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Polytone Hum Problem

Posted: 24 Apr 2008 6:54 pm
by Larry Beck
I just picked up a Polytone Mini Brute off eBay. My problem is hum. I have a new guitar with Wallace True Tones. The signal chain is straight out of the guitar and into the amp. No volume pedal or other device is used.
When I put a Six string on the amp using the same cord the hum goes away. It is dead quiet. I have tried this with humbuckers and single coil six string guitars and get no hum what so ever.

The only thing that results in hum is the steel.

Here's the oddball: When the steel is run into another amp (I tried 3) does not hum.

A single cable was used for all comparisons. What's going on?

Hum

Posted: 25 Apr 2008 1:30 am
by Curtis Alford
I would think from you discription of your hum, the proble is a ground problem with the guitar wiring.
Is the pick-up grounded? Is there a volume control and tone control pots on your guitar.There needs to be a continous ground from the bridge(changer) to the out-put jack.Check the cap on the volume & tone pots that they are good and no cold solder joints on any of the wiring.If this is a single coil you may need to switch the wiring on the coil.(verify the polarity of the pick-up coil)
E-mail me if I can help.
acurtisalf@aol.com

Re: Polytone Hum Problem

Posted: 31 May 2008 7:26 pm
by Steve Hotra
Larry Beck wrote:I just picked up a Polytone Mini Brute off eBay. My problem is hum. I have a new guitar with Wallace True Tones. The signal chain is straight out of the guitar and into the amp. No volume pedal or other device is used.
When I put a Six string on the amp using the same cord the hum goes away. It is dead quiet. I have tried this with humbuckers and single coil six string guitars and get no hum what so ever.

The only thing that results in hum is the steel.

Here's the oddball: When the steel is run into another amp (I tried 3) does not hum.

A single cable was used for all comparisons. What's going on?
I'm experiencing the same issue with my pedal steel and this amp.
I'm borrowing it from a friend & it does seem to pick up the single coil hum.
When I put my POD X3L into the chain, the hum was reduced.
Ground issue?

Hum

Posted: 31 May 2008 7:56 pm
by Curtis Alford
When you touch the strings or the bridge does the hum stop or lesson? I have single coils on my 6 string guitar and on my MSA. I am grounded from the bridge to the jack. The ground in continous from the bridge to the pots( all of them) and to the out put jack. One common ground wire. One strand of wire from the either the core or the shield touching the other will give you a hum. It is not a cycle hum it is a short that is not sever enough to completely ground out the signal.
If they are grounded in this manner you will have to be closer than two feet from your amp (even if it is turned up) to get a slight hum. You would not be playing that close to your amp.
IMOP
Curtis

Re: Hum

Posted: 1 Jun 2008 5:02 pm
by Steve Hotra
Curtis Alford wrote:When you touch the strings or the bridge does the hum stop or lesson? I have single coils on my 6 string guitar and on my MSA. I am grounded from the bridge to the jack. The ground in continous from the bridge to the pots( all of them) and to the out put jack. One common ground wire. One strand of wire from the either the core or the shield touching the other will give you a hum. It is not a cycle hum it is a short that is not sever enough to completely ground out the signal.
If they are grounded in this manner you will have to be closer than two feet from your amp (even if it is turned up) to get a slight hum. You would not be playing that close to your amp.
IMOP
Curtis
My hum does lessen when I play.
I realize that my pickup is single coil, too.
I experience this, with my Fender Nashville B bender.
But its all good... once I start to play, the hum disappears.
Thanks for your info.
Steve

Posted: 3 Jun 2008 4:50 am
by Eric Philippsen
This probably isn't the cause of the hum you're experiencing but I thought I'd mention it anyway. I have had several Polytones. One Minibrute I bought cheap had a hum that I traced to, get this, the reverb pan being turned around 180 degrees within the cabinet. Someone had worked on the amp and reinstalled the reverb pan with its small transformers pointing up to the chassis rather than the bottom of the cabinet.