• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Jazz Shielding Pictorial (Big Images Warning)

#861
I've used copper foil to shield all the cavities and rewired using a modified star ground configuration (pup and bridge grounds to a lug, pot grounds to the jack). The bass is definitely quieter and everything works but there's been a general loss of gain and the neck pickup is softer and thinner sounding than the bridge pickup when the two are compared to each other by themselves at full volume. Any idea what I might have done wrong?
Incidentally, I solved the bridge ground problem by putting a small piece of copper tape in the cavity, soldering a wire to the copper tape and running the tape up to make a copper tab under one of the bridge screws.
 
#862
I had great success with this mod. I used Fralin split coil hum cancelling pups on my CIJ 62 Jazz reissue and what was once a quite buzzy and noisy bass is now dead quiet whether my hands are touching the strings or not.
After I had it all installed I noticed that it was recommended to use a 500K blender pot. I assumed since the other pots were 250K that blender pot should be the same so that is what I installed, it seems to work OK and since I am not the swiftest solderer and it's pretty tight in there I would prefer not to do it over.
Am I missing out on anything by having the blender pot at 250K instead of 500K?
 
#864
rabinca said:
I've used copper foil to shield all the cavities and rewired using a modified star ground configuration (pup and bridge grounds to a lug, pot grounds to the jack). The bass is definitely quieter and everything works but there's been a general loss of gain and the neck pickup is softer and thinner sounding than the bridge pickup when the two are compared to each other by themselves at full volume. Any idea what I might have done wrong?
Incidentally, I solved the bridge ground problem by putting a small piece of copper tape in the cavity, soldering a wire to the copper tape and running the tape up to make a copper tab under one of the bridge screws.
Click to expand...

Are the pick-ups out of phase? Try reversing the wires on one of them and see if they are full sounding when both pups are maxed.
 
#865
Im no expert and have only been building kits for 4 months. I use aluminum flashing tape from lowes. I had it from another project and the roll, enough for 100 guitars, is $13. While the tape's glue side is not conductive BUT if you fold it right it all can bevtied together without any soldering. To test, i take a multimeter set to measure resistance and look for connecrionsvon ever piece in the cavity. Joining the cavity is as simple as stripping a piece of extremely thin guage piece of wire and using the same tapevto tpe the ends. The glue on this cheap tape is awesome. I've made silent some problem basses so i know it works. Does anybody see why aluminum is a bad choice? Really shielding is the creation of a Faraday cage. This process is simple, cheap and effective. Since none of my guitars are older than 4 months, i cannot tell you it will last forever.
 
#866
earlysecond said:
Im no expert and have only been building kits for 4 months. I use aluminum flashing tape from lowes. I had it from another project and the roll, enough for 100 guitars, is $13. While the tape's glue side is not conductive BUT if you fold it right it all can bevtied together without any soldering. To test, i take a multimeter set to measure resistance and look for connecrionsvon ever piece in the cavity. Joining the cavity is as simple as stripping a piece of extremely thin guage piece of wire and using the same tapevto tpe the ends. The glue on this cheap tape is awesome. I've made silent some problem basses so i know it works. Does anybody see why aluminum is a bad choice? Really shielding is the creation of a Faraday cage. This process is simple, cheap and effective. Since none of my guitars are older than 4 months, i cannot tell you it will last forever.
Click to expand...

I have used aluminum foil tape and while it does work, and its cheap, it is a pain to solder to. Additionally, shielding the pickup surrounds was a major hassle that involved draping the tape down like a skirt to ensure conductivity. I can tell you that aluminum tape will hold for years without any residue. I use paint for a number of reasons but I also recommend copper tape. I do not recommend aluminum tape because the added benefits of copper, with conductive adhesive, far outweigh the increased cost.
 
#867
earlysecond said:
Does anybody see why aluminum is a bad choice?
Click to expand...
It doesn't conduct as well as copper, you can't solder to it, and as you noted the adhesive isn't conductive. Can aluminum work? Yes, but not nearly as well as copper.

In my opinion, one of the purposes of money is to make one's life better. If I can trade a little bit of money to make something in my life more convenient, I am willing to do it, and this is an example of one of those times. The benefits of saving a certain amount of money by using aluminum tape are far outweighed by the benefit and convenience of using copper. And by the way, the copper tape is not all that expensive, if you shop a bit. You can get a 50 meter roll (165 feet) of 1/2" copper tape for less than $13 on ebay. That won't do 100 guitars, but it will probably do about 40.
 
