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Symptoms of a fading onboard preamp battery?

Discussion in 'Basses [BG]' started by secretdonkey, Apr 3, 2003.

  1. secretdonkey


    Oct 9, 2002
    Austin, TX
    This question is esentially a duplicate of a question I posted earlier today (thread title = Questions for Cirrus Owners). Based on some info I got since the original posting, I thought I'd ask this similar but more general question, rather than limit myself to just the Cirrus crowd:

    What sort of odd, dysfunctional things can happen when you've got dying preamp batteries?

    I bought a new Cirrus yesterday, and brought it back to the store today because it would intermittently make a horrific and full-signal static-crackle-pop. The store says that fresh batteries have cured the problem.

    I hope they are right - but having never had a preamp of this sort, I would assume that a dying battery(s) would tend to give a distorted fuzz, but in a weak and dying tone sort of way. The fact that my noise is so loud and angry makes me suspect. I'll get to figure it out soon enough, but I've got a tight schedule over the next few days and my next chance to really get some playing time will be a gig on Saturday - it's gonna suck if I take my new baby on stage and she loudly craps out in the middle of a song!

    Anyway, any thoughts on this issue are appreciated.

  2. Ben Mishler

    Ben Mishler

    Jan 22, 2003
    San Jose
    One time at band pratice I got this terrible sound that was super distorted, to the point where I could not even distinguish the notes I was playing. When I put in a new battery, the problem went away. I had never heard of this problem before, and I assume that it was the battery.
  3. mikezimmerman

    mikezimmerman Supporting Member

    Apr 29, 2001
    Omaha, Nebraska
    Different preamps behave differently. Usually, you just hear the signal starting to distort as the battery gets low, but on some of my basses I've heard crackles and fading signals, ear-piercing squeals (I thought the amp was blowing up!) and other strange noises.

  4. I guess different basses respond differently depending upon how their preamp is designed. My Ibanez Musician starts to loose volume and it will also start to sound like the patch cord is shorting out. I've never run my Stingray down, but, EB says the bass will loose volume and may sound distorted.
    Pretty much the same deal as the Ibanez.

    My Zoom 506II pedal will loose volume and it'll have no dynamics at all.

  5. Bad input jack, Dude.
  6. secretdonkey


    Oct 9, 2002
    Austin, TX
    So far, fresh batteries seem to be doing the trick... the fresh batteries also give a hotter, cleaner output and change the sound a bit, too.

    Input jack was one of the first thing I checked, btw - it certainly sounded like a short there - good suggestion.

    Thanks all for the replies!

  7. wulf


    Apr 11, 2002
    Oxford, UK
    Over the past month or so, I'd been noticing that my Sei was generating a lot of 'background interference' unless I panned all the way to the neck pickup. The tone and volume were fine, but there was a lot of random noise in the background, which was made much more audible if I plugged into any kind of external unit (eg Zoom multi-FX or Sansamp Bass Driver DI).

    I was a bit mystified, particularly because the neck PU was fine but any hint of the bridge PU and the noise appeared. I was also a bit concerned, in case it was some kind of problem with the wiring.

    However, I finally got round to popping a new battery in on Sunday and, c'est voila, instant cure. Therefore, for any kind of wierd sounds, putting in a fresh battery might be a good first step.

    BTW, the PUs are Barts and I think the preamp is also Bartolini. Whatever, I might enquire if it would be possible to fit an active / passive switch just in case I get caught without a fresh battery...

  8. Brad Johnson

    Brad Johnson Supporting Member

    Mar 8, 2000
    Gaithersburg, Md
    DR Strings
    Shouldn't be a big deal. You could replace your volume control with a push-pull pot.

    I have an old Tobias with 3 9v batteries (two for the pre, one for the pickups). Great sounding bass. Whenever it started sounding even better, I knew the batteries were starting to fail. I thought about adding a pot to drop the voltage, just to get that extra growl all the time;)
  9. Fuzzbass

    Fuzzbass P5 with overdrive Gold Supporting Member

    LOL, I thought about doing that with an old FrankenPJ of mine: the Furman parametric preamp added excellent grungy growl when the battery was low. But my tech looked at me funny when I asked if he could install a voltage regulator, so I decided not to pursue it.
  10. Sundogue


    Apr 26, 2001
    Wausau, WI
    The symptoms you experienced is exactly what happens when the Cirrus on-board preamp batteries start going dead. I know...I own a Cirrus.

    I write the date on a piece of tape and put it right on the battery compartment cover, so I know when to change them.

    A good set of new alkalines last me about 3 months.
  11. i had the same problem with my Cirrus. I'm just really glad that all it was/is was a battery problem rather than a preamp problem.
  12. I tend to replace my batteries if my Yamaha loses its "roundness" even if I put my bass boost all the way. I like the growl of a dying pre amp though:D

    So you cut your voltage to get that growling sound you say...:meh:
  13. Fliptrique


    Jul 22, 2002
    Szczecin, Poland
    Endorsing Artist: Mayones Guitars&Basses
    When my battery is weak, the bass losses dynamics, when it`s almost dead I get a disorted sound. AFAIR heavy metal guitarist often use almost dead batteries in their distortion boxes...
  14. ttyR2


    Feb 23, 2003
    Athena, OR
    Sounds like a new market. 6V batteries in a 9V package.
  15. Sorry to bring back an old thread, but my Spector Q4 seems to be having the same problem where it makes a loud popping and hissing through the amp. I tried replacing the battery and the problem did not go away, so I'd like to investigate the idea of a bad input jack. If this is the case, what can be done to fix it(I recently bought the bass and would still be able to return it if this is a major problem.) Any suggestions are greatly appreciated. Thanks.
  16. Eyescream


    Feb 4, 2004
    Knoxville, TN
    Check the wiring going to the input jack in the control cavity. Likely either the wires are broken, the solder joints are bad, or the jack itself is old and won't contact the cable end very well anymore (this is the easiest, just bend the little metal tab so that it contacts the cable better). All of these are an easy fix, comparatively speaking. I had to do that on my old pre-lawsuit Ibanez guitar. If bending that metal tab doesn't work, it's usually just a case of heating up the solder joints and fixing the little cracks in the solder.

    I probably don't have to tell you this, but for the sake of posterity I'm gonna post it anyway: Do remember to take the battery(ies) out of the bass and disconnect the cable from your amplifiers and the bass before you start digging around inside the control cavity.

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