Humming like guitar isn't plugged in

[jmaf]

Vai is a witch. If he were alive in 1314 they'd have burned him at the stake along with Jacques de Molay.

[big_teee]

Vai is a witch. If he were alive in 1314 they'd have burned him at the stake along with Jacques de Molay.

Is that why the Noisy comes and goes?
Terry

[jmaf]

Is that why the Noisy comes and goes?
Terry

I'm afraid so, Terry. But we don't have grounds to say this is indeed witchcraft. It sure is not of this earth.

[Phil66]

Ok sarcasm over puleese.

Took Peavey Bandit Transtube into shop and MY cable. At maximum gain with gain boost on and guitar plugged into the High Gain input which is + 6bd and the volume on number 8 the hum was barely audible. Get home, with the amp set the same but the volume down to 2 the hum is as loud as pulling the cable out. The only way I can get it to acceptable levels is to use the Low Gain input. I'm putting it down to, and the shop has not had any influence on my decision, high output pickups that are built to a cost, ie, cheap and cheerful, the shop is still baffled at how it is so much different in my house to the shop. I was in fact embarassed when we plugged it all in, even the owner said he was hoping that it would hum like mad in the shop so they could at least hear it and get cracking on a fix, he has also had it through a JCM 900 on full tilt and it was as quiet as the Legacy.

I can live with it because at a nice level of gain, ie; number 7 without the boos there is no hum.

Very weird though.

Pil

[big_teee]

That is Strange.
Sounds like some kind of EMF Electrical interference of some kind.
I would start tripping breakers and turning things off.
Test it in the garage, and see if you can isolate to a Computer, Lighting, or some electronic device.
I play in my bedroom next to my desk, there is a computer, router, phone, flourescent light and a ceiling fan.
At times it really raises hell. Some guitars are worse than others.
Single coils really make noise.
Good Luck, and be sure and tell us what it is if you get a fix on it!
Terry

[Phil66]

It gets weirder. I took it downstairs, plugged it into some sockets that were only installed about 3 years ago, the hum was just as bad but touching the strings didn't silence it, it made it quieter but didn't remove it all together. Now then, I put the guitar down on the floor, touching the strings did absolutely nothing to the humming, it was there in all its glory.
Very strange eh?

[big_teee]

It gets weirder. I took it downstairs, plugged it into some sockets that were only installed about 3 years ago, the hum was just as bad but touching the strings didn't silence it, it made it quieter but didn't remove it all together. Now then, I put the guitar down on the floor, touching the strings did absolutely nothing to the humming, it was there in all its glory.
Very strange eh?

Pick a day no one is home and start flipping breakers!
T

[jmaf]

It gets weirder. I took it downstairs, plugged it into some sockets that were only installed about 3 years ago, the hum was just as bad but touching the strings didn't silence it, it made it quieter but didn't remove it all together. Now then, I put the guitar down on the floor, touching the strings did absolutely nothing to the humming, it was there in all its glory.
Very strange eh?

I've seen this happen when the earth wire on the mains network is not actually earthed and is picking up all sorts of noise and pumping it straight into the chassis. Try a cable where the 3rd pin has been cut(not recommended for use, just for testing) and see if the noise remains.

[big_teee]

How about it Phil?
Have you tried the breaker flippen test yet?
Also if you are electrically inclined, you could wire a receptacle right off the breaker box and test it there.
Another angle is to get a cheap receptacle tester, to see if your receptacles are wired correctly.
Your house isn't under large high voltage power lines of anything like that nearby?
Good Luck,
Terry

[Phil66]

If you have a Multi Meter that reads ohms, this is how to check to see if your Vol. Pots are working right.
Plug guitar cord into your guitar, No Amp.
Put selector switch on Neck Pickup.
Open vol Pot to Full Volume.
Check your guitar cord. Put one meter probe on Shield ground side and touch the other probe to the tip of plug.
Set your meter to Ohms and turn the scale so you can read at least 10-20k Ohms.
It should read around 7-8k Ohms.
Turn the volume off to no volume.
Now read the guitar cord again, and it should be a short circuit Zero Ohms.
Turn Selector Switch to Bridge Pickup, and repeat above.
You should read between 7.5-16k Ohms, depending on the pickups.
I suspect you will not read zero ohms with vol. pots turned off.
Let us know what you find.
Thanks
Terry

Hello Terry,

Finally I managed to get a tester. Now I don't even know what an OHM is other than the sound people make when meditating. The needle rests on the 500 ohm side of the meter and when I put the ends together it goes to the zero end on the right hand side. Ok, I get the same result on both when checking the plug on the lead, with the volume up it goes to 20 ohms and with the volume down it goes to around 500 ohms.

What does that tell you?

Cheers

Phil

[big_teee]

Hello Terry,

Finally I managed to get a tester. Now I don't even know what an OHM is other than the sound people make when meditating. The needle rests on the 500 ohm side of the meter and when I put the ends together it goes to the zero end on the right hand side. Ok, I get the same result on both when checking the plug on the lead, with the volume up it goes to 20 ohms and with the volume down it goes to around 500 ohms.

What does that tell you?

Cheers

Phil

Sounds like a Analog meter with a real meter and needle.
Haven't used one like that in years.
There should be different settings on the ohm scale.
Probably x1, x10, x100 etc.
If on Times x1 it should read close to full scale zero to 100ohms or so, when you turn volume down all the way.
You should be reading at the end of your guitar plug across tip and shield, with the other end plugged into the guitar.
When you turn the volume all the way up you should read 6000-85000 ohms.
You will have to change the scale to x10, or x100 to read that.
If you don't read close to zero ohms with the volume turned down, then the pot is bad or not grounded properly.
I'll be back on here later.
Terry

[Phil66]

Well I'm away now until Monday evening, it is an analogue meter the same as this one here

What should I do then?

Phil

[big_teee]

Well I'm away now until Monday evening, it is an analogue meter the same as this one here

What should I do then?

Phil

Just try it like I outlined in my last post.
T

[Phil66]

Just done it before we set off.

Each pickup individually with the volume up gives 14 ohms and with the volume down 1000 ohms.

With the pickup selector in the middle it gives 7 ohms with both volumes up and 400 ohms with both volumes down.

Phil

[Danelectron]

I'm afraid so, Terry. But we don't have grounds to say this is indeed witchcraft. It sure is not of this earth

Boooooo....