As an eBay Associate, TalkBass may earn a commission from qualifying purchases.
  • Like
Reactions: selowitch
#868
I prefer the spray paint. As long as you mask off the areas near the cavity where you don't want the paint to end up, it is significantly easier to use and you can do multiple coats if you allow adequate drying time in between. I like the neatness of the results and frankly my fine-motor coordination is not equal to the task of applying copper tape.
 
#869
Thanks Talon,

I agree there is a difference between being frugal and cheap. I am cheap. Thank you for the link.to the copper tape. As soon as i run out of aluminum, I'm going to switch. A quick google search shows that aluminum is only 40% as conductive as copper. Final question, is conductivity a huge issue in Mr. Faraday's equation ? I honestly dont know but if you build a real cage, lead is most commonly used, i believe?
 
#871
Ok so i got over-interested in this subject. Im on a tablet and cant post the link. In a cage application, any metal provides enough free electrons to work well, as long as the skin of the cage has no gaps. In this case, the only advantage copper has is weight. The skin can be thinner to provide the same protection. The article i read, which i cant easily cite says heavy aluminum foil is as good as more expensive materials. It's probably more important to insure there are no gaps in coverage inside the cavity. . . That means I need to tighten up my technique.
 
#872
64lusso said:
Yes especially playing by myself, I've only used it live a few times so far and still working on finding a range of tones I like. What difference do you think I would hear with a 500K blender pot vs the 250K currently installed?
Click to expand...
It will be brighter with a 500K pot. But whether your ears would hear it as "bright" or "harsh" isn't something I can predict. If it was my bass, I wouldn't mess with changing it unless I wasn't getting any clear highs, and I say that as someone who likes a bright tone.
 
#873
earlysecond said:
Ok so i got over-interested in this subject. Im on a tablet and cant post the link. In a cage application, any metal provides enough free electrons to work well, as long as the skin of the cage has no gaps. In this case, the only advantage copper has is weight. The skin can be thinner to provide the same protection. The article i read, which i cant easily cite says heavy aluminum foil is as good as more expensive materials. It's probably more important to insure there are no gaps in coverage inside the cavity. . . That means I need to tighten up my technique.
Click to expand...

No material will perform the job any better than any other, it comes down to what you prefer to work with.
 
#877
Copper is a better conductor than aluminum. Copper tape with electrically conductive adhesive is a better shielding material than aluminum tape with non-conductive adhesive. One is not as good as the other.

Your ears are your anecdotes, and that's fine for you. But unless you tell me you have tested (nearly) identical basses with different types of shielding in all kinds of conditions, your anecdotes are meaningless to me. Sorry, but that's the truth.
 
#879
BlueTalon said:
Copper is a better conductor than aluminum. Copper tape with electrically conductive adhesive is a better shielding material than aluminum tape with non-conductive adhesive. One is not as good as the other.

Your ears are your anecdotes, and that's fine for you. But unless you tell me you have tested (nearly) identical basses with different types of shielding in all kinds of conditions, your anecdotes are meaningless to me. Sorry, but that's the truth.
Click to expand...

I have re-done several aluminum foil and copper foil jobs with conductive paint and each bass was just as silent as running an amp without a bass, regardless of material choice. You are correct that it is anecdotal evidence and it would be impossible for me to provide hard evidence but I suggest trying it yourself, aluminum will silence just as well as copper. Mind you, you will have a more difficult time getting as good of a job but that is mostly due to the lack of conductive adhesive and not the material doing the shielding.

In theory copper is the better material, no argument there, but in terms of practical application for what we're doing the end results are just the same. Heck, there are guys that use kitchen-grade tin foil and get the same results.

@earlysecond why don't you post results if you change the aluminum tape jobs to another material. More anecdotal evidence one way or the other is always appreciated.
 
#880
One of the more interesting things people say about shielding with copper tape with conductive adhesive is that they don't trust the adhesive, that it might "dry out" eventually. I have yet to have anyone tell me that they experienced this themselves, and I ask every time I see or hear someone make that claim. In my experience, as long as the surface is prepped, the adhesive holds just fine and I see no reason why it wouldn't last indefinitely. Now, my experience is my own anecdote, and that has limitations. But the interesting thing about people's doubts about copper tape's adhesive is that some of them therefore decide to use something that's not as good.

If I'm going to the trouble of shielding a bass, it's not something I want to ever have to do again. I want to put in the best shielding I can, and I want it to be permanent. Copper is a better electrical conductor than aluminum, it just is. The conductive adhesive available on copper shielding tape is better than anything available on aluminum tape. I could try using aluminum, and it would probably work in my living room, perhaps even as well as copper. But I have no assurance it will work as well as copper in a bar with lots of fluorescent lights and a computer store next door and a radio station across the street.
 

Latest posts

Top Bottom
Back