Sounds like you have dirty power - something on the same power circuit as your wall socket. Pool pumps, fridges, dimmer switches and a whole host of other domestic electronics introduce noise into the power.

A line conditioner will sort it out - basically a mains line filter with added protection and smoothing. Plug it into the power and all your audio equipment into that.

Hmmm. This sounds like some other form of interference other than the 50 Hz mains hum we get. As far as I can see there are 2 potential culprits: either other appliances connected nearby are sending noise into your mains system or there is an appliance nearby that is emitting magnetic or radio noise which is then getting into your amp. I find that if I turn the TV on when I'm playing, the hum from the amp is horrendous. Try turning as many other appliances in your house off sometime and then play through the noisy plug and see what happens.

edit:

Alan Ratcliffe wrote: Sounds like you have dirty power - something on the same power circuit as your wall socket. Pool pumps, fridges, dimmer switches and a whole host of other domestic electronics introduce noise into the power.

A line conditioner will sort it out - basically a mains line filter with added protection and smoothing. Plug it into the power and all your audio equipment into that.

+1 :-[

OK thanks that's all good advice. I'll wonder over to Communica just now and ask about line conditioner. Then over the weekend I'll have a bash at getting other appliances off.

I have a similar problem. Gurus, would a pedal like the Rocktron Hush have any effect on reducing said annoying frequencies, or is it designed for something else?

A noise gate or noise reduction will help (and the only things that really work against single-coil hum), but it's always better to get rid of a problem at the source than to try and filter it out later.

So then the line conditioner is the source fix? I just went over to Communcia and they dont stock those things although they know what they are. So where would I look for one - at a music store?

Thanks Alan.

Ray, when you find a place that can help out, could you perhaps post or PM me a price? :-[

Communica should have some line filters, which are the main component in a line conditioner. [quickly searches Interwebz]... here ya go...
http://www.communica.co.za/ProductListing.aspx?cid=a586297a99f7486c8200b35e54ddef89

The proper line conditioners used in musical applications usually have multiple outlets, each with it's own line filter.
I know the Samson rack models are available locally and are surprisingly cheap:
http://www.soundz.co.za/pSAPS10/Samson-Audio-Powerstrip-PS10--230V.aspx
http://www.soundz.co.za/pSAPB10/Samson-Audio-Powerbrite-PB10-230V-Power-DistributionConditioner.aspx
http://www.soundz.co.za/pSAPB10PRO/Samson-Audio-Powerbrite-PB10PRO-230V-Power-DistributionConditioner.aspx

Do you blow a lot of globes? Is there a fitting that you have to keep replacing the globe?

Not that I can think of. But you know, each time we have a thunderstorm this summer the electricity trips. And you turn it back on and you hear a bit of thunder and a strike or two and wham, down goes the electricity again. Used to be reare and now it's plenty.

Alan Ratcliffe wrote: Communica should have some line filters, which are the main component in a line conditioner. [quickly searches Interwebz]... here ya go...
http://www.communica.co.za/ProductListing.aspx?cid=a586297a99f7486c8200b35e54ddef89

The proper line conditioners used in musical applications usually have multiple outlets, each with it's own line filter.
I know the Samson rack models are available locally and are surprisingly cheap:
http://www.soundz.co.za/pSAPS10/Samson-Audio-Powerstrip-PS10--230V.aspx
http://www.soundz.co.za/pSAPB10/Samson-Audio-Powerbrite-PB10-230V-Power-DistributionConditioner.aspx
http://www.soundz.co.za/pSAPB10PRO/Samson-Audio-Powerbrite-PB10PRO-230V-Power-DistributionConditioner.aspx

OK thanks. I'll go over tomorrow and ask them what the story it's on their website. But I like the look of the Samson things. But they're all rackmount by the look sof things. Is there anything available that you can put on the floor or something?

Alan Ratcliffe wrote: Communica should have some line filters, which are the main component in a line conditioner. [quickly searches Interwebz]... here ya go...
http://www.communica.co.za/ProductListing.aspx?cid=a586297a99f7486c8200b35e54ddef89

The proper line conditioners used in musical applications usually have multiple outlets, each with it's own line filter.
I know the Samson rack models are available locally and are surprisingly cheap:
http://www.soundz.co.za/pSAPS10/Samson-Audio-Powerstrip-PS10--230V.aspx
http://www.soundz.co.za/pSAPB10/Samson-Audio-Powerbrite-PB10-230V-Power-DistributionConditioner.aspx
http://www.soundz.co.za/pSAPB10PRO/Samson-Audio-Powerbrite-PB10PRO-230V-Power-DistributionConditioner.aspx

there you go bringing up racks again.. :-[

guidothepimmp wrote: there you go bringing up racks again.. :-[

Nowt wrong with racks for those as knows how to use 'em. ? Standards of stage, studio and server, after all.

All you need to keep in mind with racks is that you must not get one bigger than 4-6 up and you must not want to fill it. Anything bigger is too heavy, not even mentioning cost. Mine is 6up, 5.5 full and moer se heavy, so I know...
BTW I have one of those Samson units in there and am no longer troubled by farting tube drive, electric fences or pool pumps. Gr8

Gearhead wrote: All you need to keep in mind with racks is that you must not get one bigger than 4-6 up and you must not want to fill it. Anything bigger is too heavy, not even mentioning cost.

+1. I made that mistake and moved to two 12U racks at one point. Great to have everything permanently wired up, but total monsters to carry around for live gigs. So I ended up with with a bunch of 4U.