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Author Topic: Hum Issue  (Read 15559 times)

Shag101

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Hum Issue
« on: April 06, 2011, 11:54:40 PM »
Hey Guys,

I recently installed a MQ bridge replacing a warpig.  I have a MQ in the neck as well.  Gibson SG.

Im getting what seems to be 60 cycle hum from both pickups ( i think that is what it is)

When i touch the strings or any other metal part of the guitar..including pots and jacks...the noise does NOT get louder or lower.  It is just constant and will only increase when i move the guitar near my laptop, amplifier, or increase the gain on the amp. 
The noise also does not change in any way from neck, neck/bridge, bridge positions.

I know 60 cycle hum is normal with single coils but i never had it this bad with the queen neck..now i do.  The only thing i changed from the neck wiring is move cap from modern to vintage and upgrade cap from ceramic to orange drop. 

The hum is high pitched and lessens when i roll back the tone control on the guitar. 

With gain, it is crazy loud. 

The amp is a VHT special 6 combo.  Tone knob on middle and volume up 1/4.  No gain....and hum is pretty bad. 

Is there some tests I can do to see if i do have a wiring issue?  can i wire one pup directly to the input to see if the noise is still there? i have a multimeter if that helps.

thanks in advance!


 
Mississippi Queen Set = Gibson SG Standard
Warpig = '88 Charvel Model 1

Transcend

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Re: Hum Issue
« Reply #1 on: April 07, 2011, 06:33:03 AM »
this is just general p90 hum

You'll be getting it a lot more on the bridge as its higher output.

its the only thing i dislike about my MQ.

A noisegate should help you

Dmoney

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Re: Hum Issue
« Reply #2 on: April 07, 2011, 08:52:47 AM »
you didn't have the hum originally at the neck? but now you do?
and you only replaced the bridge pup?
So you should have only been soldering around the bridge volume pot apart from moving the cap between the middle and outer lug on the neck vol pot?

sometimes in these cases it's worth posting a picture. The only thing I can think of is a disturbed ground or maybe a bad joint.

darkbluemurder

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Re: Hum Issue
« Reply #3 on: April 07, 2011, 10:16:06 AM »
Hey Guys,

I recently installed a MQ bridge replacing a warpig.  I have a MQ in the neck as well.  Gibson SG.

Im getting what seems to be 60 cycle hum from both pickups ( i think that is what it is)

When i touch the strings or any other metal part of the guitar..including pots and jacks...the noise does NOT get louder or lower. 
 

It appears that there is a missing ground in your guitar. All metal parts should be connected to ground. Take a good DMM, put a cable into the guitar output jack and check whether there is continuity between the cable ring and all the metal parts of the guitar (pot backs, bridge, strings).

Cheers Stephan

Shag101

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Re: Hum Issue
« Reply #4 on: April 07, 2011, 12:58:24 PM »
Thanks Guys..

I did pick up some 22 gauge cloth wire to get free shipping last week..so since i have the day off tomorrow..i'm just going to rip out everything and rewire...
if i still have the issue..i will post up some pics...

i did not have this issue before when i just selected the queen in the neck prior to any mods.

thanks again...i'll keep you posted....
Mississippi Queen Set = Gibson SG Standard
Warpig = '88 Charvel Model 1

PhilKing

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Re: Hum Issue
« Reply #5 on: April 07, 2011, 02:52:58 PM »
Also make sure you don't have multiple path's to ground.  Pick one pot to ground everything through.
So many pickups, so little time

Shag101

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Re: Hum Issue
« Reply #6 on: April 08, 2011, 05:04:36 PM »
Hey All,

I re-wired the guitar and it is exactly the same.  Maybe a little less... Below is a pic of the wiring (yes I suck at soldering) and a link to a short video I made displaying the hum vs volume.  I'm guessing this is normal 60 cycle hum.  Maybe since I went from modern to vintage and noticed an increase in the high end...i also got an increase in the hum??? I used alligator clips so i was not paying attention to hum as i just related it to the clips..When all knobs were at 10, i noticed vintage had way more high end than modern..even though they should have been the same.

