Is *this* what wiring should look like?!?! Oh my......

[nsmar4211]

Couple years ago I bought a Washburn Fretless bantam for cheap off ebay. I quickly realized I was not a fretless player yet and on the wall it went. I'd pull it down and mess with it every month or so. Started having issues with it cutting out, got to the point where I got no sound at all out of it. Back on the wall it went to wait till I wanted to figure it out.

Fast forward to today-after having learned some soldering skills (basic!) I decided to be brave and check the fretless thinking it was just an input jack needing soldering. When I opened the control cavity, this is what I found (picture is high res. so zoomable):

http://i196.photobucket.com/albums/a..._0125-Copy.jpg

ooooooooooooo. Ok, I'll admit I'm new at this, but I'm pretty sure this shouldn't look that bad....right? After poking the connections a few times, I did start getting a signal again (albeit spotty) so the pickups do work. If it works, it must be hooked up right.....my thought is the intermittancy is due to fraying wires at the connections (espically the lower right pot....wow.....what a mess)

So now I'm thinking of just taking a ton of pictures and notes, desoldering the whole mess and then putting it back together with new wires (same parts)... But I have questions! Anyone have answers?

1.On the upper right pot one of the prongs is bent over and soldered to the pot... is that right?

2.What's with the copper wire running between all the pots? I'm guessing it's some sort of ground....should it be there?

3.Any ideas on improving/simplifying that mess?

4. Any other tips? (besides take it in....not going to spend that much money on a bass I don't really use yet)

More Pictures:
http://i196.photobucket.com/albums/a...1/IMG_0131.jpg

http://i196.photobucket.com/albums/a...1/IMG_0130.jpg

http://i196.photobucket.com/albums/a...1/IMG_0129.jpg

http://i196.photobucket.com/albums/a...1/IMG_0127.jpg

[rumblethump]

What wire did you poke that made it work? If you can isolate it to one wire then just replace that one. Answer to question 1. yes
2. its called star grounding, probably done by the prior owner trying to solve the same problem. I'd check all ground wires first.
I assume this is a vol vol tone tone set up? Interesting that there is two different caps soldered to each tone pot.

[Showdown]

That is an ugly soldering job. One thing you should definitely do is clean the flux (the sticky brown stuff) off the solder joints. It will eat away at them over time if you don't. That is a basic rule of soldering. Whoever did this was very sloppy. Get a small brush and some alcohol and carefully remove it. One like this:

[ddnidd1]

Originally Posted by rumblethump

2. its called star grounding, probably done by the prior owner trying to solve the same problem.

That is the ground wiring, but that is not star grounding.

[rumblethump]

I stand corrected. Please explain the difference? Pics?

[ddnidd1]

Each ground connection is run directly to a single ground point giving you a 'star' shape - sort of

http://mark.rehorst.com/LM3886_amp/a...tar_ground.jpg

[Munjibunga]

There's no difference between the way those pots are grounded and "star" grounding. Once the wire is soldered to all the pots the cases become the same electrical point, exactly the same as with star grounding.

[Stuggi]

Yeah. it's a shoddy mess of an attempt at star grounding, the PO could have used a bit of tutoring on how to wire stuff properly. The solder joints are suspect at best, he must have used a corrosive flux (look at the rust next to the flux residue), he didn't clean it off, and soldering to the back of modern pots should be a calculated risk, not standard practice. Personally I don't solder anything to the back of pots, I shield the cavity and let them ground through that instead. And then again I'm a bit partial to the actual use of grounding the pot cases.

My recommendation to the OP;

Read up a bit on how to wire electric instruments, all you need is a good soldering iron, some good solder and a steady hand along with all the components you want to replace. You could start with cleanly rewiring the cavity, then maybe replace the pots and caps and shield the cavity.


PS: Is that ground conductor between the pots a piece of MIG wire?

[Stuggi]

Originally Posted by Munjibunga

There's no difference between the way those pots are grounded and "star" grounding. Once the wire is soldered to all the pots the cases become the same electrical point, exactly the same as with star grounding.

There's some debate about this among amplifier designers, it's usually called ground plane vs. star ground. Basically it has to do with the small resistance in the ground plane between different ground points on it. I'm not sure yet what to think of it, but I'm pretty sure it doesn't matter much in a passive bass.

[ehque]

Good gosh, that's a complete mess.

1 - Yes. That lug is meant to be grounded.
2 - Those are grounding wires. They are meant to be insulated, to prevent things from shorting out against them. Remove them all and replace with normal wire. If you want you can just wire 3 of the pots to the fourth pot.
3 - I would rip everything out, shield the cavity with copper tape or conductive paint, then re-install with a normal gibson-style schematic. If i was counting pennies i would reuse the pots, but excessive heat from soldering can shorten their lifespans.
4 - What do you want your 4 controls to do?

Gibson-style wiring



@Munji - I don't know, i don't think its a resistance thing. From what i learn in uni-level physics, a loop of conductive wire is basically an antenna, and will pick up noise. A star ground is a specific way of wiring your grounds that has no loops in it. Whether the noise makes it into your signal or not is another matter altogether, but there is certainly a difference between star grounding and normal wiring.

