1. Welcome to TalkBass 2014! If you're new here, we just went through a major site upgrade. Please post all concerns and bugs to the Forum Usage Issues forum. We will be monitoring that forum. Thank you for all of your feedback.

    The TB Android app is working, you may need to uninstall/reinstall. The iPhone app is now updated and should work after you upgrade. TalkBass is responsive to any screen size, so we recommend using your mobile browser for full functionality.

    Please read the TalkBass 2014 FAQ for lots of great info on the new software.

Potentiometer advice :: 250k vs 500k

Discussion in 'Pickups & Electronics [BG]' started by poit57, Jan 31, 2014.

  1. poit57

    poit57

    Joined:
    Apr 30, 2010
    Likes Received:
    0
    I am working on a Cimar by Ibanez P/J bass that has a scratchy pot on the P pickup volume. As I was going to change out the volume pot, I discovered that the pots used are 500k, but the wiring diagrams for P/J configuration that I've found all recommend 250k. I have a few of those lying around, but I would have to order a 500k to match the stock specs. My gut tells me to just use the 250k pots that I have since that seems to be the insustry norm for this pickup configuration.

    Is there any reason why I might want to stay with a 500k other than the fact that this is how it came from the factory?
  2. tylerwylie

    tylerwylie Supporting Member

    Joined:
    Jan 5, 2008
    Likes Received:
    3
    500K will let more top end come through. If you want a brighter sound, this is the way to go.
  3. uOpt

    uOpt Supporting Member

    Joined:
    Jul 21, 2008
    Likes Received:
    0
    For the tone pot, if you turn down a 500 Kohm pot to where it reads 250 Kohm on a meter it is the same thing as having 250 Kohm in the first place. Same trick doesn't work with the volume pot.

    I have a precision configured with 250 Kohm volume and 500 Kohm tone for that reason. More flexibility. Whether the extra top end is useful or nor depends mainly on - the strings :)
  4. friedtransistor

    friedtransistor

    Joined:
    Dec 9, 2013
    Likes Received:
    0
    I would stick with the 500k. You'll lose less signal then. Personally, I've been meaning to get some 1M's for my instrument... Also, with a higher resistance, you'll hear more of the raw pickup tone, and so you'll have a wider range of frequencies to shape. But your cable will be more of a factor in the tone then. Could someone else varify that, please? I work with RC circuits, so I have little experience with LC designs, and zilch with RLC circuits.
  5. poit57

    poit57

    Joined:
    Apr 30, 2010
    Likes Received:
    0
    Thanks, guys. The owner of the bass fills in for me at church when I'm gone, but he normally plays guitar. I think he only got this bass so he would be able to cover bass when we need someone, but he has pretty much neglected the quality of sound in this bass. It stays up at the church all the time, so I borrowed it for practice a few nights ago when I didn't have my bass with me and discovered how poor the setup was, if it had actually had a setup done at all. All the string saddles were as low as they could be causing terrible fret buzz on the E string and it was not intonated correctly.

    I'm working on this bass partially because I want a playable instrument in the rare cases that I ever do borrow this bass (for rehearsal if anything). I'm also doing this because when the other guy does play in front of the church with this bass, I don't want the sound quality to suffer because of these issues.
  6. pfox14

    pfox14

    Joined:
    Dec 22, 2013
    Likes Received:
    1
    My understanding is you should use 250K pots for single coil pups and 500K pots for humbuckers. Also, a scratchy pot can be easily remedied with some pot cleaner.
  7. poit57

    poit57

    Joined:
    Apr 30, 2010
    Likes Received:
    0
    I've read that too. That's part of the reason I was asking for advice since this bass came stock with 500k pots and single coil pickups.

    From what I've read, this offers only a temporary solution and it is better in the long term to go ahead and replace the pot. It's not that difficult, so I figured I might as well replace them.
  8. Chainsaw Willie

    Chainsaw Willie

    Joined:
    Nov 6, 2011
    Likes Received:
    0
    I have replaced 250k tone pots with 500k and I like 500k better. As another posted, the 500k pot allows you to roll it up to a brighter tone while still being able to roll it down if you want. Since the tone pots are wired as a simple variable resistor (unlike a volume pot wired as a voltage divider) there is a 250k setting on a 500K pot, but you cannot roll a 250k pot to 500k ohms.

    A 250k pot will cut more treble when set to 10 than a 500k will at 10.

    If the instrument originally came with a 500k pot, and you normally play with it set to 10, replacing it with a 250k pot will make it sound like the old tone pot did when set to 5.
  9. Chainsaw Willie

    Chainsaw Willie

    Joined:
    Nov 6, 2011
    Likes Received:
    0
    And crap, I just re-read the first post and realized you are changing the volume pot and not the tone... Doh!

    I vote for pot cleaner/lube spray and see if "temporary" doesn't mean 10 years. Even good quality pots can get dust under the wiper.
  10. Dogghouse

    Dogghouse

    Joined:
    Jan 25, 2011
    Likes Received:
    1
    Disclosures:
    Bass Guy @ Seymour Duncan
    What they said.....

Share This Page