New Roadster owner - Problem

[coffeeman]

Bought 2 roadster head & cabs for the band - delivered 3 weeks ago - 240v UK. Amps are incredible but had a problem yesterday @ a gig with one unit.
Sound check was absolutely A1.
Put amp into standby
After 30 mins turned on for first set - nothing / nada - actually VERY slight sound coming from cab.

Today - checked thoroughly all the valves thru the other unit - all OK.

Out of nowhere once the valves were replaced the 'faulty' unit started working perfectly.

Now totally confused - we are not total newbies to valve amps - also have 'Park' Lead 50 combo / Engl Screamer & have had numerous Marshalls & Hiwatt units.

Any help would be appreciated. The Coffeeman

 

[Boogiebabies]

If it's using Mesa 12AX7 Chinese, I have blow about 5 of these. Once the amp is fired up and played the tubes heat up and they work fine.
When you go to standby or off, the glass on the V1 cracks, splits or just kills the tube. On the RK II it's behind the power transformer. when you hear a faint signal through the speakers it's usally the V1 preamp tube going down.

 

[barneyc4]

If it's using Mesa 12AX7 Chinese, I have blow about 5 of these. Once the amp is fired up and played the tubes heat up and they work fine.
When you go to standby or off, the glass on the V1 cracks, splits or just kills the tube. On the RK II it's behind the power transformer. when you hear a faint signal through the speakers it's usally the V1 preamp tube going down.

Do you recommend retubing the amp then?!
What tubes do you recommend for the Roadster?

 

[Boogiebabies]

It's just the V1 for some reason. That's the only Mesa Chinese I have had blow up on me.

 

[barneyc4]

What did you replace it with?

 

[Bullen]

The cracked tube thing happened to me too.

My Mark III suddenly wouldn´t work after putting it on standby. Checked the V1 tube and sure enough, it was cracked. Looked like a milk bottle had exploded inside it. But it was a Mesa branded russian tube, not chinese.