TRBX-505 rewiring question: pot value for volume and blend

Discussion in 'Pickups & Electronics [BG]' started by Aloe, Apr 23, 2017.

  1. Aloe


    Apr 10, 2016

    I'm going to swap out the stock electronics in Yamaha TRBX-505 with an Aguilar preamp.

    Aguilar manual says `use the pots suggested by pickups' manufacturer'. Actually I was going to keep those pots, but it seems like the stock volume and blend pots are wired directly to the stock preamp board (i.e. without cables -- they just sit on the board), so it may be easier to swap it all.

    TRBX-505 electronics have a A250K pot for blending (probably that's not a real blend pot, as pickups seem blended at the preamp, not at this pot) and something marked `3J2' as a volume pot (googled and still have no idea what it is). The pickups are two alnico humbuckers.

    From what I've read it seems like I want a 500k blending pot and a 250/500 one for volume. But I'm really not sure.

    Any suggestions? Thanks.
  2. If you have passive pickups, then use 250k or 500k.

    If you have active pickups, then use 25k.
  3. Aloe


    Apr 10, 2016
    Passive ones. The guitar is bright enough for me with stock electronics, so I think that 250k would be enough for volume (but I don't really know the difference, so appreciating any advice).

    I'm able to buy both 250k and 500k volume pots and experiment with them anyway, but it looks like I will have to buy the balance pot online from abroad. Is starting with a 500k balance pot a good idea or I may need a 200-250K?
  4. It's really not worth fussing over. The difference is fairly subtle. 250k will give you a better taper, but 500k will give you a slightly brighter tone.

    By the way, I would suggest that you choose an M/N taper blend, rather than an A/C taper blend, and preferably leave the ground wires off of each wafer. This gives the best performance.
    Aloe likes this.
  5. Aloe


    Apr 10, 2016
    Many thanks for you suggestions. Two more questions:
    1. How to I differentiate a M/N pot from A/C one? I'm looking for the pots online and it seems like allparts does not specify if it's M/N or A/C. The same question with a simpler answer: please recommend a M/N 250k blend pot that's available online.

    2. Err, do I get it correctly that I should not ground them? Or should I ground them, but independently?

Share This Page