Alembic Guitars Club

Alembic products => Owning an Alembic => Troubleshooting => Topic started by: ifredoto on October 02, 2009, 03:24:25 PM

Title: High Pitched Squeal
Post by: ifredoto on October 02, 2009, 03:24:25 PM

I have a 1980 LSB1 and am the orignial owner. I have gone through several 5 pin cables over the years and have recently encountered an issue. A high pitched squeal which stops when I disconnect the 5-pin cable. When I plugged it back in, it started again. This isn't the forst time this has happned. I changed to a back up cable and didn't have any issues for the remainder of the gig. I did have the module board worked on some 20 years ago and was wondering if anyone else had similar issues .Is the cable or the comdule board

Title: High Pitched Squeal
Post by: 811952 on October 02, 2009, 04:06:19 PM

turn the filter knob and see if it quits.  mine does that sometimes if the q is at maximum.
 
John

Title: High Pitched Squeal
Post by: the_mule on October 03, 2009, 12:04:05 AM

If you try John's suggestion and it seems that the problem is there, you could tweak the trimpots on the backplate for that particular pickup: http://club.alembic.com/Images/16271/50896.html?1208917987 (http://club.alembic.com/index.php?topic=273)
 
I had the same problem with the bridge pickup of my Series I with the filter and q to the max and I managed to solve it with a small adjustment of the hum balance trimpot and the pickup height.
 
Good luck!
Wilfred

Title: High Pitched Squeal
Post by: David Houck on October 03, 2009, 03:17:27 PM

- Does it always squeal with the one 5-pin cable, but never with the other?
 
- Does it squeal with a 1/4 cable?
 
- How long has this been happening?
 
- Does it squeal when the selector switch is on neck pickup ony?  Bridge pickup only?

Title: High Pitched Squeal
Post by: 811952 on October 03, 2009, 03:31:16 PM

-Does it do it on the job?
 
-Does it do it with a knob?
 
-Does is do it in a pinch?
 
-When it does it do you flinch?
 
-Does it do it over there?
 
-Does it do it in a chair?
 
;)
 
I couldn't resist.  Sorry.
 
John

Title: High Pitched Squeal
Post by: David Houck on October 03, 2009, 03:38:42 PM

Actually, it's a pretty good troubleshooting list!

Title: High Pitched Squeal
Post by: 2400wattman on October 04, 2009, 12:36:10 AM

Sounds like an application for a prostitute to me, but that's me and if anybody here KNOWS me I would think of something like this, me thinks!

Title: High Pitched Squeal
Post by: slawie on October 04, 2009, 01:09:13 AM

Wow Dr. Seuss is a club member!
 
slawie

Title: High Pitched Squeal
Post by: 811952 on October 04, 2009, 12:24:20 PM

Does he play a Series I?
 
Does he play it just for fun?
 
Does he gig with it for free?
 
Does he gig and charge a fee?
 
;)
 
John

Title: High Pitched Squeal
Post by: ifredoto on October 04, 2009, 02:46:42 PM

I have tried flipping switches and turning knobs and the only thing which will stop the noise is disconnecting the cable. It has also happened once using the 1/4 but coincidentally, the batteries went dead so after I changed the batteries, no noise.
 
I will try the trim potts as I have cleaned everything else except those.

Title: High Pitched Squeal
Post by: David Houck on October 04, 2009, 03:19:40 PM

So it happens with both five pin cables?

Title: High Pitched Squeal
Post by: 811952 on October 04, 2009, 05:00:39 PM

I might suggest re-seating the connections inside the body.  Being an older instrument, it's entirely likely that there may be oxidization that's throwing the whole mess out of specification..
 
John

Title: High Pitched Squeal
Post by: ifredoto on October 04, 2009, 05:37:35 PM

Hasn't happened with Alembic cable yet. It might be too soon to tell. I will check the trim potts and inside body connections to see if that helps.
 
Thanks for the suggestions.
Ian

Title: High Pitched Squeal
Post by: 811952 on October 04, 2009, 06:09:15 PM

That's a beautiful bass you've got there...
 
John