clashcityrocker Posted January 14, 2014 Share Posted January 14, 2014 (edited) Hi all Have brought myself some Ultra jazz pups and an upgraded wiring loom/pots. Have fitted it all per instructions,but have a problem; The two volumes only work on full turn,as soon as they are turned down at all,the sounds disappears. Obviously not good. The instructions are ; Red to pos Green to neg Then a black and a white wire soldered together n left alone Bridge ground to neck negative Any help would be great,it's a cv jazz if that helps,and cts pots Thanks Edited January 26, 2014 by clashcityrocker Quote Link to comment Share on other sites More sharing options...
paul_5 Posted January 14, 2014 Share Posted January 14, 2014 Have you checked the taper of the pots? Sounds like a Linear pot when it should be a Logarithmic one. When you say you turn the volume pot down a fraction the sound disappears does *all* of the sound disappear, or just the output from that particular pickup? Quote Link to comment Share on other sites More sharing options...
Grangur Posted January 14, 2014 Share Posted January 14, 2014 The resistance on a pot can be logarithmic, rather than linear. On the pots you have 3 terminals. Try changing the connections by swapping the 2 end ones over. It may mean that the knob may work the opposite way to that which logic would tell you, but it might sort the problem. Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 14, 2014 Author Share Posted January 14, 2014 [quote name='paul_5' timestamp='1389699186' post='2336948'] Have you checked the taper of the pots? Sounds like a Linear pot when it should be a Logarithmic one. When you say you turn the volume pot down a fraction the sound disappears does *all* of the sound disappear, or just the output from that particular pickup? [/quote] Just that pick up Thanks for the replies, would there be different pots to suit these pick ups? Quote Link to comment Share on other sites More sharing options...
BOD2 Posted January 14, 2014 Share Posted January 14, 2014 Check the full wiring against this (but note that the wire colour codes are different in that diagram,, notably Seymour Ducans RED = DiMarzio BLACK and Seymour Duncan BLACK = Dimarzio RED) [url="http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=jazz_bass_stacks"]http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=jazz_bass_stacks[/url] Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 14, 2014 Author Share Posted January 14, 2014 [quote name='BOD2' timestamp='1389708626' post='2337074'] Check the full wiring against this (but note that the wire colour codes are different in that diagram,, notably Seymour Ducans RED = DiMarzio BLACK and Seymour Duncan BLACK = Dimarzio RED) [url="http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=jazz_bass_stacks"]http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=jazz_bass_stacks[/url] [/quote] I think that's how iv wired mine,except they are solderedless pots so have a negative or earth side and the positive or red side Arrr this is doing my head in! Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 26, 2014 Author Share Posted January 26, 2014 I'm still no wiser as to the problem here. My local music shop thinks they are thr wrong type of pots but I'm not convinced. They are marked 250k CTS pots. The tone rolls on and off smoothly but thr pick ups are still nothing nothing nothing boom,full volume. Any suggestions? Thanks Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 26, 2014 Author Share Posted January 26, 2014 [quote name='Grangur' timestamp='1389699215' post='2336949'] The resistance on a pot can be logarithmic, rather than linear. On the pots you have 3 terminals. Try changing the connections by swapping the 2 end ones over. It may mean that the knob may work the opposite way to that which logic would tell you, but it might sort the problem. [/quote] I tried this and nothing changed at all,not even how the knobs worked Quote Link to comment Share on other sites More sharing options...
BigRedX Posted January 26, 2014 Share Posted January 26, 2014 Sounds like you have linear rather than log pots. What's the letter suffix on the pot after the value - A or B? Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 26, 2014 Author Share Posted January 26, 2014 [quote name='BigRedX' timestamp='1390756106' post='2349075'] Sounds like you have linear rather than log pots. What's the letter suffix on the pot after the value - A or B? [/quote] All 3 pots have this stamped on them.. 450S2774 250k 1320 CTS So neither A or B Thanks for your help Simon Quote Link to comment Share on other sites More sharing options...
Delberthot Posted January 26, 2014 Share Posted January 26, 2014 I had exactly the same problem as you when I was trying to have two volumes and two tones. As soon as I turned one pickup slightly down it cut out completely. Tried everything and could not get it to work - different wiring, different pickups to make sure that it wasn't them at fault but nothing worked. The solution? Abandoned the whole lot and fitted a set of EMGs Not the answer you need but myself and a couple of forum members spent a hell of a lot of time trying to solve it but couldn't fathom it out Quote Link to comment Share on other sites More sharing options...
BigRedX Posted January 26, 2014 Share Posted January 26, 2014 Can you take a large clear photograph of the wiring or draw a diagram and post it? That might help work out what is going wrong. Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 27, 2014 Author Share Posted January 27, 2014 [IMG]http://i1092.photobucket.com/albums/i416/me_and_the_bastards/DSC_0096.jpg[/IMG] So each pick up has a red n green wire,but also a black one and a white one,these two are soldered together and left,as per instructions Thanks alot Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 27, 2014 Author Share Posted January 27, 2014 [IMG]http://i1092.photobucket.com/albums/i416/me_and_the_bastards/DSC_0096.jpg[/IMG] So each pick up has a red n green wire,but also a black one and a white one,these two are soldered together and left,as per instructions Thanks alot Quote Link to comment Share on other sites More sharing options...
