AC line noise and voice coil going bad???

[ampbldr2]

Couple things

1. OK I've monkeyed with my Celestion V30 and G12H speakers for years between cabinets and amps and now noticing some strange vibration noise when playing clean. There are no rips or dirt in the cones. I inspected it closely.

How can i prove the voice coil is going bad?

2. I think I am getting ac line noise (Dirty power) coming into my amps and figure I'd ask what is a good cheep or not so cheep solution. Power conditioner going to solve this? I have tried different outlets and still get a good amount of noise so I figure it is ac line noise.

How can I be sure ??

[Structo]

Well, in the past when I thought a speaker was going bad I would carefully press down on the cone near the dust cap with my fingers spread evenly around it and feel it to see if there was any voice coil rub.

If it does rub then it's only a matter of time before the coils start to short across each other or completely rub through and open.

[Gibsonman63]

I recently picked up a Furman Power Pro plus or something like that. They have about a half a dozen similar rack units for power conditioning. I paid about $150 for it. In the studio, the difference is noticable.

Just for grins, you might invest $20 in an outlet tester from Home Depot or Lowes. I bought on with indicating lights to tell you if it wired correctly and if not, it tells you what it wrong with it. I found one plug in my studio with the hot and nuetral swapped.