Question about buzzing cab

You may be pushing it too hard, either with sheer power, or low end eq. Either way, the cabs rating is it's thermal limit, not what it'll actually do. Most cabs will get you halfway to their rating before giving out.

 

Sometimes things shake loose. And sometimes the speaker it's self could be the problem. I once had a buzzing in my cab from the crossover shaking loose and over heating. Cracked circuit board.........

 

Possibly an overheated/blown speaker. Take the grill off and very carefully push each speaker in and out, listening closely for scratchy sounds. If you hear noise, the speaker is dead and needs to be reconed or replaced.

 

Moot, as the cab thermal rating is probably at least twice what the drivers can handle before exceeding their excursion limits. If there's nothing physically wrong with the cab try turning down the volume and/or the bass EQ.

 

Your new amp might have more output at infrasonic frequencies (below the enclosure's tuning). If the cabinet is a vented system, you have to be careful of that. When you drive a speaker (either a bass cab or a sound reinforcement/PA box), below its tuning frequency, it causes the woofers to move past their safe excursion capability. Try backing off the low EQ and see what happens.

 

That tells me that the VT is the problem.

 

Thread locker on all the fasteners.. move all TNuts to socket head cap screws.. layer of foam/sealant around all of the handles etc.

 

If you can, take the grille off the speaker and watch the drivers while you play. If they move too much, move erratically or don't move at all, then you'll find the problem

 

i have a similar problem.
cab buzz.
if i press down anywhere on the baffle it goes away.
happened out of nowhere. worked fine, then the rattle appeared.
its a chinese built ampeg b200r cab & those have a history of weird shakes and stuff.
don't know if its worth trying to find someone and pay to check it out or cut my losses.