Wednesday, 27 August 2014

CBS Arbiter Doubler

Thanks to Pawel for his schematic posted on FSB.  I can't find much info on this one or clips, but it is very close to being a Foxx Tone Machine so that should give you a good idea what to expect.

Pawel traced two units with the second being slightly different, using BC109 transistors, the 100K Q3 base resistor is 150K, the 5n cap is 3n3, and all pots are 100K log, so build whichever one takes your fancy, or socket the positions to try both.

Demo of the British Pedal Company Doubler which is a copy









Working voltages as posted by ξεναγός νεκρόπολης:

q1
e 1,11
b 1,65
c 3,95
q2
e 3,49
b 4,02
c 9,08
q3
e 0,56
b 1,16
c 3,55
q4
e 0,21
b 0,78
c 7,82

12 comments:

  1. I can't find any video demos or manufacturers info so unless anyone can point me in the direction of where I can find any, we're stuck with a Foxx Tone Machine comparison

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  2. I'm sure it's slightly different, but British Pedal Company compares their 'Doubler' to the CBS Arbiter version. There's a bitchin' video on their site. Sounds great.

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    Replies
    1. https://www.youtube.com/watch?v=Mvzo09CYskE#t=284

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  3. Wow! Thanks for this one, I just wish the dude in the demo would have used the neck pickup with the tone rolled down for some of the demo LOL
    I like the fuzz tones of this pedal and the upper octave is there for sure... very nice!

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  4. Amazing how this pedal is almost spot on to the foxx tone machine pedal. I have always wanted to make one of those pedals so I may have to make both and toss the one Ilike least in the sale bin :)

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  5. Verified!
    just build it and it worked perfectly from the first moment! ok...the first attempt was with no transistors...it happens to everyone!
    anyway. it's working great, all pots have a good use range.
    i didn't use a stomp for the octave switch. i've used a toggle one..
    i don't have any bc549 and i have only 3 bc109.
    so i've put the bc550 's , witch work really good with this.
    thanks mark
    you are the man!

    ReplyDelete
    Replies
    1. Awesome matey, thanks for verifying :o)

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  6. working voltages
    q1
    e 1,11
    b 1,65
    c 3,95
    q2
    e 3,49
    b 4,02
    c 9,08
    q3
    e 0,56
    b 1,16
    c 3,55
    q4
    e 0,21
    b 0,78
    c 7,82

    ReplyDelete
  7. How to wire up dpdt for octive

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  8. In case anyone cares, I have an original Doubler circuit board that I built a new enclosure for.
    The transistors used are BC173, which are pretty hard to find, but it is a high gain, low noise Silicon NPN transistor. So the BC549 should be a great replacement, unless you care to spend $5 for each transistor.
    My original Doubler has all A50K pots in it, even the Sustain pot, and the 5n cap should be a 3n3 cap.
    If I get a chance, I will try to trace it.

    ReplyDelete