Ampeg Svt 1540 HE Distorting

[ShenanigansBass]

I have an Ampeg Svt 1540 HE cab with an Ampeg V-4 head. This is an amazing amp and sounds excellent, but this set up can not go past 12 o clock without distorting and is pretty loud, but not loud enough. I know for a fact this amp can get louder because I used my head on a regular ampeg 8x10 and it worked fine cranked up. If you have any idea how to fix this problem that would be amazing.

 

[JimmyM]

Maybe check for a blown speaker? Push gently on the cones and feel for rubbing in the voice coil. You'll definitely feel it if it's blown.