SVT4PRO just quit working...HELP!

[stevenkh]

I have a USA made Ampeg SVT4PRO that just "failed" today...

I powered it up, hooked up the bass, turned off the mute and started to turn up the master volume and...as I did the limit light started to flicker and then went to a steady on. At no time during that process did any sound come out of the cabs.

I hit a string and a very faint sound that was mostly distorted came through.

I turned it back down...checked everything that I could think of...tried again...same result. It hasn't worked since.

Checked bass and cable by using on different amp and everything was ok, so I believe the problem is with the SVT.

Never had anything like this happen before...ANY IDEAS???

[spaz21387]

are you sure the speaker cable was plugged into the right speaker output? the svt 4 pro does have alot of jacks back there...

[stevenkh]

yes...tried all jacks for ch. A and B, thinking that one might have gone bad or that one side of the amp might have failed.

same issue on 1/4 inch jacks and speakon jacks...tested cabs and spkr cables with another head and they too are working great.

[B-string]

The 4Pro has preamp tubes doesn't it? That would be the easy and cheap place to start.

[B-string]

Plug your bass into the effects return jack(s) to check if the power amp(s) are okay.

[stevenkh]

put in new tubes and same result...tried effects return...still nothing. I guess its off to the shop???