Jazz bass has no sound! PLEASE HELP!!

[TastyBass504]

Hello again: one thing quickly, first I love the RS meter!
If the meter is giving you a "1" then touch your probes together first, it should read in the low Ohms, a 1 would mean open. Again I have different meters so it may be just mine: i had one before that indicated "OL" for open.

The contributors to your dilemma are some very bright minds, they're giving you a valuable resource with their experience.

Keep posted!

KB

I touch the probes together and still get a 1…I’m guessing what are you going to say next is that my digital multimeter is bad lol

 

[TastyBass504]

Supposition follows, tread lightly…

Wires broke, why? Maybe the jack got loose and twisted.

Wires now fixed, but multimeter reads a short.

—Is the jack lug now touching the copper tape?

—The jack body will ground against the copper tape anyway. If the hot lead got soldered onto the jack ground lug, that’d short everything as well.

Since I’ve had the bass none of the pots nor the output jack have been loose. From the get-go I made sure that they were secure and tight esp coming from a budget bass factory. I had to shield the bass myself, so I applied copper foil tape. After doing so I never had any issues.
Bass works beautifully, next day no sound btw go easy on my soldering job at the output jack lol it’s not something I’ve practiced much at all!

 

[TastyBass504]

Here's a quick test you can do with a multimeter and an instrument cord. It doesn't require you to disassemble the bass or unsolder any parts. I used a couple of test jumpers to make a solid connection without having to hold the probes down. Your readings won't be exactly the same as mine, but should be in a similar range.

Photo 1: I used a short effect pedal jumper cable in the output jack and some alligator clip "test jumpers" bought at an auto supply. Both volumes and tone at max, DC resistance is 3.5 K Ohms. This is basically the resistance of the two pickups and two volume controls in parallel. The tone control should not affect the DC resistance at any setting.

If the measured resistance is either a short circuit (zero or very low ohms) or open circuit, (infinity ohms) you've got some kind of wiring problem.

View attachment 7297408


Photo 2: 1 volume at "0", the other volume at "10" DC resistance is right at 7 K Ohms, so it's the resistance of one pickup coil in parallel with both volume controls. (Note that this is twice the resistance of "both pickups on")

View attachment 7297410

Photo 3: Both volumes at "0" (zero) DC resistance is 126 K Ohms. This the resistance of the two volume control pots in parallel. With the volumes at zero, the pickup hots are connected to ground essentially taking them out of the circuit.

View attachment 7297422


Since your bass has no sound, I'm guessing it's either a short or open circuit condition.

Btw is that a fretless jazz?

 

[Passinwind]

Your leads are reversed at the output jack.

 

[Matt Liebenau]

Your leads are reversed at the output jack.

Yessir, what Charlie said. The hot and ground are reversed at the output jack. Also, the position the tip contact is in is the most likely to touch the shielding in the control cavity but fix the wiring first.

 

[MirandM]

Tip to avoid these kind of mistakes:

always use black or blue wires for ground
and red wires for signal

in your case you have the signal wire (blue) at the output jack on the sleeve which is also connected to the copper shielding thus making a short

Here's another post with some valuable info on wiring Bass Hoarding Personality Disorder (BHPD) - You are not alone.

 

[MirandM]

something I also noticed, cut the end of the cap wire, it's too long and may at some point touch the copper shielding

 

[TastyBass504]

Your leads are reversed at the output jack.

How’s that? The ground (black) is attached to the sleeve, and the hot (blue) is attached to the tip/live. Is that not correct? I followed this diagram:

 

[TastyBass504]

Tip to avoid these kind of mistakes:

always use black or blue wires for ground
and red wires for signal

in your case you have the signal wire (blue) at the output jack on the sleeve which is also connected to the copper shielding thus making a short

Here's another post with some valuable info on wiring Bass Hoarding Personality Disorder (BHPD) - You are not alone.

So I attached the two wires that came disconnected from the output jack; one blue and one black. I know it’s confusing, but the company is the one who placed these color wires like this. Also, the two wires coming from the neck pickup is blue and black, and from the bridge pickup they are red and black. See where the confusion may be now?
In reference to the comment you made before this one…the output jack had never had an issue before touching the shielding. Any reason why it may possibly touch now?

