Jazz Shielding Pictorial (Big Images Warning)

[Vic]

I recommend also shielding the drilled wire channel -- you can read the last 10-15 pages of this thread for some ideas on that.

this is only necessary if the pickups don't already have shielded wire, and i've found it much easier to simply replace the pickup wire with shielded wire than to try and figure out how to do the wire routes... especially if they're tunnels, where your only other option is copper tubing. too much work. just change the wire out... if need be.

I have the same philosophy for the bridge ground. What I do is make a foundation for the bridge using the copper tape (one layer, no overlap), that covers less area than the bridge, but is big enough to cover the screw holes. I then solder bridge ground wire to that copper where the hole for the ground wire is, and then solder the other end of the wire to the shielded cavity wall.

fwiw, i've never had a problem just taking the stranded bridge wire and fanning it out under the bridge, and making sure the bridge has been sanded on the bottom to remove any (insulating) plating. also, soldering to the shield in the elex cavity does work, but i favor using a ground lug for everything over that.

(1) To truly have a noise-free experience on your bass, you should really have hum canceling pickups. All major pickup manufacturers make them.

true. just note that if it's a j style single coil, the closest sound to a single coil is a split coil, then stacked humbucker (still single sensing), then some may offer side-by-side in the format, but i think that's rare. i always prefer singles if possible, and splits if not.

imho/fwiw

 

[BlueTalon]

I almost said something in my post about some people preferring to use shielded pickup wires instead of shielding the wire channel. I don't do it that way, because it doesn't feel like any extra work to me, and because I don't want to mess with pickup wires.

I do what I do with bridges because I don't want something that works, I want something that can't fail. A grounding lug is something I don't do because it's "too much work." (Funny how our perspectives differ like that.) I just don't see the point unless I'm shielding with shielding paint.

My order of preference for J pickups is split coil, parallel coils, stacks, then singles. Eventually I'm going to try Lace sensors or aluminum pickups to see what they're like.

 

[mickeyj4j]

It is simple, but not necessarily easy. You just have to take your time and be meticulous.

that is what I intend to do.

Start with this copper tape on ebay. It's from an American source (even if you don't care much about that, it will get to you much quicker than shipping it from China), and it's the least expensive you are going to find anywhere.

I understand that i am buying from a local company to me online. not ebay as to much extra shipping.

When you apply it, use something to press each piece to the surface so the adhesive fully engages. Make sure you press everywhere on each piece. I use the back of my fingernail for much of it, and I use a tool for the corners and hard to reach areas. Use multiple layers -- you'll have enough tape to where you don't feel the need to scrimp. Don't leave any gaps -- that would be like putting a screen door on a submarine. The whole point is to keep the bad stuff out.

thanks for these tips.

I'm assuming you have a Jazz bass, since you're posting in this thread. I recommend also shielding the drilled wire channel -- you can read the last 10-15 pages of this thread for some ideas on that. My opinion is that if you are already going to the trouble to do the job anyway, you might as well take a little more time to make sure your shielding job is bulletproof.

actually i did not note the thread. I have an Ibanez SR clone. Neck pickup is P, Bridge pickup is J. What thred would be good to post such enquires in then.

I have the same philosophy for the bridge ground. What I do is make a foundation for the bridge using the copper tape (one layer, no overlap), that covers less area than the bridge, but is big enough to cover the screw holes. I then solder bridge ground wire to that copper where the hole for the ground wire is, and then solder the other end of the wire to the shielded cavity wall.

Nice ideas.

Two other things not related to shielding. (1) To truly have a noise-free experience on your bass, you should really have hum canceling pickups. All major pickup manufacturers make them. (2) Make sure the electrical outlet you plug your amp into is properly grounded. I went to a guy's house one time, plugged in, and got hum & noise. I thought something was wrong with my gear, but it turned out to be an ungrounded outlet. I ran an extension cord to another outlet that was grounded, problem solved.

yes on my old house it has shocking wiring in most plugs which don't help. do you have any ideas. I have a post Extra Hum: - Normal or not detailing my hum problem. wonder if there is anything else I can do.

