Pages

▼

Saturday, 5 April 2014

Barber Gain Changer

Another versatile overdrive here from Dave Barber, and as usual at a very fair price.  If you want to fine tune the mids and bass content to suit your own style or gear, consider socketing the 7K5 resistor on the right for mids, and the 22K resistor at the top for bass.

Info about the original:

Measuring only 2.3” wide, the NEW Barber Gain-Changer harnesses a vast spectrum of EQ and gain. Flick the toggle one way and you have sweet very low-gain overdrive, flick it the other way and you get wildly charged harmonic content of our much praised unLimiTeD distortion. Pop over to the other toggle-switch and you can volley between the flat sweet-EQ of the LTD SR , the vintage snarling-fat-EQ of our classic LTD v2 or a new voice that combines flat EQ with a little added fatness. Combine all these different options together and you have a super-versatile harmonic beast. Our goal was to shrink the size of our pedals and retain all the ultra-high quality electronics and build quality that we are world famous for. In the end, it’s almost impossible to miss the target if you are shopping for a new overdrive for your rig, “it’s like shooting fish in a barrel Jethro.”

 The Gain-Changer has real honest solder lugs for jacks, True-bypass footswitch, toggles and pots. There are no worries about PCB mounted thru-panel parts that can’t be serviced on the road, or that lead to high cost repairs. Nothing but the best tried and true hand-built methods adorn the interior of the Barber Electronics Gain-Changer. The Gain-Changer has a generous 2 1/2” of clearance between the front edge of the footswitch and the back edge of the knobs, no more worries about changing your settings with each click of your footswitch. Buy a hand-built Barber Gain-Changer, and enter a world of immense overdrive possibilities.







at

30 comments:

  1. Unknown5 April 2014 at 20:55

    Built this one this afternoon, it´s working great but reverse gain 1 and gain 3. Everything Barber does sounds great and so does this one. Thanks a lot for the layout

    ReplyDelete
    Replies
    1. IvIark5 April 2014 at 21:11

      Can't believe I got the gain lug numbering wrong!! I thought I knew what I was talking about with pots now! :o) Anyway that's excellent, thanks for verifying Bastian

      Delete
    2. Unknown13 April 2014 at 15:08

      Hi Ivlark. This is the second layout I did (noisy cricket mk II was my first) built, and it is working great, Thank you very much for your great work, it's fantastic ! (even if i did swap gain lug 1 and 3 after testing ;) ). Good job !

      Delete
    3. Unknown15 September 2014 at 13:51

      Reboxed it last month, really love Barber effects look and feel. Take this as a tribute : https://www.facebook.com/photo.php?fbid=538729569592587&l=c541d12d07
      I managed to put a battery in the box, really great layout and great sounding effect.

      Delete
    4. IvIark15 September 2014 at 14:09

      Nice job, thanks for sharing the pic

      Delete
  2. Unknown5 April 2014 at 21:31

    Haha - you´re the best! I used to wait for verified layouts before building. But with you, i know they always work when posting a new layout! Thanks again!

    ReplyDelete
  3. carvingbone6 April 2014 at 09:48

    Hi there, where would I find schematic for this please? Cheers Steve

    ReplyDelete
  4. Unknown11 April 2014 at 23:40

    I'm learning as I go here.. d1 d2 d3 and d4 would appear to be a diode rectifier with a cap in the center.. whats going on here and is there another term for this layout ?

    ReplyDelete
    Replies
    1. IvIark11 April 2014 at 23:57

      They're two series anti-parallel diodes in the feedback loop of the opamp, so simply for clipping and distorting the signal. You'll see those a lot in these layouts in both opamp and transistor circuits. 4 diodes like this clips less than just having a single pair of anti parallel diodes. Both of the above give you symmetrical clipping and so both halves of the waveform are clipped the same, but sometimes you'll see just one diode in one direction and two in the other which give you asymmetrical clipping where one side of the wave form clips more than the other. All variations with subtle differences.

      Delete
    2. Unknown12 April 2014 at 00:07

      Thanks, making more sense.. I've drawn the circuit out further and compared it to others and realized that it was partially the way i was drawing it that was confusing me.. ;)

      Delete
  5. fixxe12 May 2014 at 20:58

    I get quite the volume jump when I switch the gain switch. Is this normal?

    ReplyDelete
  6. Unknown15 October 2014 at 13:48

    In the original schematic there is a D5. I can't find it in your Layout. Why is that?

    ReplyDelete
    Replies
    1. IvIark15 October 2014 at 16:00

      I haven't got the schematic in front of me but it will almost certainly be a parallel reverse polarity protection diode, which I always omit because I think they're stupid.

