Yamaha BB300 Potentiometer

Discussion in 'Pickups & Electronics [BG]' started by Marclen, Jul 10, 2013.

  1. Marclen


    Jul 10, 2013
    I ran a couple searches in this section to see if anyone else had already asked. I also googled but I don't see any real results.

    I broke my BB300 volume potentiometer 2 weeks ago, how could I determine the specifications of it in order to replace it?
    Or would any of you happen to know the specs?

    Some assistance/advice would be great, thanks in advance
  2. iiipopes

    iiipopes Supporting Member

    May 4, 2009
    If you want more of a traditional P tone, get a 250kohm pot. If you want a little more edge when using round wounds, get a 500kohm pot.
  3. Marclen


    Jul 10, 2013
    Thanks for the feedback.

    A couple questions. If it was originally a 250kohm pot, and I replace it with a 500, would that cause a problem?

    Also, does it matter if the tone pot is 250 or 500kohm? or can the volume and tone pots have different kohm ratingst?
  4. Higher resistances give brighter tone, because there is less loading on the signal. It's a subtle difference, however. People make way too much of choosing values.
  5. Marclen


    Jul 10, 2013
    So I pulled the back cover off to get a look at the pot, and engraved on it was "Noble 15 A250Kohm" as well as 2 other characters I couldn't really make out. I'm gonna post a picture to see if anyone else could tell me what it is or if it's important.

    After some research, I discovered that it means that it's a 250k ohm Audio Taper pot.




    That's the last 2 characters that I can't see
  6. Marclen


    Jul 10, 2013
    Thanks for the reply. It seems slightly trivial to me as well, so I'm just gonna replace i with a pot of the same value....I liked how the bass sounded to me in the first place any way.
  7. Marclen


    Jul 10, 2013
    I was going to purchase the pot at this link because it looked almost exactly like th one in my BB300:

    but upon having a closer look I realise that the shaft is considerably shorter than mine....So I looked a little further and found this one:

    you guys think this will be fine?
  8. If you don't mind the lower rotational inertia of mini pots, then that's fine.

    Something to pay attention to is the fact that the cheap pots you are looking at may have poor tapers. Get a high quality pot. They aren't that expensive.
  9. Marclen


    Jul 10, 2013
    You mean like Fender or CTS?
    Which brands should I look for?
  10. iiipopes

    iiipopes Supporting Member

    May 4, 2009
    I am a CTS fan.
  11. Marclen


    Jul 10, 2013
    I been reading that fans are increasingly falling out of love with CTS because they're being made in China now.
    When's the last you bought a CTS pot?
  12. Marclen


    Jul 10, 2013
    Well I called around here in Jamaica (where I live) to see if anyone had, the 6th place I called had just 1 left so I went and got it. It would've taken weeks for me to receive one if I had bought it fro Amazon/Ebay, so I just decided to go for it. It was just the equivalent of $4 US anyway.

    Here it is!:
  13. Marclen


    Jul 10, 2013
    Here it is beside the old one, after I prepped it for installation. (used the same soldering points)
    (new one on the right)


    The soldering on the old one looks like that because it kinda dripped after I melted it off. Luckily I had some newspaper on top of the guitar while doing so.
    With that said though......please forgive my soldering ability.....i'm a huge novice lol
  14. Marclen


    Jul 10, 2013
    Here it is again beside the old one (the new one on the right)
    It's a little bit longer as you can see here, so it's not a perfect fit, and it is slightly raised off the guitar now after installing it.

  15. Marclen


    Jul 10, 2013
    Now that i've replaced the faulty volume pot everything is fine. The only issue is that there's a little buzz when I turn the tone up....so one of the wires leading to the tone from the volume isn't making proper contact. I'll fix that another time. It's late and I'm tired lol.

    Thanks for all the help guys
  16. Marclen


    Jul 10, 2013
    Just out of curiosity I decided to take the old pot apart. Here's what I found :(


    It literally came out in pieces in my hand
  17. Bowe


    Apr 1, 2013
    Just as an FYI, Yamaha is very good about publishing their service manuals.
  18. Marclen


    Jul 10, 2013
    Thanks, I saw one for the BB400 on their website, but none for mine. It didn't have any wiring diagrams though
  19. Musiclogic

    Musiclogic Commercial User

    Aug 6, 2005
    Southwest Michigan
    Owner/Builder: HJC Customs USA, The Cool Lute, C G O
    Bourns pot from amplifiedparts.com will be your best bet, they cost about $5 each and that includes shipping to your door....you can get them on Amazon also, just search "Bourns 250K pot"
  20. Marclen


    Jul 10, 2013
    I would've probably gone with that if I hadn't got one already.

    On another note! I plugged the bass in the morning after, and the buzz was completely gone. I'm so confused lol

    The tone and volume pots both still work perfectly fine.