| Author | Message | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 232 Registered: 1-2004 |
Hi friends, I used to frequent this forum quite some years ago after I bought a beautiful custom fretless 6. Many things have happened in my life since then, some good, some bad. But as it turns out I recently purchased a 20th Anniversary Alembic, #29 of 200 as part of an estate sale. Some silly person has been mucking with the wiring and I haven't been able to discover how to restore it to the original condition. So, I was wondering whether there was someone here with another 20th who would be willing to make some point-to-point comparisons to help me out? There are some wires that are cut and left dangling, others might have been moved. If anyone is willing to work with me, I'll find a way to get some pics and more details to you. - Karl | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 233 Registered: 1-2004 |
Here's my notes from visual inspection: - Brown wire from 4-way is cut off, goes nowhere - Brown wire from volume is connected to the bottom wire (red/yellow?) on the bridge filter control - On the corner of the jack there's a red/white that goes to the 4-way, there's also another red/white from the same point that is cut (goes nowhere) - Jack also has a black/ground wire that goes nowhere (cut off) - Vol has a black wire soldered to another black wire that goes the the top connection of the bridge filter | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1900 Registered: 5-2006 |
Pictures would be helpful, you can send them to the address in my profile if you can't get them posted. (click my name for profile) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1901 Registered: 5-2006 |
Here's the first pic:  | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 234 Registered: 1-2004 |
Seems I can't edit older posts so here I'm restating the issues with some corrections: - Brown wire from 4-way is cut off, goes nowhere - Purple wire from volume is connected to the bottom wire (pink/white?) on the bridge filter control - On the corner of the jack there's a red/white that goes to the Vol, there's also another red/white from the same point that is cut (goes nowhere) - Jack also has a black/ground wire that goes nowhere (cut off) - Vol has a black wire soldered to another black wire that goes the the top connection of the bridge filter | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 235 Registered: 1-2004 |
So the obvious questions are: - Where should the brown wire from the 4-way go to? - Where should the second red/white from the Jack to to? - The purple that is tied to the pink/white probably each should lead somewhere else, where? - The blacks are probably all grounds, I'll check to see if they are all actually grounded. | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 236 Registered: 1-2004 |
One thing that is likely an issue is the blend control has no ground. There's a cross wire for the blend-output, and the two wires for the inputs, but the other two which should be ground are about 25 ohms from ground. Probably just picking up some ground from the shielding paint. I can connect the free ground wire from the jack to fix that, but the other issues remain. | ||
| stephenr
Advanced Member Username: stephenr Post Number: 215 Registered: 9-2014 |
You may want to try giving Alembic a call on Monday. Pretty sure they will be able to supply a wiring schematic for your model. You can register the instrument with them at the same time. | ||
| gtrguy
Senior Member Username: gtrguy Post Number: 1049 Registered: 9-2004 |
How does the bass function at this time -or- what works and what does not? | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 237 Registered: 1-2004 |
Hi Stephen, I've tried the support route but that schematic is apparently either lost (it was like 25 years ago) or is not publicly available. After having a disfunctional bass for a few months now I thought this was my only remaining option. | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 238 Registered: 1-2004 |
gtrguy, the 4-way switch gives me mute/mute/both/both. With the stereo switch in the other position it's still mute/mute/both/both except that one of the "both" positions sounds a little different. In either "both" position the blend control sweeps between the two pups (though clockwise goes to bridge and ccw goes to neck which seems backwards to me). The Q switches and knobs seem to work fine. I'm guessing a lot of this points to that brown wire from the 4-way. A pinout of the 4-way and the volume control would possibly be enough for me to figure the rest out... I do have lots of experience in electronics so I could get the scope out and look at signals but without knowing where the wires are supposed to be connected I don't think there's much point in that yet. (Message edited by son_of_magni on April 17, 2016) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1902 Registered: 5-2006 |
There shouldn't be a blend (Pan) I'm not sure, but the double pot doesn't look familiar to me... (Mica will know if its original) Controls should be Volume x2 Filter + Q switch x 2, Filter (volume and filter for each pickup), Pickup selector (including silent "standby" position) and the switch is for stereo/mono. | ||
| keith_h
Senior Member Username: keith_h Post Number: 2407 Registered: 2-2005 |
My guess is the wiring changes were to convert the bass to a pan control instead of a volume/volume setup. I'll try to get some pics of my Brown Bass Anniversary electronics tomorrow and post it here. Keith | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 239 Registered: 1-2004 |
Ah ha! Getting somewhere! | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1903 Registered: 5-2006 |
Not 100% sure if this is true for the Anniversary electronics, but I think the volume controls should look like this:  (2 identical boards) So you should have two Filter boards (with the blue trimpot) and two volume controls, once you have that sorted out it shouldn't be too complicated to figure out how everything connects together. :-) Correction to my previous post: -Filter, edited while posting and forgot to erase. (60 minutes threshold for editing post is way to short...) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1904 Registered: 5-2006 |
Pierre-Yves posted this picture of his Anniversary equipped bass, sorry I totally forgot about that pic... :-) You can ignore the unused pot, that's where the Master volume will go after upgrading to Series II electronics.  | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 240 Registered: 1-2004 |
Awesome. So someone replaced one volume pot with a balance control and messed up the function of the 4-way switch and stereo switch. I'll need to get a new volume control and swap it in, the above pic should help a lot. What I can't see is the brown wire from the 4-way but maybe things will work out. | ||
| keith_h
Senior Member Username: keith_h Post Number: 2408 Registered: 2-2005 |
Thanks for the picture Flip. I can't get as good as picture as Pierre-Yves. I tried to get a shot of the volume control with the brown wire but I can't without removing the control and it would still be to close a shot for my camera to get clearly. The brown wire goes to the bridge pickup volume control. In the picture above you see a white/red and red/white wire beneath these are two black wires. The brown wire goes to the hole underneath the left hand white/red and black pair. There should be a yellow wire underneath the right hand red/white and black pair that goes to the filter. I can't tell if your pickup selector is the same as mine or not. It looks a little different but it could just be the angle. Again the wiring is so tight I can't get it out far enough to get a good picture (on the horn in a Brown Bass). I have 10 solder lugs on mine with some of them jumpered. On my bass the brown wire goes to lug 2 that is jumpered to lug 3. For reference there is a black wire to the lug 1 side and a purple wire on the lug 3 side. It is so tight I can't tell you for sure which lugs the other two wires attach to. The purple wire though is for the bridge pickup stereo/mono switch. Your disconnected white/red would go to the left white/red & black pair (or maybe red/white pair. See note) on the bridge pickup volume control board. The other goes to the left hand pair on the neck volume control. Note: My guess is the the red and white striped wires can be either red/white, white/red or a combination depending upon when it was built. Mine are all red/white, yours appears to white/red and Pierre-Yves looks like it has both. So take any talk of red/white or white/red as an either/or/ might be situation. Keith | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 241 Registered: 1-2004 |
My remaining volume control is a 475-020, so my next step is to see if I can get another. Many thanks to Keith and FC. - Karl | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1905 Registered: 5-2006 |
You can order the volume board from Alembic, or send in all electronics and get it back as good as new. :-) I have some spare volume boards, if the Alembic route is to slow I could send you one. (will need Mica to confirm these will go with the Anniversary electronics, they're all the same as the above pic in post 1903) | ||
| son_of_magni
Advanced Member Username: son_of_magni Post Number: 242 Registered: 1-2004 |
I just placed the order, it should be in the mail tomorrow... |
