Gremlins

TroyK · #1 05-13-2009, 02:10 PM

I'm not sure if this goes here, because I don't really know what's going on, but since I've referenced it in a few other threads that I don't want to hijack, I thought I'd start a new one here.

At this point, I made need a luthier, I may need new cables, I may need EA and GK customer service or I may need an exorcist. (if you know anyone, let me know)

Since I don't post much in this particular forum, let me give you my vitals. Beloved Czech factory bass with a magic Jake DeVilliers set up, EA iAmp 200 combo with a GK MB150 as backup. Fishman Full Circle pickup. Curmudgeon jazz guy with a very unhealthy string fetish that is more or less under control, or at least that's what I keep telling my sponsor.

Maybe as much as a month ago, I was on a gig with my iAmp, when I started hearing a bad sound coming from it, that sounded exactly like a failed driver. I searched and posted here and found that some people had rattling screens and that their problems were resolved with strategic felt, so I pulled out the backup amp for a week or so until I got around to dealing with it. I had another bassist over a few weeks ago and had him look for the rattle while I played and play while I looked for the rattle. We ended up taking the screen off, but the rattle/clip/whatever persisted. I took this to be bad news that suggested a more serious and more expensive problem with my amp. So I wrote to Bob, who sold it to me some years ago and he referred me to EA, who were very eager to help me and asked me to ship it to them. I started looking for an appropriate box and continued going back out with my GK. Bought a box from UHaul yesterday and planned to ship it to them today.

HOWEVER, last night, I started getting almost the same sound from my GK in a rehearsal. When I turned it up, it got worse. Now I'm stressed out because both my amp and it's backup have failed drivers at the same time. Damn. The piano player, who was practicing on his electric last night uses an Roland Bass Cube and at one point he moved to his real piano, so I went through his Roland just to finish the rehearsal out and guess what, some rattle.

So, I suspected me chord, which is a few years old or my pickup. But, I unplugged the pickup entirely and got the rattle. Damn, now this is really getting bad. I couldn't isolate it, but at one point put it on the rib opposite me in the "C" part (sorry guys, not sure on the finer points of DB anatomy) and it stopped. And today I can't get it to happen. I pulled my Fender out and played it through my EA and it was clean. I'm not convinced, but I'll test both amps extensivelty and may buy a new cable, just because it's time and that cable's backup belongs in a museam.

So, I'm playing the bass today and I can't get it to rattle. Then again, I haven't been hearing it acoustically. I wondering now if my EA, which hyper hi-fidelity, just picked up what was subtle enough a month ago to go unnoticed by me or the GK. But, I did hear it briefly unplugged last night, so I think its in there and I can't amplify (which is a fundemental requirement).

What do you guys think, haunted?

I realize the only particularly good advice is "get thee to a luthier", which is advice I'm better at giving than following. Jake has worked wonders with this bass, but he lives in Canada, which is this whole other country. There is someone else who I like to use locally, but I haven't been there in a while and I suspect that she's a bit backed up. Hammond Ashley are good folks and they would probably be my best bet under the circumstances. Any advice on at least reproducing or isolating the sound? I feel like I know how to test the electronic equipment, but am not sure on the bass.

Jake deVilliers · #2 05-13-2009, 02:42 PM

Hey Troy, have you checked that the FC is firmly plugged into the extension cable? That the cable is clear all the way to the endpin?

TroyK · #3 05-13-2009, 02:50 PM

I moved it around a bit last night and then unplugged it in it's RCA connection and the rattle went on. It still possible that the cable or jack on the tailpiece wire was rattling, which could explain why it doesn't happen unplugged. I'll keep chasing it.

Troy

mikeyswood · #4 05-13-2009, 02:53 PM

I was hoping to post my love for Gizmo here....

Marcus Johnson · #5 05-13-2009, 04:12 PM

Popped seam, maybe? A small one can cause a mighty rattle. I always found mine by narrowing it down by playing and pushing down gently on the suspect part of the table. Sometimes you can find it with a thin piece of paper.... it'll slide through if the seam's popped widely enough. Other times, you can just see them, as a line in the seam's finish that just doesn't belong there.

TroyK · #6 05-13-2009, 04:28 PM

Can't find it, but I'll keep looking. I may try to find a way to shine a light up in there and see if it peaks out at a seem. It unfortunately sounds like that, but then again it sounded like a failed driver or speaker cone a few weeks ago, so I don't know.

smg_luthier · #7 05-13-2009, 04:28 PM

hey Troy,
it kinda sound to me like you might have an open seem or something, but i can't tell you from here.
obviously, (although not always 100%), if you play that bass through a certain rig with a certain cable, and it rattles, and then you change basses, and play through the same rig with the same cable, and there is no rattle, then ther must be something wrong with the first bass. (is first bass under the shirt over the bra, or just kissing??)
try to eliminate the least expensive variables first.
if you have an other pickup layin' around, or if you can borrow one for a day or two, try that.
if you have an other set of strings handy, try that.
check your endpin. sometimes if the lock screw is just a little loose, or if there is too much rod inside the bass, or the most elusive of all gremlins, a loose rivot or cotter pin at the end of the rod. of course, if you go to change your strings, that's when you'll want to check the endpin.
again, i really can't help you from here, just trying to point out some of the simple things that we tend to overlook when something is such a major headache.
also, just try playing it acoustically in a quiet room, and see if you can zero in on anything. sometimes you just need to hear where it's coming from.
hope this might be of some help.
smg.

Marcus Johnson · #8 05-14-2009, 06:34 PM

Quote:

Originally Posted by TroyK

Can't find it, but I'll keep looking. I may try to find a way to shine a light up in there and see if it peaks out at a seem. It unfortunately sounds like that, but then again it sounded like a failed driver or speaker cone a few weeks ago, so I don't know.

That's usually pretty minor work... I have a real nice girl who comes over and glues 'em up for me at my house, so she doesn't have my bass laying around in her shop. She's cute, too.

Uncletoad · #9 05-14-2009, 09:52 PM

Sounds like an open seam to me too. Very common and annoying.

Usually you have to open them up more than they are to get them glued up properly. Sometimes it takes several trys to get it all. I've still got a leak in the Cleveland that I have yet to take more time to chase down. Hit that right note and it's ugly sounding.