 

[/\/\3phist0]

How’s that? The ground (black) is attached to the sleeve, and the hot (blue) is attached to the tip/live. Is that not correct? I followed this diagram:
View attachment 7297804

This is yours, Blue is hot +
Red is ground -

See red is attached to back of pot? That is ground , which goes to sleeve, ( which you have attached to blue)

Hence, you are reversed.

 

[MirandM]

View attachment 7297805
This is yours, Blue is hot +
Red is ground -

See red is attached to back of pot? That is ground , which goes to sleeve, ( which you have attached to blue)

Hence, you are reversed.

and shorted because the sleeve of the jack also goes to the mounting screw and hence makes contact with the copper shielding which is also your earth

 

[MirandM]

You want my advice: rewire the whole thing with the right colors otherwise you're even more confused than your wiring.

 

[TastyBass504]

You want my advice: rewire the whole thing with the right colors otherwise you're even more confused than your wiring.

yes I’m really confused! My apologies but this is brand new territory for me. Is the sleeve not in the middle of the jack? This is where the blue (supposed to be ground; it’s how it came from the factory) wire is attached. Also, why would they use blue as the live on the neck pickup, and red for the bridge pickup?
Despite what’s what, I’m gonna take your advice and rewire the whole thing. Any suggestions on where/what wire I should get?

 

[MirandM]

yes I’m really confused! My apologies but this is brand new territory for me. Is the sleeve not in the middle of the jack? This is where the blue (supposed to be ground; it’s how it came from the factory) wire is attached. Also, why would they use blue as the live on the neck pickup, and red for the bridge pickup?
Despite what’s what, I’m gonna take your advice and rewire the whole thing. Any suggestions on where/what wire I should get?

Yes, most of all take lots of time, double check each wire, make sure your soldering is of good quality (train this if you're not sure).

btw, wiring color of pup's in NOT standardized in any way. That is because there are 101 ways to connect pup's in different configurations, usually the two wire that come from the pup have different colors this is to make sure the right phase of the pup is used which varies in those 101 ways to connect them.
So just take a seat and start rewiring all the components, leave the pup's as the last step.

 

[Deleted member 271037]

Yes, most of all take lots of time, double check each wire, make sure your soldering is of good quality (train this if you're not sure).

btw, wiring color of pup's in NOT standardized in any way. That is because there are 101 ways to connect pup's in different configurations, usually the two wire that come from the pup have different colors this is to make sure the right phase of the pup is used which varies in those 101 ways to connect them.
So just take a seat and start rewiring all the components, leave the pup's as the last step.

I agree with what you're saying, but surely there's no need to rewire ALL the components? Shouldn't this just be a matter of:

1) Flipping around the ground/hot wires at the jack.
2) Re-soldering the pickups correctly.
3) Making sure the tip of the jack isn't in a position where it can touch the shielding.

Or am I missing something here?

One more thing: As far as I can tell from the pic, the cavity shielding is only grounded through a mechanical connection between pots > control plate and control plate> cavity shielding. While this usually works fine on standard J-basses (and other basses with a metal control plate) it can also be unreliable if any of the pots or the screws for the control plate ever come slightly loose. This can result in crackling and dropouts. If this was MY bass I would do a soldered ground connection from the cavity shielding to ground (basically just a wire from the cavity shielding to the chassis on any pot). Any theoretical ground loops caused by this shouldn't matter at all with this type of passive guitar wiring.

And like someone else mentioned I would also cut that leg on the tone cap. It probably won't become a problem, but it does seem to be dangerously close to the shielding. Better safe than sorry.

 

[Matt Liebenau]

Don’t worry about the wire colors, as MirandM said above there’s no standardization, it’s not like house wiring where there’s a code. The red wire is attached to the back of the pots, circled in red, that makes it the ground lead. The solder tag that’s obviously connected to the open middle part, circled in black, is what’s called the sleeve and is the ground connection going to the amp thus, in your case, the red wire should be connected there. The long prong on the output jack is called the tip connector and is the hot. The other wire should be connected to the solder lug across from it. If there was a second, shorter prong that would be the ring terminal.

You don’t necessarily have to completely rewire. If the pickups are still hooked up start by switching the output jack connectors and see if the bass works.

