Markbass tube head startup problem
 

Hello,

I'm experiencing a recurring issue with my Classic 300 amplifier:

http://www.youtube.com/watch?v=hmafE...eature=mh_lolz

This video itself and the description should explain everything, but basically I'm unable to start up my amp. It has power running through it because it lights up, but when it gets to the "auto-biasing" phase, part of its schtick of having a microprocessor, it freezes and nothing else happens. When I look inside the amp from the front, only one preamp tube appears to be glowing; the 3 other ones along with all 6 power amp tubes are cold, even though I purchased it quite recently, albeit used, but I thought that part of the amp's schtick is the microprocessor letting you know when the tubes need replacing or which ones are faulty, despite the fact that, as I've said, I've only had it for a short period of time.

The shenanigans involved with merging analog and digital technologies aside, any advice and/or tips for solving this predicament would be greatly appreciated!

Cheers!

Typically all of the tubes are fed by the same filament supply. If some are lighting up and others aren't, the most likely root cause is the filament wiring has come loose. And if the tubes are cold, then the auto-bias will probably detect that nothing's happening, and give up.

Sounds like a trip to Guitar Center is in order to see if they will provide you with a warranty replacement.

Chances are, fix the filament supply, and the microprocessor schtick will come back to life.

You have 30 days to return it. 60 if you bought the Pro Coverage.