Hum noise from amp head

[LowdownRumble]

Ive only now noticed that my Eden head (or at least i think its the head) produces a humming/buzzing noise, but only when the output pot on my bass is turned up between 2/4 and 3/4. That is, when the bass is on full or completely turned down there's no unwanted noise. anyone got any ideas why its doing that?

[EdwardHimself]

This used to happen to me with the pots on my guitar. I found that sorting out some shielding for it solved the problem. At any rate, I don't think it's the amp that's the issue.

Edited November 19, 2011 by EdwardHimself

[Lozz196]

Why on Earth would you have your bass on anything other than fully on or fully off

I`ll get my coat.

[Mr. Foxen]

Dubious earth path in your bass.

[Billy Apple]

I would agree with Mr F. Does it get any quieter when you press your palm over the bridge?

[LowdownRumble]

Lozz196, because i like to turn the knobs on my bass
[quote name='billyapple' timestamp='1321742725' post='1442734']
I would agree with Mr F. Does it get any quieter when you press your palm over the bridge?
[/quote]

No it does not. The hum changes a bit when i fiddle with the speaker cable, so im thinking it might be a dodgy connection on the cab. How would one go about fixing a bad earth pass?

Edited November 20, 2011 by LowdownRumble

[Billy Apple]

[quote name='LowdownRumble' timestamp='1321747277' post='1442769']
Lozz196, because i like to turn the knobs on my bass


No it does not. The hum changes a bit when i fiddle with the speaker cable, so im thinking it might be a dodgy connection on the cab. How would one go about fixing a bad earth pass?
[/quote]

Maybe it's the cable itself is knackered, try using different ones and see if there is a difference. You will probably find it's a bad solder joint somewhere, and it's a process of elimination to find it. But often it will be around areas where there is movement, like jack sockets, inputs, power leads and plugs. Unless you are competent in your electrical know-how, I'd leave it to an expert. A good Luthier in your area should be able check the Bass, and will probably know someone who could have a look at the amp. My guy is in Berkshire, which is not a great deal of help to you in Norfolk, but I'm sure there are BC'ers around who can recommend someone in your area.

Here is a story for you...
Years back a friend of my cousins had a proper Arcade Grand Prix Racing game in his garage. You sat in the thing, and we had the door where you put the quid in open. If you stuck your hand round the back, you could pull a small lever that gave you free credit. I put my hand in, and the next thing I knew I could not release my grip from something that felt like my arm was going through a grinder, I was also on the floor in spasms. My cousin managed to boot my arm free from the machine, and luckily I was OK, but very shaken.

Be warned, do not f*** with electricity... Find a professional and let them deal with it.

[Musky]

[quote name='Mr. Foxen' timestamp='1321741862' post='1442724']
Dubious earth path in your bass.
[/quote]

This sounds right to me, possibly caused by reversed polarity in the wiring somewhere. The volume pot would still work, but it wouldn't be shunting the earth to ground when you turn the pot down.

[LowdownRumble]

[quote name='billyapple' timestamp='1321750890' post='1442802']
Here is a story for you...
Years back a friend of my cousins had a proper Arcade Grand Prix Racing game in his garage. You sat in the thing, and we had the door where you put the quid in open. If you stuck your hand round the back, you could pull a small lever that gave you free credit. I put my hand in, and the next thing I knew I could not release my grip from something that felt like my arm was going through a grinder, I was also on the floor in spasms. My cousin managed to boot my arm free from the machine, and luckily I was OK, but very shaken.

Be warned, do not f*** with electricity... Find a professional and let them deal with it.
[/quote]

Ive had my fare share of first hand experiences When i was a kid i stuck a key into a wall socket. The key almost melted in my hand as i just stood there getting blasted with electricity

Needless to say, illl have someone who knows his stuff have a look at it

[Billy Apple]

[quote name='LowdownRumble' timestamp='1321824453' post='1443571']
Ive had my fare share of first hand experiences When i was a kid i stuck a key into a wall socket. The key almost melted in my hand as i just stood there getting blasted with electricity

Needless to say, illl have someone who knows his stuff have a look at it
[/quote]

I read back my post today, and hope I didn't come over as a little patronising, I'm sure you know your onions. Hope you get rid of that Hum quick-time.

Best wishes,

Apple

[bertbass]

A dodgy speaker cable would either work or not, it wouldn't cause a buzz. I'd suggest that the pot on your bass is shagged and replace it or just turn it up full and leave it alone.