cheers! I'll tag it.

      How does it sound?
      +m

      Delete
    2. Unknown1 October 2014 at 17:04

      It sounds like a mid boost, which becomes more of an overdrive when the Mids are turned up. This can be compensated by turning down the Volume. I am going to use this one as a pre-gain stage for a sixties type of fuzz.

      Delete
    3. Meek2 October 2014 at 00:31

      i like the time vero got posted :P

      Delete
    4. Bohemian H3 October 2014 at 14:17

      2nd that, Egon.

      Delete
    5. mirosol3 October 2014 at 14:48

      Heehee :) I recently noticed that the time i've created my FSB account was 18:15. And one guy i sent a parcel to today had his phone number ending in ..2907. 21:12 looks cool, but once you start seeing semiconductor type numbers everywhere... :)
      +m

      Delete
  3. Mr.Baiser2 June 2016 at 23:21

    I'm planning to build this as onboard preamp, without that extra volume pot and with a trim pot for mids. But how should I connect it to the guitar (stratocaster) circuit? Before or after the stock volume pot? Best would be a three position switch: "up" position - bosst actice; "middle position" - true bypass for midboost; "down" position - true bypass and battery switched off

    ReplyDelete
  4. Mr.Baiser7 June 2016 at 20:23

    Why did you increase the input resistor? It's a much smaller value in a Blade Guitar, as the VSC input resistance is in parallel with the volume pot.

    ReplyDelete
    Replies
    1. mirosol7 June 2016 at 21:01

      You should ask user Induction at FSB:
      http://www.freestompboxes.org/viewtopic.php?f=7&t=18827&p=201441#p220902
      The layout is per the available schematic. Granted, it should be called "Zorro mid boost by Induction".
      +m

      Delete
  5. Norjen18 December 2021 at 17:54

    Does this work as an on-board version if I solder the Volume 2 output lug straight into guitar output jack? Basically just replacing the standard guitar volume pot with the 100K described here.

    ReplyDelete