http://ge.tt/5cRBB8J

Again..Thanks for any input!
« Last Edit: April 08, 2011, 05:07:49 PM by Shag101 »
Mississippi Queen Set = Gibson SG Standard
Warpig = '88 Charvel Model 1

Dmoney

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Re: Hum Issue
« Reply #7 on: April 08, 2011, 06:35:07 PM »
I can't quite make out the switch wiring.
I guess the top middle lug is ground, and wired to the top of both volume pots, and the bottom with both contacts pushed together is wired to the output.

Originally, was this full of braided shield wire?

Shag101

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Re: Hum Issue
« Reply #8 on: April 08, 2011, 06:58:34 PM »
yea, when wiring it dawned on me that i should have got 2 colors of cloth wire.

the hot terminal on the output jack was the center of a braided wire (like pups)..it went from there to the bottom of the switch where both pegs are pushed together.  The braided part of the wire went from the ground terminal of the output jack..then soldered  to 3 pots.  The 3rd pots was then wired with regular 22 gauge pvc wire to the center pegs of switch...then to the last pot (4th pot).  
This was the stock wiring from gibson and I still had the same hum...(though not as loud as prior to cap move)...moved cap and have same hum braided or non braided..or maybe just coincidence

I wired it basically the same as stock..but did not use the braided...

The hot terminal of the output jack goes to the bottom of the switch (both pegs still pushed together).  The ground is a single uncut wire going from the ground of the output jack to a) bridge tone b)bridge volume c) top center pegs of switch d) neck volume e) neck tone.  In that specific order..I used a GB cutter to access the wire without actually cutting it...
The guitar ground is soldered to the neck volume pot.

The cavity has some grey paint in it, so i'm guessing its painted shielding...
« Last Edit: April 08, 2011, 07:11:15 PM by Shag101 »
Mississippi Queen Set = Gibson SG Standard
Warpig = '88 Charvel Model 1

St.James

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Re: Hum Issue
« Reply #9 on: April 09, 2011, 12:55:23 PM »
[
« Last Edit: April 23, 2011, 10:10:06 AM by St.James »

Shag101

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Re: Hum Issue
« Reply #10 on: April 09, 2011, 03:12:59 PM »
Thanks St James,  I might take you up on that offer if I cant figure it out.  I live in queens, just a hop skip to nyc... :D

I used my multimeter on ohms as a continuity tester.  I get anywhere from 0.2 - 0.5 readings.  No open ckt here.  Readings were taken between then output jack to the switch, pots, ground wire, bridge, stings, tuning pegs. 

no loss in volume and the tone is HEAVEN!!!

i notice if headstock is pointed at amp..hum gets louder.  if pups face the ceiling hum gets louder....i guess that is due to how the fields of the amp and pups are crossing each other.  One way the fields are going in same direction and the other they are cutting into each other more so more hum...(prolly just talking out my butt here..lol..)

im guessing this is just the nature of the beast.

did you look at my clip and can tell its not normal hum??

thanks
Mississippi Queen Set = Gibson SG Standard
Warpig = '88 Charvel Model 1

Dmoney

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Re: Hum Issue
« Reply #11 on: April 09, 2011, 03:16:02 PM »
sounds like its all good? your wiring looked right to me.
continue playing NYHC.

St.James

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Re: Hum Issue
« Reply #12 on: April 09, 2011, 03:45:51 PM »
 8)
« Last Edit: April 23, 2011, 10:09:35 AM by St.James »

St.James

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Re: Hum Issue
« Reply #13 on: April 09, 2011, 03:49:13 PM »
s
« Last Edit: April 23, 2011, 10:08:50 AM by St.James »

Dmoney

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Re: Hum Issue
« Reply #14 on: April 09, 2011, 03:54:20 PM »
isn't a standard tone pot wired as a treble bleed? in which case there are two in the photo he attached.