My Descent is humming - cable?

[roberto]

Hi Guys!
Acquired Descent i recently. Has a bit of amp hum which gets worse when the signal cable is connected, probably partly a ground loop. No luck with Hum-X & cheater plug. Tried to open the back panel to see if anything was loose but there is another plate sealing the inside of the sub, can I remove it to get to the inside of cabinet to see if any wires are touching the amp? I am also looking at Jensen SUB-1RR as well as DCI spec ALH1 to get rid of ground loop. Has anybody had any experience with either of these units?
Thanks,
Vinod.

Hola...try a cheater plug on your Plasma TV. This will eliminate the hum. Hope this can help, happy listening,
Roberto.

 

[benleeys]

Hi Guys!
Acquired Descent i recently. Has a bit of amp hum which gets worse when the signal cable is connected, probably partly a ground loop. No luck with Hum-X & cheater plug. Tried to open the back panel to see if anything was loose but there is another plate sealing the inside of the sub, can I remove it to get to the inside of cabinet to see if any wires are touching the amp? I am also looking at Jensen SUB-1RR as well as DCI spec ALH1 to get rid of ground loop. Has anybody had any experience with either of these units?
Thanks,
Vinod.

Ahhh, another Descent i hum victim! I thought I was the only unfortunate guy. My brand new unit came with a horrendous hum, something like 75dB at 1ft distance from the cone, which refused to go away, even when disconnected from the system but with power on.

Vinod, the only way to get inside the box is to unscrew anyone of the 3 woofer units. Don't worry about ruining the screw threads because it's a nut and bolt affair, with the nut embedded in the baffle. Carefully lift the woofer out partly and unclip the 3 wires attached. Then lift it all the way out. The best way to do this is to first lay the speaker on one of its sides. Once opened, you might have to push aside the stuffing to view the wiring connections to the 3 amplifier boards. If, in the course of poking around inside, you find the clips to the woofers are loose, here's your chance to tighten them with a pair of pliers. Those in mine were.

In my case, the source of the hum couldn't be determined and I got a new replacement unit (with no hum).

Good luck.