• 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.

properly shielding a bass

TinyE

TinyE

Jan 31, 2013
1,063
905
portland,or
#1
I play a Fender MIM Jazz.
I never really had any issues with it, and it has always sounded pretty good, but I always ran both vol pots all the way open because if I turned one of them down at all, I got a slight noise.

Then we played a gig in SF, and the building had powerlines above it. My bass buzzed so loud, even with both vols all the way up, i had to turn my tone pot all the way down, which killed my tone.

I did a little research online, and found that I probably just needed to shield it a bit, so I bought 6' of 2" copper tape off ebay (about $5), and pulled everything out.

Arguably, i got a little carried away. I used all 6' of tape. I taped in the pickup chambers, the pot chambers, and covered the back of the pickguard completely in copper.

I played it for the first time last night through my amp, and all I can say is wow. If I had only known.

I can now adjust vol on either pot independently, no buzz at all. I now have access to a million tones through my rig that I had only searched for before. Punchy, Jazzy, even got a Ric tone last night using a pick. I did all this to prevent external noise from infiltrating my signal, but it has done so much more.

I am just posting this in hopes that I might help at least one more of you that hadn't figured this out yet.

The MIM bass is really unbelievable sounding now. You no longer need ROLAIDS for G.A.S. removal! Just buy some copper shielding!
 
  • Like
Reactions: carsbybigd and DiabolusInMusic
#4
Thanks for the experiment and the report. Because standard Jazz pickups are single-coil, a lot of people figure that occasionally horrible EMI noise is unavoidable without swapping pickups. Thanks for demonstrating that that's not necessarily the case. And maybe that Fender is cutting costs and corners a bit more than they should for a $600 instrument.
 
#5
Yes. I would say an easy corner was cut. It can't cost that much to spray inside with shielding paint at time of manufacture. In any case, it may be a placebo effect, but I think the bass sounds way better, and more powerful if that is possible.

I was convinced that I needed new expensive pickups (almost bought the split fralins).
 
  • Like
Reactions: carsbybigd
#6
Sid Fang said:
Thanks for the experiment and the report. Because standard Jazz pickups are single-coil, a lot of people figure that occasionally horrible EMI noise is unavoidable without swapping pickups. Thanks for demonstrating that that's not necessarily the case. And maybe that Fender is cutting costs and corners a bit more than they should for a $600 instrument.
Click to expand...

Single coil pickups are prone to interference that cannot be removed without adding a dummy coil. It is just easier to change the pickups to humbuckers. Single coils get 60hz hum when they are not in balance. Shielding will do nothing to remedy this as shielding only affects RF interference.

Fender doesn't do shielding on their CS instruments either, at least not the ones I have seen (which admittedly isn't much.)
 
#7
hmm.... thanks for the info. I just bought a Peavey Zodiac DE with the chrome pickguard- pickups on this are Seymour Duncan Quarterpound P and J. The J pickup has humming when I'm too close to a device so I'm guessing shielding the bass would work wonders as it has little shielding near the pots. Pickguard is chrome, and noticed there's no tape underneath.
 
Last edited:
#9
I installed an Alembic pup in my precision.....man talk about noise [well part of it was the wrong jack had been installed] Alembic asked if I had it shielded ....nope . Got some copper tape off of the bay did it up and got the right jack and ..Walla !! Great sound and No HUM !
 

Attachments

  • 006.JPG
    006.JPG
    679.6 KB · Views: 117
  • 008.JPG
    008.JPG
    26.1 KB · Views: 119
#11
Sid Fang said:
Thanks for the experiment and the report. Because standard Jazz pickups are single-coil, a lot of people figure that occasionally horrible EMI noise is unavoidable without swapping pickups. Thanks for demonstrating that that's not necessarily the case. And maybe that Fender is cutting costs and corners a bit more than they should for a $600 instrument.
Click to expand...

Well, in my experience Fender's are variable. My MIM Deluxe jazz V came with conductive paint and really it wasn't THAT bad. But there was always this little bit of hum that of course got worse when you were in a noisy venue. So I bit the bullet and got out the copper foil and shielded it ALL... even the wood behind the football side jack.

I can't say it made a huge difference in hum because the original hum wasn't all that bad. but the TOTAL lack of hum made a HUGE difference in my love of that bass! That shield job plus my new SCN pickups and that bass just came alive in my hands! :bassist:
 
#13
(Debbie Downer here.) Umm, when shielding with copper or aluminum tape, all over laps must make contact. Usually, the adhesive backing prevents contact when over lapped and solder has to bridge the pieces together.

A good thing to do is to use a voltmeter to check and make sure that all pieces of shielding tape are making contact with the other pieces. If not, then there is only partial shielding.

Shielded cable is also a good idea to use from the pickups to the pots and from the pots to the output jack.

Shielding paint is really, really nice to use and also very expensive to buy a container of the stuff.

Shielding the inside of the pickup covers is a waste of time unless if the shielding tape or paint makes contact with the rest of the shielding job.

