Horizontalste Posted February 6, 2017 Share Posted February 6, 2017 I have been tinkering again (always a bad idea) & have somehow managed to kill the output on my bass. The story so far, swapped the pickup selector switch on my Yamaha Bb for a volume pot, I used a fender schematic & at first managed to get the tone pot acting as a volume, then doing nothing & completely closed & now it's wide open & doing nothing & the output is real low! I'm sure I've got an earth somewhere I shouldn't have but it's doing my nut in. Is it possible I've burnt out the Cap? Suggestions most welcome. Quote Link to comment Share on other sites More sharing options...
T-Bay Posted February 6, 2017 Share Posted February 6, 2017 Is it possible to swap back to the original setup and see if that works ok? Quote Link to comment Share on other sites More sharing options...
Woodinblack Posted February 6, 2017 Share Posted February 6, 2017 Do you have a meter? If so check to see if you have shorted something out. If not, methodically go through your wiring and make sure everything there has a reason to go there. If you think you have a shorted capacitor take it off. Then if all else fails, post a picture, Quote Link to comment Share on other sites More sharing options...
Horizontalste Posted February 6, 2017 Author Share Posted February 6, 2017 [quote name='T-Bay' timestamp='1486400136' post='3231469'] Is it possible to swap back to the original setup and see if that works ok? [/quote] I'm not really sure I can remember how it came apart, the switch was a bit useless to be honest so I didn't pay much attention taking it out knowing I wouldn't be putting it in. I could really do with it for rehearsal tomorrow & jam night on Wednesday :-/ Quote Link to comment Share on other sites More sharing options...
Grangur Posted February 6, 2017 Share Posted February 6, 2017 If it were mine is think I'd disconnect everything and start again. I'm confused by you saying you've replaced a selector switch with a volume pot. Do you mean you've used a 2-pot blend control? I'm guessing it isn't so without seeing it is would hesitate to guess what you've done. Maybe the best way forward here is tell us what pups you have. Also, how many potential positions have you got? From this we can make a suggestion for a circuit layout/diagram and go from there. Quote Link to comment Share on other sites More sharing options...
ikay Posted February 6, 2017 Share Posted February 6, 2017 (edited) A pic is worth a thousand words ... Assuming it's a BB P/J type with a three way switch, the pic below may help you to get it back to its original state. [URL=http://s1090.photobucket.com/user/iankay/media/Stuff/Yamaha%20BB%20wiring.jpg.html][IMG]http://i1090.photobucket.com/albums/i370/iankay/Stuff/Yamaha%20BB%20wiring.jpg[/IMG][/URL] Edited February 6, 2017 by ikay Quote Link to comment Share on other sites More sharing options...
Horizontalste Posted February 6, 2017 Author Share Posted February 6, 2017 I'll get a picture as soon as I get five. It's basically the standard Yamaha Bb425 pickup's minus the three way selector switch, I replaced it because I'd prefer to be able to blend rather than the all or nothing of the switch. So I wired in Vol, Vol, Tone & both Vol pots work as they should but the tone is misbehaving. Each pots live is wired correctly & each is earthed to the next if you know what I mean. The bridge earth & additional earth's from the pickups are all terminated correctly too, for a passive bass there's a lot of wiring. I'll put a picture up when I get home. Cheers fellas. Quote Link to comment Share on other sites More sharing options...
Horizontalste Posted February 6, 2017 Author Share Posted February 6, 2017 [quote name='ikay' timestamp='1486405797' post='3231540'] A pic is worth a thousand words ... Assuming it's a BB P/J type with a three way switch, the pic below may help you to get it back to its original state. [URL=http://s1090.photobucket.com/user/iankay/media/Stuff/Yamaha%20BB%20wiring.jpg.html][IMG]http://i1090.photobucket.com/albums/i370/iankay/Stuff/Yamaha%20BB%20wiring.jpg[/IMG][/URL] [/quote] Exactly that but now minus the switch :-) Quote Link to comment Share on other sites More sharing options...
ikay Posted February 6, 2017 Share Posted February 6, 2017 Put the switch back! Quote Link to comment Share on other sites More sharing options...
Woodinblack Posted February 6, 2017 Share Posted February 6, 2017 [quote name='Horizontalste' timestamp='1486408390' post='3231576'] Exactly that but now minus the switch :-) [/quote] Well, not exactly that as you say you have 2 volume controls. So can you elaborate on 'misbehaving' - not really a good description to work out what is happening. Quote Link to comment Share on other sites More sharing options...
Horizontalste Posted February 7, 2017 Author Share Posted February 7, 2017 Thanks for your input so far fellas. Tonight I have stripped the loom down completely & built it back up using quite a bit less wire than Yamaha did & the Jazz wiring diagram. When I'd put it back together & plugged in the neck pickup & tone control worked perfectly but no bridge pickup. On inspection I noticed I'd managed to knock the hot wire from the bridge pickup off the pot so I soldered it back on & quest what? No tone control & half it's normal output! I've taken it off again so I can use it tomorrow & Wednesday with just the neck pickup but I'm guessing now the pot I used for the bridge is knackered. I shall find another & try again. Quote Link to comment Share on other sites More sharing options...
Woodinblack Posted February 7, 2017 Share Posted February 7, 2017 Very unlikely that you have broken the pot - they are pretty robust. Even if you had, even with a broken pot there isn't a scenario I could think of that would halve your volume by connecting the pickup to it. Quote Link to comment Share on other sites More sharing options...
Ghost_Bass Posted February 8, 2017 Share Posted February 8, 2017 Thet's clearly a case of bad wiring. I'm sure there's something either connected to wrong place or with a dry joint. Tricky part is that the more we look at the wiring less obvious seems to be the problem, trust me, it happened to me more times than i want to remember. Solution: Unsolder everything, i mean everything - every single wire and cap from the pots - then start again fresh following the Fender diagram. Solder all the grounds (leave the pickups to the end) together between the pots and jack. Solder the wires for the hot signal between pots and jack. Then solder the cap back in. Finally solder the pickup wires in. Tip: Since you're converting your bass in a VVT move the tone to the hole where you had the switch. Replacing the switch with a volume pot will leave you wuth a VTV config and would make it much harder to do a visual comparison with the Fender diagram drawing. If all fails just order a brand new wiring loom from kiogon. And if you need to use it live in a hurry just solder both pickups straight in to the jack and sort the tone with the amp's EQ just to get you by. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.