Alembic Guitars Club
Alembic products => Owning an Alembic => Troubleshooting => Topic started by: jpreysen on August 08, 2006, 08:55:48 PM
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I've got a '95 Epic (as I'm sure many of you can relate, it's my baby!). It hadn't been set-up in quite a while (and for the time being I still don't trust myself balancing the double truss rod). I took it to get worked on by somebody who came with very high credentials who is in town just one afternoon a week.
To make a long story short, the next day I picked up my bass, got home, put some new strings on it, plugged it in...... and nothing. OK, just the battery right? Changed it with one I found around the house........ nothing. Went and bought a new one.... still nothing. Checked all the connections to the pots. Everything seems connected as it should be.
One thing I did notice though. When I brought the bass in, the volume knob was a little loose. Now it seems tighter, but I can tell that at least the knob was taken off (it now has a different starting and stopping locations).
Just wondering if any of you had any insight or ideas. I can't talk to the tech until Thursday afternoon, and honestly I don't want him laying another finger on it (even the set-up doesn't feel that nice!). Considering I live in CA, I figure I might just make an appointment and drive the 4-5 hours to get it looked at by the kind folks at Alembic. Just wondered if I'm overlooking anything, or if any of you had any suggestions.
Thanks a bunch,
Pete Reysen
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Sounds like one of the terminals on the volume pot might be touching the shielding paint inside the cavity. Since the shielding paint is used for earth as well, the terminal would short out the signal.
You can get some funny noises if the pots are not sitting snug.
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Pete, if you can, take a closeup digital picture of the control cavity and post it on this thread. It's not unheard of to have club members spot problems from pics.
Rich
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Pete:
Welcome to the club. It sounds like your problem is probably minor. I suspect with the above advice you should be able to figure this out pretty easily. Once you do, don't be so afraid to lay your own hands upon the bass. Alembics are designed so that you can easily make the necessary adjustments. Step by step instructions can be found in the FAQ & Must Reads section of the forum. As for the trip to Alembic, I encourage you to make the pilgrimage, even if you get your bass figured out and set up. You can actually make it from Fresno to Santa Rosa in less than 4 hours (no stops and left lane driving). It is well worth the trip.
Bill, the guitar one
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also loosen the pot (slightly)...turn it back to the origonal start/stop positions while plugged in & see if this gets you back in operation I encounterd the same problem with one of my basses & it worked after that.
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Pete,
I had the same problem with my Europa. In my case, the circuit board was touching the shielding paint - same result, no sound at all. I solved it by taking a small piece of a matchbook, putting it under the circuit board, and tigtening the pots back down. Voila, problem solved, and it worked as good as new. I'd recommend you check to see if the circuit board is touching the shielding paint anywhere. If it is, you might want to try doing what I did.
Hope this helps,
Alan
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Pete,
It sounds like the wood compressed under the pressure of the nut holding the volume pot in place, which is completely normal and why you felt it was a little loose. When it was retightened, the board was rotated enough to allow the solder side of the board to contact the conductive shield and short out as others have advised you.
You can correct this yourself easily. First thing is to visually inspect the boards in the cavity. You should be able to identify if any are in contact with the shield.
Next is to remove the knobs, but do not pull them off. From the owner's manual:
quote:The knobs on your bass are a collet style. You cannot simply pull the knobs off. Doing so will literally rip the shafts right out of the pots.
To remove the knobs, you should:
1. Pry off the cap of the knob with your fingernail.
2. Loosen the collet with a slotted screwdriver.
3. The knob can now be safely lifted from the shaft of the pot.
The skirt on the knob is securely glued to the main section of the knob and will not come off.
Then you can loosen the nut of the offending board, rotate it to a position that is clear of the cavity edge and tighten the nut again. Check to make sure you haven't allowed it to rotate while tightening. You can even hold it in place with your other hand while tightening the nut.
I'll add that it sounds strange you had to put new strings on after a setup and that the bass had no output without the repairman telling you. Maybe they didn't test it?
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Assuming you've figured out the no sound issue from the above advice, it is generally highly recommended by folks around this board that you go here (http://club.alembic.com/index.php?topic=311) for a great primer on doing your own setups.
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Wow! Thanks for all your suggestions. I've been slammed with work the past couple days and haven't had the chance to try what all has been suggested. I know I've got tonight open though and intend on trying to get my bass up and running again.
As for doing my own set-up, I had read the FAQ and checked out links I found from other threads on this board before taking it in. I figured this would be the last time I get it professionally set-up due to how bad the neck seemed to be (I couldn't play an octave anywhere above the 9th fret or so with out it being out of tune!). Kinda learned my lesson the hard way I guess.