Finally, when both Jazz Bass pickups are run together on full, it works as a humbucker. When one or the other pickup is turned down or off, it reflects single coil hum.

Always make sure that the bridge has a good contact ground wire running to the grounding in the control cavity (check with voltmeter). (When our hands are off the strings, there can be a slight audible grounding issue.)

Or buy humbuckers and forget about shielding.
 
#14
DiabolusInMusic said:
Single coil pickups are prone to interference that cannot be removed without adding a dummy coil. It is just easier to change the pickups to humbuckers. Single coils get 60hz hum when they are not in balance. Shielding will do nothing to remedy this as shielding only affects RF interference.

Fender doesn't do shielding on their CS instruments either, at least not the ones I have seen (which admittedly isn't much.)
Click to expand...

Not meaning to trash your opinion, but I have a very different point of view.

IME, a good shield job will cut most of the interference from outside sources. Even humbuckers can pick up interference, and shielding is just as important on a humbucker equipped bass as single coil, IMO. Hum will always be present when single coils are not in balance, but the noise is much worse when a bass is not shielded and interference noise is added to the hum.

The fact that Fender doesn't shield instruments shows they are stuck in the '50s and can get away with whatever they want because they are Fender. ;)

It may be "easier to change to humbuckers," but easier doesn't mean it sounds the way you want it to when you are done. For me, anyway, nothing can compare to the tone from a single coil Jazz pickup.

All that said, I understand where you are coming from if you can get the tone you desire from humbuckers.
 
#15
DiabolusInMusic said:
Single coil pickups are prone to interference that cannot be removed without adding a dummy coil. It is just easier to change the pickups to humbuckers. Single coils get 60hz hum when they are not in balance. Shielding will do nothing to remedy this as shielding only affects RF interference.

Fender doesn't do shielding on their CS instruments either, at least not the ones I have seen (which admittedly isn't much.)
Click to expand...

I have to say, my shielding has removed all noise. I can independently change either volume know without introducing noise. That didn't use to be the case. I was convinced I needed humbuckers. Perhaps I just got lucky? In any case, my bass is dead silent at any setting combination. It's a thing of beauty.
 
#17
bassdude51 said:
(Debbie Downer here.) Umm, when shielding with copper or aluminum tape, all over laps must make contact. Usually, the adhesive backing prevents contact when over lapped and solder has to bridge the pieces together.

A good thing to do is to use a voltmeter to check and make sure that all pieces of shielding tape are making contact with the other pieces. If not, then there is only partial shielding.
Click to expand...

Most copper tape for guitars has conductive adhesive. Just do a continuity check on all the pieces to make sure you have good continuity. (Meaning your ohm meter should read as close to 0 as possible from any two points on your shielding job. )
 
#18
WoodyG3 said:
Not meaning to trash your opinion, but I have a very different point of view.

IME, a good shield job will cut most of the interference from outside sources. Even humbuckers can pick up interference, and shielding is just as important on a humbucker equipped bass as single coil, IMO. Hum will always be present when single coils are not in balance, but the noise is much worse when a bass is not shielded and interference noise is added to the hum.

The fact that Fender doesn't shield instruments shows they are stuck in the '50s and can get away with whatever they want because they are Fender. ;)

It may be "easier to change to humbuckers," but easier doesn't mean it sounds the way you want it to when you are done. For me, anyway, nothing can compare to the tone from a single coil Jazz pickup.

All that said, I understand where you are coming from if you can get the tone you desire from humbuckers.
Click to expand...

Humbuckers only buck 60hz hum, they do nothing for RF interference. I wasn't talking about chaing to them to remove all hum. Shielding is most definitely still required for humbuckers, that is a fact not your opinion. ;) I also agree about the tone from single coils. As much as I hate 60hz hum, I love that tone. I mean it is easier to change to humbuckers than it is to add a dummy coil, the soloution for 60hz noise. This is how they make humbuckers, so it will also affect tone.

Oh and +a million about Fender.

TinyE said:
I have to say, my shielding has removed all noise. I can independently change either volume know without introducing noise. That didn't use to be the case. I was convinced I needed humbuckers. Perhaps I just got lucky? In any case, my bass is dead silent at any setting combination. It's a thing of beauty.
Click to expand...

You just haven't been in a place with bad interference. As much as I love single coils, I still get hum in certain places. I assure you, they are still susceptible to 60hz hum.
 
#19
DiabolusInMusic said:
easier to change to humbuckers than it is to add a dummy coil, the soloution for 60hz noise. This is how they make humbuckers, so it will also affect tone.
Click to expand...

Isn't it true that there's a difference in that the 2nd coil of a humbucker is magnetized and senses the strings, whereas a dummy coil is not magnetized so it only senses that darn hum in the environment? I imagine that means a dummy coil affects the tone much less than a 2nd string-sensing coil. I can see how it would lower the output compared to a single coil acting alone, but how much does it really affect tone?
 

Latest posts

Top Bottom
Back