Jump to content

Questions about a bass project...


Preacher

Recommended Posts

  • Members

Howdy folks, I usually hang out over at HCEG but came upon a project for a friend that is beyond my expertise.

 

The bass in question belongs to an older friend of mine who I jam with occasionally. He had a funk/ soul band in the 70's and is just an all around cool cat, nevermind a fantastic bass player. I've worked on a guitar of his (headstock break and electronic tuneup) but he recently asked me to work on his bass. It seems the output is really shaky. I also noted it looked like someone did a mega sketchy refinish job way back. I asked him if he wanted me to redo it and he immediately said yes.

 

This P-bass appears to be a mid-70's part-caster. The neck plate seems 1970, the body 1972, and the neck (which I find to be pretty sweet) a 1974 fretless maple. First some pictures...

 

HPIM1570.jpg

HPIM1580.jpg

HPIM1575.jpg

HPIM1573.jpg

HPIM1584.jpg

Link to comment
Share on other sites

  • Members

As for the electronics (and my main concern)...

 

I opened it up and quickly found the source of the inconsistent signal - the wire to the jack is barely connected and tenuously held in place be a screw through the lug (also - no ground path to the jack :freak:).

 

I also found a number of other interesting things inside. It looks to me like one dpdt switch is being used for phase reversal (?) on the p-bass pickup - also one for pickup selection - then a little guy as a kill-switch...

 

HPIM1597.jpg

HPIM1599.jpg

 

Here is quick and dirty schematic of what I *think* is going on (EDITED)...

Jessies_Bass_Wiring_V2.gif

Link to comment
Share on other sites

  • Members

Sooo...As I said, I'm no bass player and I have no idea what effects and wiring schemes make sense.

 

Which pots should be used - 250K alright or would 500K be better? How can I make the most of the humbucker in the neck? Should the inputs be on the center lug or should I move them off?

 

Any advice or input would be awesome...

Link to comment
Share on other sites

  • Members

I believe for a bass used for funk the 500K pot would be better.


Yeah, that body needs some sanding, but I wouldn't touch that neck!

 

Dumb question - 500k on the tone pot or all of them?

 

Oh and the neck :evil:- I've stripped the poly off the back of the neck and headstock - but left the headstock face intact as well as the poly over the neck stamps and sides of pocket; I wanted to retain the fit it had. I've since put 3 coats of tru-oil on the stripped areas (after a very light medium brown transtint coat followed by a bit of honey amber) and it's feeling great.

 

I lightly cleaned the fretboard but that is it. I've toyed with maybe throwing a very light coat of tru-oil on the fretboard just to give it a little protection...still up in the air...

Link to comment
Share on other sites

  • Members

 

Recheck the wiring on P1 - I'm pretty sure you got that wrong as it appears to be the tone pot. The back-asswards wiring on P2 and P3 is the standard way of wiring a two pickup "VVT" (volume volume tone) setup - jazz basses are wired that way.

 

 

You sir, are correct about my mistaken diagram; yes, I seem to recall the input on center lug and signal out to jack and kill switch on the left lug (see below). I don't have it in front of me but I'll recheck it when I do. Thanks for the info re: J Basses as well. Interesting...

Link to comment
Share on other sites

  • Members

Dumb question - 500k on the tone pot or all of them?


Oh and the neck
:evil:
- I've stripped the poly off the back of the neck and headstock - but left the headstock face intact as well as the poly over the neck stamps and sides of pocket; I wanted to retain the fit it had. I've since put 3 coats of tru-oil on the stripped areas (after a very light medium brown transtint coat followed by a bit of honey amber) and it's feeling great.


I lightly cleaned the fretboard but that is it. I've toyed with maybe throwing a very light coat of tru-oil on the fretboard just to give it a little protection...still up in the air...

 

 

500K on the tone pot.

 

I always oil my fretboards. I use 3-in-1 oil and a cotton swab. They stay oiled a long time with that.....years in fact.

Link to comment
Share on other sites

  • Members

 

Recheck the wiring on P1 - I'm pretty sure you got that wrong as it appears to be the tone pot. The back-asswards wiring on P2 and P3 is the standard way of wiring a two pickup "VVT" (volume volume tone) setup - jazz basses are wired that way.

 

 

Ok, checked again, and no, kill switch also feeds off center lug - I've updated the gif above...

Link to comment
Share on other sites

  • Members

How does your friend want the body refinished? Stripped and tung-oil? Painted? Stained a new color? Does he want some creativity from you, or just getting it in good shape looking the way it was?

 

Good question. I asked him and he told me to do whatever I thought appropriate. I decided to do a satin/worn tru-oil finish with a subtle burst as a nod to it's sunburst past. I respect the age of this instrument and wanted to leave some of the dings and imperfections in it - I want it to be recognizable and feel and play like an old friend. We'll see how it turns out. So far...

 

Back of the neck...Tru-oil_neck_3coats.jpg

 

Body after 3 coats of tru-oil...

Tru-oil_body_front_3Coats.jpg

Tru-oil_body_back_3Coats.jpg

Link to comment
Share on other sites

  • Members

 

Close - but normally the center of the tone pot is tied to the lug that goes to the output jack.

 

 

I think I'm misunderstanding you (not your fault - I'm just a little slow sometimes. Ok, maybe not just a little). As it stands right now there is nothing on the left lug of the tone pot but the output to jack. I understand this also to be a feature of "standard" Jazz bass wiring. Should there be something else?

 

Also - grounding and shielding is a pretty big deal in electric guitars - should I be concerned with that on this bass?

Link to comment
Share on other sites

  • Members

I think I'm misunderstanding you (not your fault - I'm just a little slow sometimes. Ok, maybe not just a little). As it stands right now there is nothing on the left lug of the tone pot but the output to jack. I understand this also to be a feature of "standard" Jazz bass wiring. Should there be something else?

Nope, not normal:

jb.jpg

Link to comment
Share on other sites

  • Members

 

I believe for a bass used for funk the 500K pot would be better.


 

 

Maybe for slap funk. But this is a fretless and they guy was in an old school funk band? not sure the extra zing from the 500ks would be a good thing

For fretless I would go 250k pots.

Link to comment
Share on other sites

  • Members

Pickup_coils_soldered.jpg

 

Ok, took the pickup apart - one coil was fine, the other, not so much. Unwound about 1/3 of it before concluding a complete rewind would be necessary to fix it (the winding was soldered to the lead inside the bobbin :mad: ).

 

So, I asked my buddy what sound he was looking for; when he replied "something kinda spanky - you know funky," I told him I didn't think the neck postion would quite be able to get us there. But still - what would get us closer to that - lipsticks? Rails? A split humbucker? Any input would be appreciated. :thu:

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...