[ehque]

Oh wait, there are better wiring schemes to use. Perhaps a VVT with mute-switch, or a VVT with varitone. Search the forum for options.

[Munjibunga]

Originally Posted by ehque

@Munji - I don't know, i don't think its a resistance thing. From what i learn in uni-level physics, a loop of conductive wire is basically an antenna, and will pick up noise. A star ground is a specific way of wiring your grounds that has no loops in it. Whether the noise makes it into your signal or not is another matter altogether, but there is certainly a difference between star grounding and normal wiring.

Even if the loop did act as antenna, any interference would be shunted to ground.

[rumblethump]

"They are meant to be insulated, to prevent things from shorting out against them."

That may be, but I have seen plenty of passive guitars/basses with bare wire ground connections between pots, from factory, that didn't have any noise problems.

[nsmar4211]

Wow thanks for all the confusion errr help guys

Ok, so this needs to be redone. And I need a wiring diagram to do it. I emailed washburn after looking all over online for one, we'll see if they respond. I did find a diagram resource at guitarelectronics.com but I'll be darned if I even know what type of pickups or features this thing has. Honestly, I want to turn a knob and viola! Sound! I'm simple

It's a four knob setup. When it was working, I figured it has a volume knob for each pickup (although I swear one knob did nothing), a blend knob, and the fourth knob seemed to be a tone knob. Considering I'm used to active basses where it's low/mid/treble volumes, pickup selector, and overall volume....this four knob setup boggles me .

I'm thinking to just desolder the mess and resolder using the pots that are there before spending any money on it. Then, even if I mess up a pot soldering, I've gotten in some practice on soldering the pots.

BTW How on earth would I know what pots to buy if I wanted to change them? I can't read the values on some of them because of the solder....hopefully the washburn people come through with a schematic

I think it's already painted with shielding paint, it looks like my other bass that's painted. Now I'll just have to figure out the ground thing...

[pandathe3]

I'm pretty sure after reading up on the internet for 30-60mins you'll get a basic understanding to passive electronics inside a bass like yours. There really isn't anything to complicated.

I'd personally go buy 4 new pots, 2 orange drop's (If you wanted to keep the original v/t/v/t), a new jack and some wire. It really won't cost you much at. You can practice on the pots that are already inside the bass and just follow the schematic that was posted above some where. Definitely worth the bother.

[Grissle]

Anyone have pics of what really nice soldering should look like??

[PilbaraBass]

I've given up on star grounding...from now on it's purely equi-potential diatomic-bonding isocodecahedral grounding for me...

[Bootzilla]

Originally Posted by PilbaraBass

I've given up on star grounding...from now on it's purely equi-potential diatomic-bonding isocodecahedral grounding for me...

I use space grounding, it relies on interuniversal connections between the componants providing a groundpoint in an alternate universe. Because of the infinite quantity of alternate universes I have an unlimited number of grounds. Plus no wires needed!

It gives some "spacey" sounds if you know what I mean

[nsmar4211]

Whooooooooo! Washburn's customer service came through with a wiring diagram (attached) .


Except I'm a bit lost in figuring it out. It's not much better than the wiring in it..... and heyyy it does look like the factory solders to the top of the pots. Anyone want to try and help me figure this out? Looks like on what I have someone added a capacitor (or whatever you call it... red thing) to the factory mess...

The wires with the slashes through them (darker ones) I'm guessing are ground..... But it looks like there are multiple grounds from wiries going to the top of the F volume pot, a ground plus one leg of a capacitor to the top of the master tone pot, two grounds to the side of the balance volume and THREE grounds to the top of the R volume pot?!.

Maybe the idea of a new wiring harness isn't such a bad one, except I'm not sure what to get. I looked here http://www.guitarelectronics.com/cat...ts.parts_kits/ but neither of the basses has 4 knobs ... so I guess this doesn't qualify as a p bass or a jazz bass style. Then I found the pots page, and I see 250k pots (which is what the diagram calls for, although 3 say b250 and one says a250). Does this mean I could just buy 4 of these puppies : http://www.guitarelectronics.com/pro...ntrol-Pot.html, one of the little "473" thingie (capacitor?), some wire, and attempt to wire them all together? You use the same pot for all four spots? Or is there a difference between a250 and b250?

*sigh* Sorry guys....I'm reading everything I can get my paws on ....

And another question.....what if I used 500k pots? Nevermind, I'll save this question for later

thanks for all the help so far (and the spacey debate hahah)

[warnergt]

Originally Posted by Munjibunga

There's no difference between the way those pots are grounded and "star" grounding. Once the wire is soldered to all the pots the cases become the same electrical point, exactly the same as with star grounding.

I disagree. There is no such thing as the same electrical point unless you
are actually talking about the same physical point. The tiniest bit of
resistance can make a significant difference when the signals involved
are subject to a large amount of amplification. This is demonstrated
by ground loop problems which are very real and have probably been
witnessed by most people here.

The whole reason for star grounding is so that all signals are referenced
from the exact same electrical ground (which turns out to be the exact
same physical point).