1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  
     
    TalkBass.com has been uniting the low end since 1998.  Join us! :)

Volume knob doesn't work until full open?

Discussion in 'Pickups & Electronics [BG]' started by organworthyplayer337, Apr 18, 2017.


  1. organworthyplayer337

    organworthyplayer337 Professional Hack

    Oct 28, 2014
    Charlotte, NC
    Hi,

    My volume knob stays at a pretty low volume until it's full open...

    I talked to the tech and he said it could just be a bad pot. But could it be a wiring or ground issue? Maybe something with the capacitor?

    ***okay so I had the mixed up but something still sounds wrong.

    Please help!

    Thanks!
     
    Last edited: Apr 18, 2017
  2. Growlmonkee

    Growlmonkee

    Jan 30, 2013
    Florida, U.S.
    It's probably a bad pot, but, if you want more usable sweep, for controlling volume, a linear pot will actually do that (have a wider usable sweep), compared to an audio pot, just don't use a linear for tone, they don't work well there.
     
  3. You have that backwards. Linear taper volume pots work smoothly, while audio taper pots are prone to volume jumps.

    In any case, start by checking your wiring.
     
  4. Coolhandjjl

    Coolhandjjl

    Oct 13, 2010
    Appleton
    A linear pot in the vol position will not behave like that.
     
    organworthyplayer337 likes this.
  5. organworthyplayer337

    organworthyplayer337 Professional Hack

    Oct 28, 2014
    Charlotte, NC
    So even if it is an audio pot, should it stay at the exact same level until full open?
     
  6. No. Unless you have a bad pot, or one with a really poor taper.
     
  7. organworthyplayer337

    organworthyplayer337 Professional Hack

    Oct 28, 2014
    Charlotte, NC
    Would should I check for?
     
  8. organworthyplayer337

    organworthyplayer337 Professional Hack

    Oct 28, 2014
    Charlotte, NC
    Unfortunately, it's basically impossible to find a linear stacked pot :( but I heard fender uses audio for both volume and tone. I have a couple Fenders and none of them seem to do this. All of them have a satisfactory and usable taper..
     
    Lvjoebass likes this.
  9. Growlmonkee

    Growlmonkee

    Jan 30, 2013
    Florida, U.S.
    You most likely have a bad pot, however.....in this pic, the line showing linear taper applies to all linear taper pots, the line showing audio, (the curve), could be any curve, so it's not as defined, the taper may vary, normally a known good curve would be used in a bass, or guitar, and might vary slightly, depending on manufacturer's choice, but should be in the "ballpark" of what works well for the application. It's possible to make a pot with a taper that performs poorly for use in a bass, or guitar, since the "taper" isn't "written in stone", and ..you may have one, (it's one possibility). Our ears do not hear in a "linear" way, but, still a linear pot works well for a volume control, probably better, than a audio (logarithmic) taper pot. You're right, linear stacked pots such as 250k/250k are not easy to find, a good audio stacked pot should still give you usable control, Fender does use only audio, and they work fine. AudioTaper.
     
  10. Remember that a true log curve is expensive to manufacture, so a lot of pots are made by joining two linear segments in an approximation of a log curve. Sometimes the taper turns out decent, and sometimes it is terrible.

    pots-f4.
     
  11. Growlmonkee

    Growlmonkee

    Jan 30, 2013
    Florida, U.S.
    I did not know that Line6man, but, it explains why I've used some no-name pots over the years, (like using 3, and having to change all 3, as they were useless...then wondering why.)....now I have more of an idea why.
     
  12. Lvjoebass

    Lvjoebass

    Jan 19, 2017
    Is your knob on tight? I have never had this problem in over 40 years!
     
  13. iamprowla

    iamprowla

    Nov 28, 2016
    UK
    My first thought was is it a linear pot instead of log/audio.

    The other options are that it's a duff one or it needs a clean.

    I suppose a further one is a loose wire or nut, but if a tech has had a look at it then he should've spotted that straight off.

    A pot costs a fiver, so not a big deal to replace; CTS are a good brand and use an "A" (Audio/log) one.
     
  14. Nickweissmusic

    Nickweissmusic Knows all intervals from one Fred, to Juan octave Supporting Member Commercial User

    Jan 26, 2014
    San Diego, CA
    I teach lessons and perform live music in and around San Diego CA. Sometimes I even make money doing it!
    Definitely not normal, time to replace it. A good quality audio taper pot is fine. It's a matter of personal preference, but I always use audio taper if I'm rewiring. Anytime I play a Gibson or something with linear pots I feel like I'm turning a giant bus steering wheel to make adjustments. Ok, I'm exaggerating a little, but it does actually feel weird to me, I'm just used to audio taper.
     
  15. organworthyplayer337

    organworthyplayer337 Professional Hack

    Oct 28, 2014
    Charlotte, NC
    I think the tech may have gooched something :cautious:

    can this be a symptom of over heating?
     
  16. Spidey2112

    Spidey2112

    Aug 3, 2016
    When did this start happening? From the moment you owned it, or recently?
     
    Michael Schreiber likes this.
  17. organworthyplayer337

    organworthyplayer337 Professional Hack

    Oct 28, 2014
    Charlotte, NC
    Recently. I had a stacked volume pot installed yesterday and that's the one with the problem.
     
    Michael Schreiber likes this.
  18. What type of bass or more specifically, type of pickup system? I recently rewired a P bass from scratch. New pickups, knobs, jack and capacitor, all good stuff replacing the MiM stuff in it (*). Originally used audio taper for both pots, but volume was as you describe. I switched it to linear and now I like it. Strange because typically audio taper is always used for both, but the linear taper definitely works better for me. I am talking the volume pot, not the tone pot.

    * footnote: the answer to this guy's real question (Are the pickups essentially what give a bass its sound?) is yes, changing the pickups makes a huge difference in sound. At least for my MiM P bass.
     
  19. big_fundamental

    big_fundamental

    Oct 3, 2016
    Same experience as Headwind here. Built 2 Jazz basses using Fender-branded CTS 250k Audio pots. 90% of the volume comes in the last 10% of the knob turn. It would be easier to have a single three-way switch for bridge, both, or neck. Planning to re-do with linear vol pots for more subtle blending at some point.
     
  20. George Himmel

    George Himmel

    May 16, 2009
    The east coast?
    Former Manager, Bass San Diego
    It's been said a bunch of times by people who are right and more detailed in their diagnoses, but in the order of supporting the best actionable opinion:

    It's just a bad pot 90% of the time with this. Especially if it's a mini pot. Replace it for the cheapest trial-and-error check you can do :thumbsup::bassist:
     
    organworthyplayer337 likes this.