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Author Topic: Hum in position 2 on a strat, overall buzz  (Read 436 times)
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« on: June 29, 2008, 12:58:38 pm »

I started shielding two strats equipped with Texas Specials a couple of months ago, but then got busy and never finished them. I finally did so yesterday, and it appears that I got rid of some hum, although it is by no means silent. Using some insight from jjasilli as well as the guitarnuts web site,  I shielded the cavity with conductive copper tape, and basically have all the signal grounds tied to the ground lug of the volume pot, which is then connected with a single conductor shielded wire to the ground lug of the output jack. I have the bridge assembly grounded to the body of the volume pot. I then connect the body of the volume pot to the ground lug of the output jack using the shield of the aforementioned signal ground wire. Thus, I have the chassis ground and signal grounds tied together at the output jack (at some point they have to be connected, I presume).

I also have a shielded wire running from the middle lug of the volume pot to the hot lug of the output jack. The shield is grounded at the output jack, but then cut off and left unconnected at the volume pot end.

1) Although I appear to have eliminated some hum, it is certainly far from silent. I am assuming it's is not possible to get it completely silent with the Texas Special pickups. I still have an annoying buzz which goes away only when I touch the bridge or output jack with my hand (both of which are at chassis ground). Is this buzz a problem that can be eliminated, or is this to be expected even after proper shielding has been done?

2) On my one strat, positions 2 and 4 have no hum, which is what one would expect (it still has the buzz issue, though). On my other strat, however, which is wired identically and also with Texas Specials, only position 4 (neck and bridge) eliminates hum. To me, that means both the neck and middle pickups are ok. I am wondering if perhaps the bridge pickup was done incorrectly when manufactured, but I am not sure exactly how to check and/or fix this. Is it just a matter of reversing the wires, or is there an inherent flaw with the way the magnets were oriented, or possibly something else?

Thoughts anyone?
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blues man
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« Reply #1 on: July 18, 2008, 09:14:18 pm »

I have a 69 reissue thin line telecaster (mexican made) and the pickups are the noisiest pickups ive ever heard. It's got  good blues tone though, as long as you keep your finger some where touching the strings or bridge. I feel your pain. Sounds like you wired it right. I'm going to change out my pickups to quieter ones it drives me nuts good luck.
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« Reply #2 on: July 19, 2008, 12:23:27 am »

* If you have a noticeable improvement in noise reduction, that may be as good as it gets!  (For further reduction in audible guitar noise, you may need a louder drummer  ;D  )

*  If touching/not touching the strings makes a difference, that may indicate a grounding issue.

*  If a 2-PU position does not yield hum cancellation, try reversing the wires of one of those PU's.
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« Reply #3 on: July 19, 2008, 07:34:15 am »

If these are the texas Noiseless pickups, they are pretty good, I had a strat with them and they are quite quiet compared to straight up single coils.  What are you plugged into?  Does it have a proper grounded plug?  Do any other guitars have this hum problem when using the same amp, cable and household plug?
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« Reply #4 on: July 19, 2008, 04:09:27 pm »

Texas Specials are not noiseless pickups, and they will always have some noise.  There is no way around that.  Shielding helps, but it is not a 100% solution.  I haven't heard the guitar, of course, so I can't say for sure, but you may already have it as quite as you are going to get without going to some form of humbucking pickup.  You could try a dummy coil, but they change the sound of the guitar in a way I'm not fond of. 


Gabriel
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« Reply #5 on: July 21, 2008, 07:59:45 am »

Does your notch position 2 (with the hum) sound correct? I guess I'm wondering if perhaps one of the tabs on the switch is being grounded out to the copper foil shield in the cavity. I put black electrical tape in the cavity under the switch after I shielded my strat to try and prevent the switch shorting out.
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