Hartke LH1000

[Leftbass]

My Hartke LH1000 went off in rehearsal today. It didn't feel hot anywhere. Its in a 2U rack so I coudn't check it properly till I got home. After taking the lid off I couldn't find an internal fuse anywhere. This is a bit odd as its usually in line on the power input. Anyway has anyone had a similar experience with these amps? I'll be taking it to amp repair man tomorrow but thought I'd pick your brains first. Wall plug fuse okay too. I had it hooked up to an 8ohm hydrive cab

[Dood]

Hmmmm, nooo, I've not heard anything 'up' with the LH heads doing that. How were you connected to the cab? Bridged or dual mono config?

[Leftbass]

Cheers Dood, Bridged from the speakon socket. The cabs are rated at 1000watts

[MarkBassChat]

Have you checked directly below the power supply cord? The fuse is integrated with the power supply socket. You don't need to open the amp to check the fuse.

Mark

[Leftbass]

Yeah thanks Mark. My techie friend found it straight away. Looks like an output ttansistor has gone! May be more damage too. Parts on the way I'm told.

[steve-bbb]

is it worth getting the cab checked over too? is it possible for a dodgy connection somewhere inside the cab to affect the impedance and then change the power draw on the head?

[Leftbass]

Problem solved guys. If you hear something rattling around inside your amp be sure to get it checked out. Unfortunately with my amp being in a rack the faint sound of a rogue screw ( which by the way did not even belong in the amp! ) moving around went undetected until it bridged between chassis and transistor. All repaired now though and ready to do some demolition work I mean play sweet music.

[MarkBassChat]

This is very funny - few years ago I was fixing HA3500, which had exactly the same problem; a screw (also not belonging to the amp) shorted a transistor from the power amp to chassis. I had to replace several transistors.

Mark