 

[Vic]

I do what I do with bridges because I don't want something that works, I want something that can't fail.

fwiw, i've never ever had the fanned strands method fail on me if done right. some manufacturers don't, but it's easily fixed.

 

[BlueTalon]

I understand that i am buying from a local company to me online. not ebay as to much extra shipping.

actually i did not note the thread. I have an Ibanez SR clone. Neck pickup is P, Bridge pickup is J. What thred would be good to post such enquires in then.

yes on my old house it has shocking wiring in most plugs which don't help. do you have any ideas. I have a post Extra Hum: - Normal or not detailing my hum problem. wonder if there is anything else I can do.

Glad I could help.

The copper tape on ebay I linked is about $12 for 50 meters of 12mm tape, and the shipping is included in the price (free). If you can get a better deal than that, I am interested in knowing about it.

It is fine to discuss the shielding on your bass here. Your bass has at least one, maybe two holes drilled between the control cavity and the pickups for the pickup wires, and in that way it is similar to a Jazz. A Precision with one pickup has an open cavity all the way, no drilled wire channels. That was the only reason I mentioned a Jazz. So my suggestion to you remains the same about shielding those wire channels.

Regarding the wiring in your old house, I recommend getting a receptacle tester for your electrical outlets. It's something that plugs into your wall outlet and tells you if it's wired correctly or not, including if it's grounded. You can get one online or at any hardware store.

 

[BlueTalon]

fwiw, i've never ever had the fanned strands method fail on me if done right. some manufacturers don't, but it's easily fixed.

Key words there.

 

[Vic]

some manufacturers don't, but it's easily fixed.

Key words there.

of course... it's the entire reason for this thread.

i'm just meaning to say it's not the method that's flawed, only the implementation in some cases... there's no electrical benefit available beyond what a properly done fan strand and sand method provides. fwiw.

i only bring it up because i figure some readers may already be intimidated by the amount of work described here, and adding anything that doesn't carry a clear electrical benefit might not be our best advice for them. that's all. no biggie.

 

[BlueTalon]

of course... it's the entire reason for this thread.

Agreed. It's a discussion. I don't pretend to be the ultimate authority on anything, I just explain what I do and the rationale for it.

If I think something is a good idea (or not), I explain what I think and why I think it. If someone has a different idea than me, and their reason for having it is better than my reason for having mine, I'd be foolish not to reconsider my position.

 

[Vic]

Sorry for reviving an older thread, and many thanks for the marvelous guide! I have a few questions, and I cant seem to find the answers to them anywhere here:

1.) What is grounding the tone pot?
2.) Why ground the bridge itself to the star lug?
3.) Is it necessary to ground the volume and tone pots, if they are bolted to a grounded pickguard with star washers?

*when looking at the back of a pot*

4.) Does it make a difference wiring the volume and tone pots together from the second lug, compared to the third lug?

5.) Does it make a difference soldering the capacitor to the first lug of the tone pot, compared to the second lug?

And finally:

6.) Can I substitute grounding the capacitor and volume pot to the sleeve of the jack by soldering the cap to the first lug of the volume pot, then soldering that lug to the back of the volume pot?

I'll answer generally...

Grounding everything to a common point (star ground) using soldered connections is best and most reliable (and recommended), but it's been my experience that any good mechanical or soldered connection to any well grounded spot is sufficient in a musical instrument. Just, if you're gonna' do it, might as well do it right.

The strings are part of the circuit, as they interact with the magnetic field of the pickups to make the sound. Grounding the bridge is simply a way to keep everything in the circuit on a common ground, and also help reduce noise (RF interference). Same reason it's also generally good practice to ground the bottoms of the pole pieces.

Yes, the lugs make a difference because of how the pots are built inside. Wire them as shown.

 

[tedsalt]

Sorry for reviving an older thread, and many thanks for the marvelous guide! I have a few questions, and I cant seem to find the answers to them anywhere here:

1.) What is grounding the tone pot?
2.) Why ground the bridge itself to the star lug?
3.) Is it necessary to ground the volume and tone pots, if they are bolted to a grounded pickguard with star washers?