I'll also upload the requested photo to see if that sheds any light on this. Thank you all very much. I can't wait to get home from work tonight and try out what you all have suggested. Thanks again,
Pete Reysen
(http://club.alembic.com/Images/394/30534.jpg)
(Message edited by davehouck on August 10, 2006)
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Looks like you've got one of the boards touching the edge:
(http://club.alembic.com/Images/394/30537.jpg)
Rotating the board a touch clockwise will clear it of the shielding. Should have output again after that.
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Yup! You hit the nail on the head! Moved the board a slight bit away from that side wall, plugged it in, and once again I was able to hear my baby sing! Thank you all so much for helping me fix my bass (now if the tech had only set it up the way I liked it! Thanks to all your encouragement, I'll be making all the adjustments myself and get it back to playing the way it should).
As for my future pilgrimage up to Santa Rosa, it's something I've been planning on doing ever since I moved out here (to California) a few years ago. This was a great catalyst and I am determined to make it up there within the next two months.
Thank you all again! Sincerely,
Pete Reysen
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Another happy ending to an Alembic story! Good luck setting her up, Pete. Just remember to take it slow and make VERY small adjustments as you go. Also, when working on the truss rod, action, bridge adjustment, etc., always test it out in actual playing position. Many people make the mistake of doing all these adjustments as the instrument lies prone on the bench. When they pick it up to play they wonder why all of a sudden it's different! It's called gravity - it really can make a difference! As for the Alembic visit, try it, you'll like it.
Bill, tgo
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Me 3! Epic 6 fretted - a mid 90's bass. Just came back from setup by Dan Erlewine. Same issue as above crept in a few weeks later...no sound. Rotating the same board solved it. Thanks!
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Hi Martin, welcome to the board! And congrats on solving the problem!
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Three things are learnt from this thread
1. The shielding paint Alembic use is top quality and not just cheap 'aluminium' based paint(yes they have been used in guitars)
2. Learn to do your own maintenance
3. The Alembic club will always help another Alembic owner whenever possible..maybe we should charge for non Alembic owners or is that not our way?? I guess not..guitar and basses are for life...and not just for Christmas!!
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Makes me wonder if some non-conductive paint should be applied over the conductive layer to avoid/minimize these sorts of problems? I say minimize since one could press hard enough to get through that top layer and hit the conductive layer, but it would be less likely. You need the conductive cage around the electronics to protect it from the outside. It isn't necessary for it to be seen from the inside.
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bsee..I know what you mean..maybe to avoid this happening take the electronics out and line with a good quality electricians insulating tape
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Except of course where the electronics are grounded to the shielding.
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The problem seems to occur with the Epic style of electronics, where most of the pots have a small individual circuit board attached. As the pot is used over time, the nut that tightens the pot to the top wood gets a little loose, and the pot tends to turn a little, which eventually makes the small board short out against the shielding paint on the side of the cavity.
Not sure if it was earlier on this thread or elsewhere, but someone suggested placing a bit of foam between the circuit board and the side of the cavity.
There must be a way to fixate the pot so it doesn't turn any more - something like the screw on the base of a tuning peg. Other than that -use even smaller circuit boards? enlarge the cavity?
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Good point...would have to cut an area for that to ground or screw a fixing tag into the cavity wood and ground at that point.
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The coat of non-conductive paint seems like a bad idea to me.
If the fixing tag is made of conductive material then the pot should still be grounded, would it not? Or perhaps the fixing tag would have to be attached to the body of the pot, rather than the shaft.
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We are getting too complicated now..best just check the boards don't touch the paint..just like Mica says
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Well, if the pot is actually twisting, it will eventually break connections, so doing something to hold the pot still seems a good idea. As a player, you should notice when the throw of the pot changes to favor one side more than the other in terms of range. As far as I have seen, straight up perpendicular to the neck is the middle of the range for all pots as installed.
As far as a non-conductive, it would only have to cover the sides of the cavity. That's the only plain where things can rotate and touch. I don't see any reason why this would be a bad idea.
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Maybe we should add this to the check list of things when there is no sound.
1. Is amp plugged in & switched on(don't forget the stand by)
2. Is venue power tripped
3. Is guitar lead okay
4. Is battery okay
5. Is effects unit working
6. Is volume turned up on guitar and amp
7. Has circuits boards twisted and touching
cavity paint.
I know some of these points are obvious but I bet we have all done them at some time(or know someone who has)