loose wire in jazz control cavity

[shinobi]

hi guys i was hoping you could take a look at my bass

my input jack was getting a bit problematic so i removed the J control plate. this is what is saw

that loose wire doesn't look good. problem is, i know nuts about wiring, and i don't know if it's always been like that (in a cij? blasphemy!) or if it actually came OFF something

i believe the wire is some kind of ground, and it is routed to the bridge plate

 

[rottenramone]

looks like it did come off. now to fix it back.

 

[shinobi]

nothing beats 24-hour tech support :mrgreen:

solid diagram, though i noticed that on my control plate the black wire for both pups are soldered to the tone pot. i dunno if it makes a diff, but i suppose the last black wire goes there too...

as for the soldering... i guess this is one of those moments where i'm supposed to have some kind of DIY skills

 

[KayCee]

Yes that's the ground wire which is connected to the bridge. Strings are like antennas which will pickup noise, hence the strings need to be grounded. Unless you are using active pickups like EMGs the ground wire has to be there.

Just solder it back to the shell of any pot or on the output jack itself where all the black wires are soldered to.

KC

 

[cherns]

I'm surprised to see that there's no cavity shielding going on in a CIJ! No copper tape/plate, no shielding paint...

Also, you might want to take the opportunity to re-wire your control cavity so that all the grounds come to a common point like in this diagram. This will make your bass ninja-quiet

But you'd need to shield the control cavity for this to work though.

You could also mess with the cap and swap it out with an orange drop or a mallory cap.

 

[shinobi]

i can assure everyone out there that my mind goes blank when i see a schematic like that

oh yah cherns i hope to get the bridge and the jazz rounds soon... ibut i just ordered a pedal and i'm exercising some discipline now

and how will changing the cap help?

 

[cherns]

I'm ready whenever you are!

I offer shielding services as well if you're interested - can do everything at one go... change bridge, strings and shielding... might as well change bass while you're at it

To be theoretical about it, capacitors are like frequency gates. The higher the value of the capacitor, the more it keeps out higher frequencies. In other words, the higher the cap, the "darker" the tone.

Then there's the other less theoretical side to it where people start comparing difference between ceramic, poly and oil/paper...

Some people believe that the type of caps you use can make the difference between good tone, and "magical" tone. But like almost every other piece of gear out there - "The best sounding caps, by far, are the caps the listener believes sound best, followed by the caps the listener wants to sound best."

Edit: Here's a great post I found explaining the use of caps on TB - http://www.talkbass.com/forum/showpost.php?p=5850382&postcount=2

 

[shinobi]

of course... talkbass always has the answer!

i wonder if there's a need to mod the stock electronics though. it probably would be more gratifying to swap it out and pickups as well

maybe i can use parts from my bass to spawn 2 or 3 other basses :twisted:

 

[exin]

Definitely the bridge ground.

The best way is usually to trace the wire and see where it leads too. Most of the time the item/part nearest to the wire would be the one connected to it, in your case, the bridge ground. But sometimes we won't know so gotta be careful.

Anyway, just to share something regarding to grounding

I had my bass preamp swapped out recently from a Seymour Duncan STC-3 (i'm selling it, if you are interested in getting an onboard preamp do let me know) to an AMAZING, and i say again, AMAZING sounding Audere Classic 4 preamp which i got from Cherns The Man.

We got it installed on the bass and on first try it sounded great (i was rushing off that day) and happily brought home the bass, but when i plugged it in and reached for the controls, i heard the most horrible sound that no one wants to hear. ELECTRICAL BUZZ!

So i was wondering what could be the problem, contacted cherns and we troubleshooted, i tore open my bass cavity and tried to rewire a few wires but that didn't work. Brought my bass down to cherns again and we troubleshooted and came to a conclusion that the wiring was connected correctly.

Emailed Audere's tech and he got back to me to wire a wire to my cavity shield and WALA. Problem solved. The instructions said not to wire to the cavity shield but that was needed for my bass.

Regarding shielding, now the preamp's quiet but my pickups are picking up a slight buzz from ... i don't know where but my pickup cavity definitely has no shielding so what i'm going to do is to get some copper foil and shield my cavity the next time i change strings. =). I think that'll bring my bass preamp to near silence if possible.

Just a little something. Hope that helps in some ways.

 

[fgl]

Its a simply ground wire problem. If U blur with the schemetics ...just strip off the end of the wire a bit and solder to any of the 3 pots potface (where U can see the other black ground wires go)

BTW U should have your cavity shielded too - worth the extra effort ...

 

[shinobi]

it's been about a week or so since i sent the bass to CHERNS for wiring and soldering works... and yes, it is worth the extra effort.

needless to say the noise due to the loose ground was solved, but my bass is also noticeably quieter than before the ground wire came off. and as you would expect, the shielding makes it less sensitive to things like fluorescent lights. it gives me some peace of mind

now i'm thinking of those split-single nords so i can forget about 60 cycle hum as well.....

 

[cherns]

Yeah, I was so engrossed with the shielding that I forgot to take pics

I do a complete shielding job which encompasses control + pickup cavities, pickups, pickguard + star grounding.

PM for more info