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Username: tybeert

Post Number: 2
Registered: 10-2012
Posted on Thursday, October 25, 2012 - 6:59 am:   Edit Post

My neck pickup Q is really squeaky when I sweep it back and forth. Sometimes making a very loud "blip" -- it also seems that it's contouring quality cuts in and out. So, after I sweep it around a bit, it squeaks, and comes back into functioning properly. Is the Q going bad? Do I just need to exercise it?

A separate issue...if I buy a stereo to mono cable for the 1/4 inch out (running on the 9V in the back), will I get both pickups? Many thanks!
Senior Member
Username: jimmyj

Post Number: 413
Registered: 8-2008
Posted on Thursday, October 25, 2012 - 9:02 am:   Edit Post

Hey Joel,

Welcome to the forum. Yes the story is that even sealed pots and switches need to be exercised to properly function, especially on gear of this vintage. The recommendation is something like 50 cycles of a switch and 50 full sweeps of a knob (do it with the amp off so you don't send any crazy audio spikes down the line). That should refresh the electrical contacts of those components and bring them back to proper functionality.

The simple answer to the stereo to mono question is that you need a couple small resistors to "sum" the two outputs together, you shouldn't just link them directly to each other. The Series basses now come with a mono 1/4" jack your '76 can be modified to have that. The full info is in other threads here, like this:

Lastly, we all love to see pics of old Alembics so if you get the chance please post a couple.

Jimmy J
Username: tybeert

Post Number: 3
Registered: 10-2012
Posted on Thursday, October 25, 2012 - 10:34 am:   Edit Post

Thanks Jimmy! I'll post a few pics soon after I clean the bass up a bit. It's my primary working bass. I have a DS-5 that needs some work. The unit unfortunately took a fall when I moved earlier this year and fouled the mono/stereo switch. I hope it's an easy fix. The bass has a few dings (patina ;-) ) from the years, but it's wonderful to play and still looks great.
Username: vincebus

Post Number: 4
Registered: 1-2011
Posted on Monday, October 29, 2012 - 12:15 pm:   Edit Post

My 76 still squeaks not nearly as much as it use to. It sat idle 20 years after I started playing again it took hundreds of "sweeps" to go away.
Senior Member
Username: elwoodblue

Post Number: 1465
Registered: 6-2002
Posted on Wednesday, October 31, 2012 - 8:56 am:   Edit Post

I have a pot in an activator set-up that has gone doesn't have stops anymore.

I know that "blip" you speak of , it is LOUD.
(I always get a good rise out of my band members, they never seem to remember what makes the noise ... LOL ).
Senior Member
Username: gtrguy

Post Number: 522
Registered: 9-2004
Posted on Thursday, November 01, 2012 - 11:19 am:   Edit Post

Oh yeah, the famous disappearing pot stops. I have taken a couple apart and they are plastic nubs that wear off and there is no way to fix them. They do usually keep working though, but just will not stop 'on the dime' at the end of the travel where they should.

Expensive to replace and sometimes hard to find, as they are usually ordered off a spec sheet that has about 400 options and a minimum order of 500, or something like that.
Senior Member
Username: gtrguy

Post Number: 523
Registered: 9-2004
Posted on Thursday, November 01, 2012 - 11:20 am:   Edit Post

Of course, the Mother Ship has them in stock!!

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