 

[MirandM]

I agree with what you're saying, but surely there's no need to rewire ALL the components? Shouldn't this just be a matter of:

1) Flipping around the ground/hot wires at the jack.
2) Re-soldering the pickups correctly.
3) Making sure the tip of the jack isn't in a position where it can touch the shielding.

Or am I missing something here?

One more thing: As far as I can tell from the pic, the cavity shielding is only grounded through a mechanical connection between pots > control plate and control plate> cavity shielding. While this usually works fine on standard J-basses (and other basses with a metal control plate) it can also be unreliable if any of the pots or the screws for the control plate ever come slightly loose. This can result in crackling and dropouts. If this was MY bass I would do a soldered ground connection from the cavity shielding to ground (basically just a wire from the cavity shielding to the chassis on any pot). Any theoretical ground loops caused by this shouldn't matter at all with this type of passive guitar wiring.

And like someone else mentioned I would also cut that leg on the tone cap. It probably won't become a problem, but it does seem to be dangerously close to the shielding. Better safe than sorry.

In this case since this is his first encounter with bass electronics, he'll learn a lot more from doing it from scratch. Yes, someone with experience could solve this in 5 min. but it is important imho that someone with little or no experience but willing to learn should do things the right way from the start.
About the shielding, there are many ways to do that and if you're interested in correct ground wiring (independent of the shielding) you should visit the link I posted a little earlier because it's not like connecting all outsides of the pots and that's it. As an electronics and electrics engineer I've been on the job for 40 years and have seen all kinds of weird thing happening, so I'm pretty well versed in this case.

 

[TastyBass504]

In this case since this is his first encounter with bass electronics, he'll learn a lot more from doing it from scratch. Yes, someone with experience could solve this in 5 min. but it is important imho that someone with little or no experience but willing to learn should do things the right way from the start.
About the shielding, there are many ways to do that and if you're interested in correct ground wiring (independent of the shielding) you should visit the link I posted a little earlier because it's not like connecting all outsides of the pots and that's it. As an electronics and electrics engineer I've been on the job for 40 years and have seen all kinds of weird thing happening, so I'm pretty well versed in this case.

I definitely take your word for what you’re saying, so if I ask any questions, it’s not out of doubt. It’s just more or less curiosity so I can understand.
I had to buy a new multimeter so when I get home this evening, I will be back at it!

 

[TastyBass504]

In this case since this is his first encounter with bass electronics, he'll learn a lot more from doing it from scratch. Yes, someone with experience could solve this in 5 min. but it is important imho that someone with little or no experience but willing to learn should do things the right way from the start.
About the shielding, there are many ways to do that and if you're interested in correct ground wiring (independent of the shielding) you should visit the link I posted a little earlier because it's not like connecting all outsides of the pots and that's it. As an electronics and electrics engineer I've been on the job for 40 years and have seen all kinds of weird thing happening, so I'm pretty well versed in this case.

I went ahead and purchased some heavier guage wires, and only red and black lol
Does this chart look proper to you?

 

[_Obra_]

I purchased a budget jazz bass by Glarry a couple months ago. Up until now, the bass played beautifully after a few minor tweaks. The sound coming from it has always been constant, and all of the pots were without issue…like no crackling or nothing. Last night, I put on my headphones, went to play, and not a sound! Since then I’ve searched the far ends of the internet, YouTube, and even consulted with ChatGPT lol
These are some things mentioned that I’ve already tried:

Check the output jack - I did so, and lo and behold the cheap wiring/soldering had come undone/disconnected. I fixed it with a quick solder job.
Outcome: this did NOT fix the issue!

I was so certain this was the issue. So, I got my ohm meter and checked all the pots, output jack, and they all checked out.
From what I see there’s no disconnected wires. I also checked my instrument cable with the meter while it was jacked into the bass and the cable is good. My amp appears to me fine…with the cable plugged into the amp I touched the other end and I get humming. Tried plugging it into the bass, and I got the famous crackle then nothing. Not a sound. I’m at my wits end, and don’t have the money currently to bring it to a shop…hell I purchased a budget bass so…lol

Anyone ever heard of this!? PLEASE HELP! Thanks.

I'm sorry, I know you don't feel like making jokes, but try taking some sandpaper and sand of the Jazz Bass off the headstock and write ''Precision''- pay attention to spelling! Maybe, but just maybe the problem will go away.

I'm sorry I couldn't resist