Ashdown ABM users - anyone get hum on the Valvedrive?

boristhespider7 · #1 09-30-2011, 07:46 AM

Just got myself an Ashdown ABM 500 head i'm using with their ABM 210 cabs. When i turn the valvedrive on i notice a low hum when the master vol is above 11 o'clock, which gets louder as the master volume increases. Makes no difference whether the valvedrive is set to clean or grind. As soon as the valvedrive is switched off the hum disappears. The hums unneffected by any of the other controls on the amp.

Anyone else get this? Anything that i can do to stop the hum? Would a valve change fix it or is this part of having valves?

Sliderbass · #2 09-30-2011, 08:04 AM

Did you buy it new? If yes, bring it back! I had the same issue with my 500 EVO III and went through three new heads before I got one that didn't hum.

If you got it used and if you have any 12ax7's, try swapping the tube.

Either way, best of luck!

boristhespider7 · #3 10-06-2011, 04:01 PM

Contacted Ashdown and they reckon its probably a bad tube and should clear up with a new tube. Does that sound right to people? I'm a tube newb so not come across these issues before.

May just order a tube and swap it out to see if that fixes it, too much hastle to take my amp in and be ampless for a day or 2.