BigRedX Posted January 27, 2014 Share Posted January 27, 2014 I can't see anything attached to the third leg of the volume controls. They should be wired to earth. Quote Link to comment Share on other sites More sharing options...
Grangur Posted January 27, 2014 Share Posted January 27, 2014 There is a white wire that appears to link all the 3rd terminals. If this is connected to earth, then that might be ok, except this should also earth the case of each pot. You've then connected the variable resistor across the 2 wires of the pots. What you should have here is the red wire going to the centre leg of the pot and the green one going to earth - the same leg as the white lead, and to the casing. It would all be easier if you learn to solder, rather than try to use terminal blocks. Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 27, 2014 Author Share Posted January 27, 2014 This is how the pots were supplied, and it seems like everything is wired up as it should be so I'm baffled. I might re fit the original pick ups to these new pots ,see if that sheds any light on which part is not doing what it should Quote Link to comment Share on other sites More sharing options...
BigRedX Posted January 27, 2014 Share Posted January 27, 2014 Why are the red and green wires swapped round on the second volume pot? I can see a black wire connected to the same terminal as the red one on the first volume pot - where does it go? Quote Link to comment Share on other sites More sharing options...
BigRedX Posted January 27, 2014 Share Posted January 27, 2014 Also do DiMarzio actually describe what the four wires from each pickup do? That would help with tracking down where this has gone wrong. Looking at the photo you posted my suspicion is that you have a wire missing from the second volume pot that should be going to wherever the black wire from the first volume pot goes. The multiple earth wires are IMO not a good idea as they make the circuit unnecessarily complicated and could lead to earth loops in extreme circumstances. Did you buy the control plate as a single pre-wired unit? It all looks a bit of a mess really. Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 27, 2014 Author Share Posted January 27, 2014 [quote name='BigRedX' timestamp='1390809126' post='2349629'] Why are the red and green wires swapped round on the second volume pot? I can see a black wire connected to the same terminal as the red one on the first volume pot - where does it go? [/quote] That was me just trying different things. The extra black wire is the bridge ground from the bridge. Yes pre attached to bell plate, These are the instructions with the pups. [IMG]http://i1092.photobucket.com/albums/i416/me_and_the_bastards/DSC_0029.jpg[/IMG] Quote Link to comment Share on other sites More sharing options...
BigRedX Posted January 27, 2014 Share Posted January 27, 2014 (edited) So that extra black wire is soldered to the casing of the pot and not connected to the red wire? So how are the volume pots connected to the output? AFAICS the wiring from the pickups is fine. The wiring on the control plate is the problem. Edited January 27, 2014 by BigRedX Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 27, 2014 Author Share Posted January 27, 2014 The black bridge ground wire is put into the pot negative with the green pick up wire.I think il have to take it to a music shop and get them to have a look. Is the linear /long pot theory not applicable any more? Thanks so much for your help BRX Quote Link to comment Share on other sites More sharing options...
Grangur Posted January 27, 2014 Share Posted January 27, 2014 (edited) Here's the link to the wiring diagrams on the DiMarzio web site. [url="http://www.dimarzio.com/support/wiring-diagrams#1-6-2"]http://www.dimarzio....-diagrams#1-6-2[/url] Reading the 2 top circuits: 2 Humbucker Bass Set (Parallel), 2 Volumes, 1 Tone 2 Humbucker Bass Set (Pickups Wired in Parallel), 2 Volumes, Master Tone They say the black and green should be soldered together and connected to ground/earth. - You have green to the pot. They say the red and white should be connected to the centre terminal on the volume pots. May I suggest you start again with the wiring diagrams? Good luck Edited January 27, 2014 by Grangur Quote Link to comment Share on other sites More sharing options...
clashcityrocker Posted January 27, 2014 Author Share Posted January 27, 2014 [quote name='Grangur' timestamp='1390849103' post='2350366'] Here's the link to the wiring diagrams on the DiMarzio web site. [url="http://www.dimarzio.com/support/wiring-diagrams#1-6- 2"]http://www.dimarzio....-diagrams#1-6-2[/url] Reading the 2 top circuits: 2 Humbucker Bass Set (Parallel), 2 Volumes, 1 Tone 2 Humbucker Bass Set (Pickups Wired in Parallel), 2 Volumes, Master Tone They say the black and green should be soldered together and connected to ground/earth. - You have green to the pot. They say the red and white should be connected to the centre terminal on the volume p May I suggest you start again with the wiring diagrams? Good luck [/quote] I will give this a try. Iv seen about 6 differing instructions from dimarzio, not very helpful of them!cheers Quote Link to comment Share on other sites More sharing options...
BigRedX Posted January 27, 2014 Share Posted January 27, 2014 Just reading the scan of the pickup wiring instructions from DiMarzio that you posted. You have the green wire from the pickups going to totally the wrong place. It should be soldered to the back of the volume potentiometer. The Red wire goes to the centre tag of the volume pot. Quote Link to comment Share on other sites More sharing options...
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