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Alembic Club » Alembic Basses & Guitars » Archive through July 26, 2013 » Series 1 preamp noise « Previous Next »

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Username: 87_persuader

Post Number: 5
Registered: 3-2005
Posted on Sunday, March 17, 2013 - 12:56 pm:   Edit Post

I think i want to send my 1976 Series 1 preamp in for testing...power supply ripple tested noise is prob in preamp. How do i go about doing a return?

Senior Member
Username: slawie

Post Number: 492
Registered: 8-2002
Posted on Sunday, March 17, 2013 - 6:29 pm:   Edit Post

Have you gone through the procedure as outlined here?
Username: 87_persuader

Post Number: 6
Registered: 3-2005
Posted on Monday, March 18, 2013 - 5:26 am:   Edit Post

The problem is alittle different; neck pickup doesn't work,bridge does...if i swap red and blue wires from preamp i get neck but no bridge. Lotta 'egg frying' noise like a bad cap sound..the square gold colored transistor on the board gets pretty warm....neck PU vol pot seems bad during sweep and the tone pot on bridge PU had broken in half...taped i have a few issues to resolve.
Senior Member
Username: jimmyj

Post Number: 438
Registered: 8-2008
Posted on Monday, March 18, 2013 - 9:22 am:   Edit Post

Sounds like it needs some help! We're all Alembic nuts in here so we'd love to see a pic and hear more about the instrument if possible.

The "square gold" component you describe could be the original "flat pack" op-amp (many pins soldered to the board). I think there were 3 of these back in the day, on the underside of the board? These can run hot when operating correctly and if two are hot and one isn't then the cold one might be dead. (I'm just making this up so wait until somebody who actually knows can confirm my theory.)

Your best bet of course would be to get the instrument to the factory for a once-over. Beyond that, they can supply you with parts, including a new preamp board and adaptors, and help you work on it. Either approach will take time, patients, and some dough... but we cheer your efforts to revive the old axe!

Tell us more!

Jimmy J
Senior Member
Username: gtrguy

Post Number: 596
Registered: 9-2004
Posted on Monday, March 18, 2013 - 10:18 am:   Edit Post

If I remember right, they have a set price to repair that board and it is quite reasonable.

If you have narrowed it down to the board, I would email Mica at Alembic.

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