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[angopop]

Hello, I just moved to a new place and upon plugging in my amp and guitar (old single coil Harmony guitar) I've got a ton of hum and buzz.

Guitars with humbuckers are fine, but this guitar worked fine in my last place, so I figure it's something in the new place.

Upon a buddy's recommendation, I installed a ground lift adaptor, and attached a piece of wire from my bridge to my pickups, which seems to help, but I've got to find the right position in the room while holding the guitar to minimize the interference.

I'm thinking of calling in an electrician.

Does anyone have any suggestions or idea how extensive this might be to fix?

BTW - I already tried different plugs in the house, as well as unplugging every other electrical device in the place, to no avail

Thanks,
Arthur

[John Roberts {JR}]

What kind of lighting?

JR

[Andy Peters]

angopop wrote on Wed, 09 March 2005 14:40

Hello, I just moved to a new place and upon plugging in my amp and guitar (old single coil Harmony guitar) I've got a ton of hum and buzz.

Nature Of The Beast.  My '65 Jaguar does this in different places, too.

Quote:

Upon a buddy's recommendation, I installed a ground lift adaptor

On your amp's power cord?  Punch your buddy in the nose for recommending something that a) won't solve the problem, and b) could kill you.

Quote:

and attached a piece of wire from my bridge to my pickups, which seems to help

Attach the wire between the bridge and the guitar ground (the sleeve of the 1/4" connector).

Quote:

but I've got to find the right position in the room while holding the guitar to minimize the interference.

Is there a radio station nearby?  Are their any fluorescent lights?  Dimmers?

Quote:

I'm thinking of calling in an electrician.

Call a luthier.

Quote:

Does anyone have any suggestions or idea how extensive this might be to fix?

You could try having the guitar's electronics cavity shielded.  That might work, but the usual suspects are the pickups.

--a

[Ivan Beaver]

Try making a directional guitar cable.  It is very important which end is which-so mark it.

You will need 2 good quality 1/4" plugs and good quality shielded mic cable (2 conductor + shield)   It needs to be flexable for use.

On the guitar end hook up the hot wire of the mic cable to the tip and the cold (low) of the mic cable to the ground of the 1/4" plug.  MAKE SURE the shield of the cable is not hooked up to anything or touching anything!!!!! on the guitar end.

On the amp end hook the hot wire to the tip and tie BOTH the low and the shield to the ground of the 1/4" plug.

The way this works is that the hot and cold wires provide the path for the signal to flow, and the shield carries any interferance current to ground-assuming the amp is grounded properly.  On a normal guitar cable, the shield is also a current path for the signal and the noise gets added to the signal.  

I have seen this work with great results and also with minimal results-so give it a try.

Ivan Beaver

[John Roberts {JR}]

One consideration might be cable capacitance. I would be careful about making such a cable too long and/or with high C cable. Otherwise it will be helpful at reducing pickup along the length of the cable.

JR

[Al Zara]

Andy Peters wrote on Wed, 09 March 2005 17:21

Quote: but I've got to find the right position in the room while holding the guitar to minimize the interference. Is there a radio station nearby?  Are their any fluorescent lights?  Dimmers?

How about a beer sign??

Andy Peters wrote on Wed, 09 March 2005 17:21

Quote: I'm thinking of calling in an electrician. Call a luthier. --a

 How true!!!

Al-

[Kevin Unger]

Sorry to bump an old thread, But I've got nearly the same problem myself.

Gear used:
-BSS B-Max preamp
-QSC RMX 2450

Both plugged right into the wall outlet, which is properly grounded. I am on the 2nd story of the house (3rd, if you include the basement all the wiring's in.) I'm also located right down the street from a radio station

Everything, no matter what combonation (even when the bass guitar is unplugged; the cable itself will still pick up RF, and have a nice buzz to it. Cable is brand name, and nearly brand-new.

Would something along the lines of an RF choke/ferrite core help at all? if so, any suggestions?

[Andy Peters]

Kevin Unger wrote on Tue, 15 November 2005 21:03

Sorry to bump an old thread, But I've got nearly the same problem myself. Gear used: -BSS B-Max preamp -QSC RMX 2450 Both plugged right into the wall outlet, which is properly grounded. I am on the 2nd story of the house (3rd, if you include the basement all the wiring's in.) I'm also located right down the street from a radio station Everything, no matter what combonation (even when the bass guitar is unplugged; the cable itself will still pick up RF, and have a nice buzz to it. Cable is brand name, and nearly brand-new. Would something along the lines of an RF choke/ferrite core help at all? if so, any suggestions?

Humbuckers?

-a

[Kevin Unger]

Andy Peters wrote on Wed, 16 November 2005 05:31

Humbuckers?

It's not the bass (It's EMG P/J style) It happens even when it's not plugged in

[Kevin Unger]

It seems my Bass actuall has a "suck" knob.


Could it be an improperly grounded pickup/pot? It IS connect to a non-humbucking J-style pickup.

cold solder joint, maybe?

[Steve Olsen]

I used to play a club that was right under a 50,000 watt AM radio tower. BOY did it suck. I ended up building filters for all my cables. They ended up with 50 kHz low-pass filter just before the amps. This drained the RF off but still allowed the phantom power to pass where needed.

Unbalanced cables got an inductor (680uH) in series with the hot and a 220pF NPO cap to ground (at the amp end). XLR's got the same treatment on both signal wires (pins 2 & 3). It worked like a champ. A couple of longer cables needed bigger caps (680pF).

Good luck,
Steve

[Kevin Unger]

Steve Olsen wrote on Thu, 17 November 2005 02:47

I used to play a club that was right under a 50,000 watt AM radio tower. BOY did it suck. I ended up building filters for all my cables. They ended up with 50 kHz low-pass filter just before the amps. This drained the RF off but still allowed the phantom power to pass where needed. Unbalanced cables got an inductor (680uH) in series with the hot and a 220pF NPO cap to ground (at the amp end). XLR's got the same treatment on both signal wires (pins 2 & 3). It worked like a champ. A couple of longer cables needed bigger caps (680pF). Good luck, Steve

thankyou.


an order to mouser will be made sometime soon...