Sudden pickup failure...pretty sure it's not the battery.

JasonKain · #1 12-24-2008, 10:43 PM

Update: Turns out it was the preamp. Later post covers details.

I recently picked up an ESP B5-E, which came with active pickups. Pulled it out of the box, let it sit for a few hours, plugged it into my amp. No sound. Figured the stock 9volt was dead, plugged a new one in. No sound. Talk to a guitar tech, who suggests over the phone the connection to the battery may just be loose, and crimping it down should fix the problem. I do this, and it works wonderfully. This lasts a couple weeks, until I drop it off for a general setup/restringing.

I get it back, and plug it in. Sounds beautiful, just what I wanted out of it. Approx. 3 minutes later, my amp's output drops like a stone, going from normal volume to nothing in about three seconds, followed by a small pop. Then I have nothing. I change the battery, nothing. To make sure it's not the amp, I plug my passive bass into it using the same settings and cables, and it sounds great. I checked the wiring, and every connection seems solid and every wire seems intact. I do one last check, and my dad says he hears something from the amp(he was closer than I was). I walk over, and sure enough, it's emitting a barely audible, very thin, very squeaky version of the notes I'm playing.

Due to a relative lack of funds, I'm hesitating to take it into the guitar tech if it's something I could solve with a little time. However, this is my first run in with active electronics and I don't want to bungle anything and make it worse. Does anyone have any idea as to what could have happened or what needs to be done to fix it?

Thanks for any help.

bongomania · #2 12-24-2008, 11:13 PM

Well not knowing exactly what you meant by "crimping down" the battery, if all you did was pressed a loose connection together then it was bound to come apart in short order. Solder it, and I bet your sound comes back.

JasonKain · #3 12-24-2008, 11:46 PM

Quote:

Originally Posted by bongomania

Well not knowing exactly what you meant by "crimping down" the battery, if all you did was pressed a loose connection together then it was bound to come apart in short order. Solder it, and I bet your sound comes back.

Apologies for being unclear. All I meant was I pressed together the connector on the clip that goes over the positive side of the battery. I didn't think it would be that, as when the incident occurred, the connection from the clip to the battery was still tight.

If it is something wrong with the connectors, would I be best off just getting a new clip and replacing the clip currently in the bass?

bongomania · #4 12-24-2008, 11:55 PM

Worth a try at least. Those battery-snap connectors and their wires are notoriously flimsy, and far easier to replace than to "fix".

Caca de Kick · #5 12-25-2008, 12:06 AM

I don't know where your battery sits in this particular bass. But if all you have to do is remove the rear control cover to access the battery, then leave the cover off while holding the battery and connector together, and pluck some strings with your free hand see if it makes noise.
I guess while you're in there looking around, make sure the endpin or any wires at the output jack are broken.

Kitsapbass · #6 12-25-2008, 02:11 AM

I think those 9V plug connectors are like $3 at Radio Shack...it's been a while since I've gone though, but they are readily available.

Something else that fails a LOT (at least on me anyways) are the barrel jacks/stereo output jacks. In the last 20 years that I've had basses that use these jacks, I've had to replace 9 of them. I highly recommend getting one for an emergency (as in, it fails why you are soundchecking for a gig - yes, that happened to me in real life, thank God for back up basses).

SGD Lutherie · #7 12-25-2008, 08:15 PM

Quote:

Originally Posted by Kitsapbass

Something else that fails a LOT (at least on me anyways) are the barrel jacks/stereo output jacks. In the last 20 years that I've had basses that use these jacks, I've had to replace 9 of them. I highly recommend getting one for an emergency (as in, it fails why you are soundchecking for a gig - yes, that happened to me in real life, thank God for back up basses).

I was going to suggest the same thing. If the bass has a panel (barrel) jack, that's likely the problem. If it's a regular type of jack, check that out too. Sometimes they get dirty or bent and wont work right. Since the jack is turning on the battery, that's one of the first places to look.

I'd also replace the battery clip, and then check all the wiring out.

JasonKain · #8 01-03-2009, 02:22 AM

Well, got a call from the repair shop I dropped it off at. Turns out all the connections were good, except the pots were put in sloppy. When I turned the knobs, the housings would turn just a slight bit with them. With all the fiddling I did, and not noticing the problem, apparently the solder points connected and shorted something. The tech looking at it said he was 95% sure it was the preamp, but he wouldn't be sure until another guy got in to do a test he wasn't positive on how to do. He also couldn't check the actual preamp, as it was sealed in a block of epoxy to prevent anyone from copying it. He also told me that due to how I described losing the signal, it pointed to the preamp being wired to the volume and shorting, but there was still a small chance it was the pickups.

Now, if it is the pickups, I already know what I'd like to get for replacements. On the more likely side of it being the preamp, I have no idea what I'm doing. I've heard good things about EMG and Bartolini, but I have no experience. My bass is currently set up with vol/blend/3-band EQ. I'd like to keep the 3-band, or at least something with mid and treble control. Bass I'm less concerned with, as I'm pretty happy with the bass the instrument puts out without playing with that section of the EQ.

The tech also said that if the stock pickups could function passive, it might be able to be wired so the volume and blend are wired separate from the preamp, so if the battery dies or the preamp shorts, I'd lose the EQ, but I'd still be able to play the bass. If that's the case, do I need to look for something specific?

Thanks for all the help. You guys have been guiding me a lot in the past few months.

Kitsapbass · #9 01-03-2009, 10:30 AM

you could basically run the pickup direct to the output jack...no pots whatsoever. just connect the black leads to one side of the jack, with the red leads going to the other.

As far as replacement pickups go, did you want to go active pickups, active pickups with active eq, passive pickups with active eq, passive pickups with passive eq...? There is a whole world of electronics you can go for, so it's really up to you. I will state for the record, that you can't run the normal EMGs passive, they are active pickups. If you want passive, you would have to pick up the HZs, and they tend to have a bad rap on TB...