Buzzing Cab

[steveo33]

Gang,

I have a home-built 18" cab that's served me faithfully for 20 + years. I recently picked up a GK MB200 to gig the smaller places, and when it get the amp close to 3/4 max on the volume, I get a horrific buzz/vibration from the speaker on certain mid range notes, mainly the A string. I thought cracked cone, but that's not it. Tightend up the speaker, but still get it.

I can't remember what the cab can handle, is the MB200 too hot for it, or maybe something I can glue to get the vibration out? Maybe something loose in a baffle?

Thanks,
s33

[BassmanPaul]

Steve, if by 3/4 max you are referring to the volume control position it is quite likely you are trying to get more out of the amp than it has to give. Position of the volume knobbie has no connection to what the amp is actually putting out.

Edit: What is the impedance of your DIY 18 and what is the output of the MB200 at that impedance?

[RickenBoogie]

+1 to that all the way.

[BassmanPaul]

Just checked: the MB200 is 200W into 4Ω. If your 18 is 8Ω that equates to a bit over 100W into your cabinet.

[steveo33]

It's a 4 ohm cab. You think the amp is being pushed too much?
Have to get my guitard to calm down.

Thanks,
S33