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Username: evilgus

Post Number: 9
Registered: 7-2005
Posted on Tuesday, August 02, 2005 - 4:17 pm:   Edit Post

Hey folks,

Is it normal (for an Alembic bass) to be able to get your amp/rig to feedback easily by holding the bass close to the speakers? Are the pickups more sensitive or have better dynamic range, therefore making it easier? I've found that if my Epic is about a foot away from my rig and I boost the treble control even a tad, I get full-blown ear-piercing feedback. It could easily be a problem with my Eden Metro, it's currently in the workshop getting a dry solder problem fixed.


Senior Member
Username: bracheen

Post Number: 783
Registered: 11-2003
Posted on Wednesday, August 03, 2005 - 8:52 am:   Edit Post

I have an Epic that I play through a Hartke amp and 2x10 cabinet, I think the Metro is a 2x10. My bass has never produced feedback and I practice sitting almost directly in front of the rig. My tuner is rack mounted so when I use it I'm facing the speakers. I don't think it's the bass. Good luck with the solution.

Advanced Member
Username: dannobasso

Post Number: 293
Registered: 3-2004
Posted on Wednesday, August 03, 2005 - 9:05 am:   Edit Post

I blew the horn fuse in an acme 210 when i was reaching around and adjusting the controls on the cab. The bass was right up against the cab for a split second and the feedback was enough to pop the fuse (tailight bulb). I've never had that problem when facing away from the cabinet. And believe me bruddah, I play LOUD.
Username: dfung60

Post Number: 92
Registered: 5-2002
Posted on Thursday, August 04, 2005 - 10:11 pm:   Edit Post

Are you talking about high-pitched feedback? Sounds like it if you have sensitivity to the treble control.

It's unlikely that your pickups are microphonic (Alembic stuff is potted to prevent this), but that's often the cause of a whistle like this. Easy way to check is to see if it does it with both pickups - much more likely that one pickup is defective than both of them.

If the problem is on both of the pickups, then it may be electrical feedback, which could be a problem in amp or bass. If you're having amp problems, of course, it's more likely to be there. Typically some component is out of spec and causes there to be way too much gain outside the normal bass range. I guess it's actually more likely that this sort of problem might show up after your amp is fixed if the tech didn't have the exact part or was unable to do the full calibration.

It's possible that it's just regular old feedback, but it would have to be so loud for this to happen (especially at high pitch with bass speakers) that it just seems there must be something wrong.

David Fung

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