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PuP cutting out

Discussion in 'Pickups & Electronics [BG]' started by Sqeejo12000, Nov 3, 2005.

  1. Sqeejo12000

    Sqeejo12000 Guest

    May 5, 2005
    Okay so everytime I am at band practice my Jazz pup on my Ibanez Sr400(active) is cutting out! :mad: It only happens after I have been playing for a while and if I put it down for like thirty minutes it starts playing again. Now the P bass Pup by the neck works fine all the time. Now my question is that I figure that I am going to need a new Pup to replace the J bass one, but I am not sure if something else would be causing the problem. I mean I even took it in to the shop where I bought it and they obviously said nothing was wrong cause they couldn't get it to duplicate the problem cause it only happens after it has been playing for a while. (And by the way it is not the battery cause I have already changed it.) Okay the question here is if it is the Pup should I get a set for both to match or just the J bass one and what brand would you recommend for a nice Dark metal tone. Lots of Dropped C songs... And if it is something else where should I start looking. Thanks in advance! :help:
  2. I would look at wiring, switches, or jacks, instead of the pickup. Passive pickups are pretty basic--some turns of wire around some metal...there's no moving components, no parts to wear out, no semiconductors to go goofy--it's just some wire. In other words, it's pretty hard for a pickup itself to fail, and even harder to fail intermittently (works most of the time, not at others).

    Check the wiring for any loose connections, possibly loose solder joints. Also see if there's any wires that could short to ground.

    Switches and pots can get corroded, causing intermittent dropouts. The contacts in a jack can get loose and corroded as well.

    I would say there's a 99 percent chance it's in a switch, pot or wiring connection, rather than the pickup itself.
  3. Sqeejo12000

    Sqeejo12000 Guest

    May 5, 2005
    Well if it is the one of the pots or switches reather than the pickups themselves, could it be isolated strictly to one pickup then more specifically only a portion of it? I tried it today again when I got home. Played for about 45 minutes and then all of a sudden it did it again but it was only on My E and A strings. D and G were fine through the same pickup and concurrently when I switched to the P bass pickup it sounded fine. Oh and it is a Blending knob which will start to blend in signal from both to only one at a time.
  4. A Jazz pickup only has two "wires", hot and ground. No matter what string you play, the signal goes through the same two wires....

    Actually to be technical, it really only has one wire, what you are seeing is the two ends of the same wire....one really long wire gets wound around the pickup bobbins, then the two ends are what gets connected to the blend pot.

    My point is, it's pretty darn difficult for that same wire to be good for one or two strings, but not for the others. After all, it's a single wire that doesn't move or anything, it just sits there inside the pickup.

    Here's the ultimate test: unsolder the pickup, then solder it directly to the output jack, bypassing everything else. Just the pickup connected directly to the jack. (Obviously this is a temporary test procedure).

    I suspect the blend pot or the wiring at the blend pot, check for a cold solder joint or an adjoining wire that may be vibrating enough to touch one of the terminals on the blend pot..
  5. Sqeejo12000

    Sqeejo12000 Guest

    May 5, 2005
    Thanks for the advise I am going to check on that tonight. It ought to be interesting to see whether or not I can find something wrong. May have to just go out and get a new Iceman bass. :D
  6. pkr2


    Apr 28, 2000
    coastal N.C.
    You are dealing with a techs nightmare. An intermitent!

    About the worst thing that you can do is to "somehow" start it to working without knowing exactly what the problem was. It will do it again and then Murphys law.

    I have found that the best way to locate a problem like that is to use the amp as a signal tracer.

    With the jack plugged in and connected to the amp turn the volume up a little and with the cover off the cavity touch the tip connector on the jack with a nail or any metal object that you can get into tight places with. You'll probably get a loud buzz from the amp. That tells you that the jack and cable are ok. Just back right through the signal path untill you lose the signal and you are at the source of the problem. If you touch the hot wire coming from the pup and you hear the buzz in the speaker, chances are that the pup is bad. To prove it, it would be best to disconnect the pup hot wire and then inject the signal into the terminal it was connected to. If you still don't get a buzz chances are that the pup is ok.

    Go to the volume pot and repeat. etc. etc.

    Give it a try. it works very well.

    You can check almost the whole circuit in just a few minutes.
  7. The pickup may be a humbucking Jazz pickup, in a stacked or side by side configuration - in which case it will have four wires (actually only two of course, but four ends).

    In a side by side humbucker Jazz pup, if one coil has a short, then only two strings (E+A or D+G) will work. If the problem is isolated to two strings, this may be the problem. If the humbucker is wired in series, any short will stop the whole pup from working, but if it's a parallel wired side by side split coil humbucking Jazz pup this could be the issue.

    I agree that a good troubleshooting approach is to wire the Jazz pup directly to the output jack and disconnect everything else. Play the bass for a while like that, and see if the problem occurs. If it does, chances are it's a pup fault.

  8. Ah, yes!!! Could be a side by side humbucker wired parallel...since it's an intermittent fault, I'd suspect the solder connections where the two sides are joined. Should be easily fixable.

    I'd still go with the direct-to-jack approach for a test, that absolutely positively rules everything else out, then if the problem still occurs, look closely at all connections in/around the pup.