Strategy 400/Bass 400 tubes

[FC Spoiler]

Maybe more luck here...
Hi all,
I've bought a Bass 400 last year, it came with 6 6550 tubes in it.
At high volume it sounded horrible distorted, so I tried 6 of the mesa tubes (6L6) from the Strategy in the Bass 400. Perfect sound
I've put the 6550 tubes in the Strategy 400 and.... Perfect sound
I haven't tried the 6550's back in the Bass 400 yet, maybe the tubes just needed a bit of wiggling to sound good (oxidation on the contacts)

I play about 3 hours a week, but that's going to change soon... From next week on, I'll have to gig at least once a week + practice.
So can the 6550 tubes be harmfull to the Startegy 400?
I play loud and the side with the 6550's is getting hotter than the 6L6 side. Both amps are original (fixed Bias) and the 6550's were matched to the Bass 400 by a tube guru.

All threads are nicer with a pic, so here's one (though there I'snt much to see)

The 6550's are on the left side of the Strategy (bottom amp) the rest of the tubes are Mesa STR 430's

 

[fishyfishfish]

I can hear that thing from my house! Make a quick call to Mesa and ask whats up. I usually call the Hollywood store because you don't get put on hold as much.

 

[FC Spoiler]

Thanx!
Mesa advises to get the 6550's out of the Strategy asap, can do serious damage...