*when looking at the back of a pot*

4.) Does it make a difference wiring the volume and tone pots together from the second lug, compared to the third lug?

5.) Does it make a difference soldering the capacitor to the first lug of the tone pot, compared to the second lug?

And finally:

6.) Can I substitute grounding the capacitor and volume pot to the sleeve of the jack by soldering the cap to the first lug of the volume pot, then soldering that lug to the back of the volume pot?

Sounds like you got yourself a project! Got a good soldering iron? No better way to find out than to try it ...

I typically use standard wiring diagrams and shield and ground as needed ...

 

[Vic]

Thanks for the reply!

I thought the bridge already grounds the strings automatically, since its made of nickel? That is why Fender would take a wire under there and use it to ground the pots.. its already a ground.

I also thought that the windings of the pickups ground the pole pieces automatically. Since the windings are wrapped around the pole pieces. The lead wires that are grounded to the star are soldered to the end of the pickup winding, thus also grounding the pole pieces that the pickup windings are wrapped around.

Yeah I'm following the diagram/guide exactly, I'm still curious on how the tone pot is ground, is it from the capacitor being soldered to the jack sleeve, or the fact that its connected to the volume pot which is then soldered to the jack sleeve?

From what I know, when it comes to most 3 lug pots...the third lug is for input, the second for output, and the first for ground (when looking at the back of the pots). It just confused me a bit when the diagram showed the pots connected together from the output lugs, and then put the capacitor connected to the ground lug.

I was taught to connect pots with the third lug and to connect the capacitor to the second lug and to use the first lug as a ground to the sleeve of the jack.

the bridge does ground the strings... but... only if it's grounded.

no, the windings do not make electrical contact with the poles. that wire is insulated. plus you only want the bottoms grounded.

shouldn't be a three lug jack unless it's got a preamp. you don't want a stereo jack for passive basses... it can work, but it's not necessary and confusing.

 

[Vic]

You might have misread what I said, I meant 3 lug pot.. not jack.

After fully shielding the cavities and pick guard (star washers for the pots) ....

Would the diagram below work better or just the same as the diagram on the first page?

The main difference is the capacitor is grounded by connecting it to the 1st lug of the volume pot. That lug is then connected to the 1st lug of the tone pot, which is then grounded to the jack sleeve. And to make sure everything is good, the sleeve is then grounded to the star.

I'm using the input of the tone pot as the hot for the capacitor, and I'm using the output of the tone pot to connect the 2 pots together from the input of the volume pot.

I'm doing this to compensate room to ground both pots. I cant seem to find out how the OP ground the tone pot in the diagram, but this way everything is nice and ground

For the pole pieces..would taping electrical tape underneath the pole pieces be sufficient enough to ground it, in theory it should isolate them from picking up any interference?


View attachment 631426

my bad, yes, if the cap is soldered to the lug that is soldered to ground, clearly that's fine. and chaining all the pot grounds before going to the ground lug is fine. all you really need to do is make sure all grounds are solidly connected together. don't rely on a mechanical connection where corrosion, metal plating, mechanical failure/loosening could compromise ground over time.

 

[Vic]

I have the choice of either soldering the lug (that the capacitor is attached to) to the back of the volume pot... OR soldering the end of the capacitor (that is sticking out of the lug that it's attached to) to the back of the volume pot. Will this even be necessary after attaching the cold end of the capacitor to one of the chained lugs?

again, any spot that is directly connected to ground is fine. no need to sweat this part that much.

As far as grounding the pole pieces, I am going to place electrical tape on the solder joints behind the pickups and then cover the top of the pickup adjustment foam with copper tape and solder a wire from the tape to either the star ground or the shielded pickup cavity.

I don't recommend that... harder to guarantee it might not touch the hot wire/blob on the pickups. Better to just tape a wire across the bottoms and run that to ground. i used conductive foil as tape as well. even the sticky side is conductive.