      Delete
  7. Rambling Composer3 March 2015 at 23:54

    I'm hoping to build a super tweakable BB version of this circuit and have some questions. First off I'd like to replace the mid & bass resistors with pots. Thinking 10k for the mid and 50k for the bass, any opinions on taper? Also, could the gain switch portion of the circuit have a resistor replaced with a pot that would adjust the crunch level?

    ReplyDelete
  8. Unknown21 April 2016 at 16:12

    In the hopes of a foot switchable lead setting, I've added 2 volume pots, 2 gain pots, and 2 eq switches toggled via 3pdt. The volume/gain work fine but the eq makes a pop, if either the 8k2 or 16k are selected. I own a gain changer and it also pops if you toggle the eq switch. Is there anything I can do to eliminate the pop when those parallel resistors are toggled? Thanks!

    ReplyDelete
  9. Raphiro9 May 2016 at 22:47

    (sorry for my bad english)
    i'm having some trouble with the gain switch. When lugs 1 and 2 are connected, there is no sound at all. When lugs 2 and 3 are connected, the pedal works perfectly. Now i just strip off the switch and the pedal works.

    ReplyDelete
    Replies
    1. Raphiro15 May 2016 at 01:37

      I dont think i've made myself clear: only part of the pedal works perfectly, just in one position of the gain switch. Anyone here had the same problem?

      Delete
  10. lonetone8325 September 2016 at 00:18

    what is the 91R resistor in the top right corner of the layout? is it 9.1k?

    ReplyDelete
    Replies
    1. IvIark26 September 2016 at 00:29

      No it's 91 ohms. It's just a current limiting resistor for the 9V supply, so just use a 100 ohm and it'll be fine. I wouldn't buy that value especially for the job it's doing

      Delete
  11. GaryG4 April 2018 at 14:09

    So is the third EQ option simply the switches off position, neither resistor connected? Cheers.

    ReplyDelete
  12. Unknown10 September 2018 at 13:22

    Hi all, from France . You can find the Barber original schematic on the Barber Web site . Link is here : http://www.barberelectronics.com/Gain_Changer_service_schematic.pdf

    ReplyDelete
  13. Unknown10 September 2018 at 13:33

    Madbean was working on the Gain Changer .... But i d'ont like it ... The PCB need a double tace of copper, and the result is that it's not so good . In first, the trace are very fine ( 0,65 mm, that is very small for DIY ). I use 1 mm for my trace with my CNC router ... Madbean add a mod for the tone, with two trigger for set the Bass and the mid range . It's not nécessary . And for the building with the PCB DIY, it's impossible to put the Vias copper inserts for the SPDT ! Il love this pedal . Bests regards . Pascal Benard Metasound . Here is a link for the Madbean Schematic ::: http://www.madbeanpedals.com/EP/schematics/LabRat.gif

    ReplyDelete
  14. Jcows20 March 2020 at 01:28

    How important are the 56n caps I subbed 47n and also subbed in resistors for the 13.3k and 16k I used like 12k and 15k but the pedal is not working properly, its fuzzy and gated and cuts in and out.

    ReplyDelete
  15. Elijah-Baley20 March 2020 at 09:32

    The 56nF is the input cap, your 47nF cut a bit the low end, but I think there's no a big difference. Instead, 12k and 15k are cloer enough to the stock 13.3k and 16k, so no problem with these resistors.
    Your problem is caused from some mistake, probably. I didn't realized this circuit, but it should be verified.
    Check the position of all the components and wires, the values of the parts... Look well the solder side in case of bridge between the stripes.

    ReplyDelete
    Replies
    1. Elijah-Baley20 March 2020 at 11:19

      For the other 56nF is almost the same thing. Maybe a bit of more bass with the 56nF in the tone section.

      Delete
  16. Jcows21 March 2020 at 01:27

    Built a new one and it's working well. Couldn't get the first one working, I might have burnt something up undoing a solder bridge oh well. I had to swap gain 1 and gain 3 for it to work like a typical gain pot. Thanks for the help, I'm not certain when a substitution is acceptable or detrimental to a circuit. It's a great circuit I highly recommend this, the paisley drive, and the timmy.

    ReplyDelete
  17. Unknown4 August 2020 at 06:45

    I've just finished building this as a "Covid isolation" project. My lead guitarist has a proper one and uses it all the time, it's that good. I'm not at all disappointed with my one and it sounds great. I substituted the gain switch for a DPDT and used a tricolour LED so I get green for low gain and red for hi gain. As always, graphics are the hard part :) Thanks for the great layout!

    ReplyDelete
  18. j-pee30 May 2022 at 18:17

    in this 2020 interview David Barber speaks really in depth and extensively about this pedal... and all its previous versions....

    https://www.youtube.com/watch?v=JVwATOzWvNY

    ReplyDelete