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JCB RR1
11-09-2012, 02:06 PM
Im sorry if this turns out to be a long post, but I have no electrical knowlegde nor reference of a good luthir whatsoever.


I have a brand new KV2 which has a very loud buzz noise. I assume it is a consequense of bad grounding since the noise disappears as soon as I touch the strings, knobs or FR, but I could be wrong since I have absolutely no experience with the "electric" nature a guitar. The noise is present whether the volume knobs are turned up or down (both of them, V-V-T). It also sounds louder on some effect patches than others (the patch where the buzz actually sounds louder has a very tight noise gate).


As I said before I have no experience with this kind of issues, and I dont have any reference of a good luthier since I just moved here.


The only thing I though of was to remove the metal cover and then take pictures of the cavity so that maybe one of you guys with better understanding could probably guide me through the problem or try to identify it. I know it may be impossible, but I know you all know your stuff.


The cavity is covered by something that looks like plastic, I may be wrong here. I tried touching every pot, hum-selector, in order to possibly isolate a defective one, but every thing I touched just cancelled the buzz.


So here are the pics of the cavity, hope it might help.

https://dl.dropbox.com/u/16166510/2012-11-09 14.06.34.jpg

https://dl.dropbox.com/u/16166510/2012-11-09 14.07.00.jpghttps://dl.dropbox.com/u/16166510/2012-11-09 14.07.17.jpg

https://dl.dropbox.com/u/16166510/2012-11-09 14.07.31.jpg

https://dl.dropbox.com/u/16166510/2012-11-09 14.08.01.jpg

DalyTek
11-09-2012, 08:28 PM
Pics aren't working for me.

tomanyjacksons
11-09-2012, 08:43 PM
Same here, no pics.

straycat
11-09-2012, 10:19 PM
Check for a loose ground wire in the cavity, check the jack connections too.

warlok
11-10-2012, 12:41 AM
It buzzes even when the volume is turned down on the guitar, but stops if you touch strings/knobs/bridge? That seems strange.

JCB RR1
11-10-2012, 08:19 AM
Sorry about the pics, I moved them from their original location thus the link was no longer valid.


I just did what I should have done in the first place, try the guitar through different setups, with no noise gate or hard gate, directly connected to the amp.


The buzz is still there, even with both volume knobs turned completely down.


The only thing I can think of, merely out of logic, is that since the buzz doesn't depend on a specific volumen knob, nor a specific pickup, perhaps the problem lays on a common part of the circuit. That's all I can come up with now.


The last pic shows where the ground connection is. It's not the best connection but is feels tight.


I'm going to try and remove de plug connector and see if there something unusual there.


Hope you guys might find the problem. Thanks for your time.

straycat
11-10-2012, 09:19 AM
Try to screw the bundle of ground wires tighter in the body.
Check the ground wire to the trem claw too.

Scooter
11-10-2012, 10:57 AM
Check the amp and outlet too, fluorescent lights and older TVs can have an affect if they're close.

ginsambo
11-10-2012, 11:11 AM
My vacuum cleaner intereferes with the TV.

ginsambo
11-10-2012, 11:25 AM
Perhaps it might help if he plugged the guitar into the vacuum cleaner?

JCB RR1
11-10-2012, 01:11 PM
Try to screw the bundle of ground wires tighter in the body.
Check the ground wire to the trem claw too.


Checked both with no improvement.



Check the amp and outlet too, fluorescent lights and older TVs can have an affect if they're close.


I connected the guitar to the laptop using usb connection and still had the buzz.



Check for a loose ground wire in the cavity, check the jack connections too.


Again no change on the sound.


I checked the whole circuit following a circuit diagram from Seymor Duncan, I saw some differences but I'm not quite sure if that would be a standard connection with possible alternatives.


Anyways, thanks guys for your time. If someone has a different idea or might think about trying something else please let me know.

http://cdn.seymourduncan.com/images/support/schematics/2h_2v_1t_3w.jpg

decadence5423
11-10-2012, 01:16 PM
Once there is a grounding issue touching anything will ground you which causes the buzz to stop. Have you pulled the input jack and checked the wires and solder connections there? I've had two guitars with buzz issues and the problem was at the input jack.

DalyTek
11-10-2012, 01:29 PM
It's hard to tell from the pics, but it looks like the 3 pots are connected together by a black ground wire, and maybe also connecting to the switch, but I do not see where any of them are connected to the grounding screw.
Basically, each component (pots, switch, pickups, bridge) should have one (and only one) route to get to ground, which in the case of guitars is the sleeve of the output jack.
If any of these components does not have a good path to ground, it will hum. Likewise, if there is more than one path to ground, you will have a ground loop which will also hum.

If you have a multimeter with continuity checking, pull out the output jack and put one probe there, and touch the other probe to each component and check for continuity.

JCB RR1
11-10-2012, 01:53 PM
It's hard to tell from the pics, but it looks like the 3 pots are connected together by a black ground wire, and maybe also connecting to the switch, but I do not see where any of them are connected to the grounding screw.
Basically, each component (pots, switch, pickups, bridge) should have one (and only one) route to get to ground, which in the case of guitars is the sleeve of the output jack.
If any of these components does not have a good path to ground, it will hum. Likewise, if there is more than one path to ground, you will have a ground loop which will also hum.

If you have a multimeter with continuity checking, pull out the output jack and put one probe there, and touch the other probe to each component and check for continuity.

Thanks man for your help!!!

All four componets are conected, but they're not linked to the grounding screw. 3 cables end up at the grounding screw, and all 3 come from the pickups and the output jack as can be seen on the second pic of my first post.

AdRock
11-10-2012, 09:10 PM
Kind of a not so right way to do this, but it worked for me.

I had an issue like yours. I got a piece of wire and rapped on end around the ground screw. Then with the guitar plugged I.and buzzing I started touching components with the other end of the wire. I eventually touched an item and the buzzing stopped. It had a bad sauter joint.

DalyTek
11-11-2012, 09:32 AM
Thanks man for your help!!!

All four componets are conected, but they're not linked to the grounding screw. 3 cables end up at the grounding screw, and all 3 come from the pickups and the output jack as can be seen on the second pic of my first post.

That's what it looked like from the limited view I could get in the pics. You need to connect one (just one) of the pots to that grounding screw. That should take care of the buzz. You can do like AdRock said and take a wire, attach one end to the grounding screw, then touch the other end to one of the pots to test and see if the diagnosis is right. If it goes away, then you know we got the problem isolated and you just need to you need to permanently solder it securely in place, or have someone do it for you if you are limited in your soldering ability.