 

[mickeyj4j]

Yeah, that makes sense. I thought by placing electric tape over the pickup blobs, I can isolate them from touching the copper.

If I understand your correctly, I should tape a wire that runs across all 4 pole pieces of each pickup, then run those 2 wires to the star ground? Should I use electric tape?

i think he said he uses coper tape to do that.

 

[Vic]

i think he said he uses copper tape to do that.

correct. i actually said conductive foil, but copper tape is what i use. they make other types of conductive foil tape, but the copper stuff is nice because the sticky side is carbon impregnated, so it's conductive. that said, when i'm doing sheilding, i don't trust that alone... i still do solder blobs, but fwiw.

 

[Vic]

This is what I'm using:
60mm x 3FEET Copper Foil EMI Sheidling Tape Self Adhisive Guitar Electronics | eBay

I'm not sure if the adhesive side is conductive or not, will that matter when using them to stick a grounded wire across the pole pieces?

No way to know if it's conductive, doesn't say.

This is what I use:

Invalid Link Removed

"The self-adhesive backing is also conductive, so overlapped seams are electrically continuous."

FYI.

As long as the bare wire is held tight to the bottom of the pole, it should be fine. I just like the added assurance of the conductive sticky stuff.

 

[DiabolusInMusic]

This is what I'm using:
60mm x 3FEET Copper Foil EMI Sheidling Tape Self Adhisive Guitar Electronics | eBay

I'm not sure if the adhesive side is conductive or not, will that matter when using them to stick a grounded wire across the pole pieces?

That one does not say. Find an ad that says "double-side conductive" or "conductive adhesive." Do not buy your tape from Stew-Mac, that stuff is highway robbery. You can also source it locally from stained glass supply shops but if you do not have a meter you cannot check for conductive adhesive.

If you are into paint then buy MG Chemicals Supershield. Do not but shielding paint from Stew-Mac, it is low-grade paint they sell for a premium.

 

[Vic]

That one does not say. Find an ad that says "double-side conductive" or "conductive adhesive." Do not buy your tape from Stew-Mac, that stuff is highway robbery. You can also source it locally from stained glass supply shops but if you do not have a meter you cannot check for conductive adhesive.

If you are into paint then buy MG Chemicals Supershield. Do not but shielding paint from Stew-Mac, it is low-grade paint they sell for a premium.

Got some links for the tape? Feel like I have egg on my face right now, but I'm willing to learn and save.

Same for the shielding paint. I did buy some, tho not from stewmac, can't recall exactly what it is right now tho.

 

[DiabolusInMusic]

Got some links for the tape? Feel like I have egg on my face right now, but I'm willing to learn and save.

Same for the shielding paint. I did buy some, tho not from stewmac, can't recall exactly what it is right now tho.

[Invalid or Expired Link Removed]

It is a fraction of the Stew-Mac stuff. There are plenty of sellers on ebay with many different sizes, just search "double sided conductive copper tape." The one issue is that you will occasionally get a lying seller, so having a meter helps to confirm the adhesive is conductive.

The paint is MG Chemicals Supershield, I use the nickel variant but it comes in copper and silver as well. I did not include a pic but I use the aerosol cans of it. I pick it up from my local electronics parts supplier but it can be found online in America. I prefer it to tape these days as it is much easier and faster. I only have experience with Stew-Mac and MG Chemicals paints and the Stew-Mac stuff is junk in comparison.

 

[Vic]

[Invalid or Expired Link Removed]

It is a fraction of the Stew-Mac stuff. There are plenty of sellers on ebay with many different sizes, just search "double sided conductive copper tape." The one issue is that you will occasionally get a lying seller, so having a meter helps to confirm the adhesive is conductive.

The paint is MG Chemicals Supershield, I use the nickel variant but it comes in copper and silver as well. I did not include a pic but I use the aerosol cans of it. I pick it up from my local electronics parts supplier but it can be found online in America. I prefer it to tape these days as it is much easier and faster. I only have experience with Stew-Mac and MG Chemicals paints and the Stew-Mac stuff is junk in comparison.

Got it. Thanks!!