Preamp killing instrument cables?

[snogaws]

Ok, so I recently got a used Eden Navigator preamp. It sounds great and works fine, however after an hour or so of playing it, my cab started producing a very disturbing crackling noise. I inspected the cabinet itself and saw no issues, so I tried a new instrument cable. The noise was gone! Thanks God, I thought. but a half hour or so later, the noise came back. I tried a third instrument cable and the noise went away again, but came back 20 minutes later. Has anyone experienced anything like this before? Is my preamp really killing the cables? Or is there another issue?

Any help would be appreciated. Thanks!

[RoboChrist]

It could be a dirty input jack. Deoxit is your friend!

Also replace the tube if the above doesn't work.

[snogaws]

Originally Posted by RoboChrist

It could be a dirty input jack. Deoxit is your friend!

Also replace the tube if the above doesn't work.

That's what my bandmate's father who is a sound guy just told me. I think that's probably it. Thanks!

[lowendgenerator]

NO! The preamp is filled with evil spirits! You must bring it to my solemn church of tone and let me exorcise the demons!

[bongomania]

Originally Posted by snogaws

Is my preamp really killing the cables? Or is there another issue?

No, and yes. There is no part of a cable that can be harmed by the output of a preamp. So it's something else.

I agree with the other guy that dirty jacks are among the very first things to check when there are "mystery noises" or signal going weak, etc. And while preamp tubes don't go bad very often, it can happen. It's also conceivable that the tube might have gotten jostled loose in transit; so I'd pull it, clean the pins carefully with steel wool, and reinsert it snugly.

[JimmyM]

Ya, the tube is the first thing I'd suspect. Fortunately, they're easy and cheap to replace if cleaning the socket and pins doesn't work.

[johnk_10]

maybe it's just me, but i wouldn't get steel wool anywhere near my amps or it's tubes. a tiny shot of deoxit on the tube's pins, or the tube socket is more than enough.

but i don't think that's the OP's problem. the first place i'd look for a symptom like that is the send & receive jacks. patch a short guitar cable to loop it and see if it does it anymore. if it's gone, then just clean the S/R jack's switches with deoxit.

[JimmyM]

Good point, John. Might be right. Most people don't use them so they tend to get corroded after a while. But I was thinking it might be a tube because it took a few minutes for it to start. Or would it start right away if it was the tube?

[johnk_10]

with a tube, it could be anything from happening immediately to happening after 20-30 minutes of warming up, but it still seems like more of a dirty S/R jack problem to me, since it's alot more common.
and again, it's NOT the cables.

[walterw]

yeah, the OP could go back to the first cable and the exact same thing would likely happen again.

+1 to steel wool around amp parts being a Bad Idea.

[B-string]

Hard STEEL------"soft" GLASS-----High Voltage-----what's the problem?

[grendle]

Originally Posted by lowendgenerator

NO! The preamp is filled with evil spirits! You must bring it to my solemn church of tone and let me exorcise the demons!

+1

[bongomania]

Originally Posted by walterw

+1 to steel wool around amp parts being a Bad Idea.

Very true that tiny fragments of steel wool can be a nightmare inside any electronic device... I withdraw my steel wool suggestion. The funny thing about it is that I actually use fine sandpaper for cleaning pins, but when I typed the post I thought that would sound silly--so I wrote steel wool! Made myself look even dopier.

I have seen a lot of tube pins (on old stock) with so much crud on them that Caig's was not enough to get them clean. An abrasive of some sort is quick, easy, and more effective.

[johnk_10]

1500 grit sandpaper is what i use when they're really bad. then i wipe them with deoxit on a q-tip