VTL MB450 power tube choice

Bought a nice pair of MB-450 monoblock amps that need to be re tubed. One bad tube shorted the screen resistor which I have repaired.  This is the manual bias model.

I know VTL frowns on anything that is not bought thru them and anything other than 6550 used in this amp, however, I would appreciate any input from MB-450 owners on their preferences for power tubes and why.

Scanning archives has nothing recent.



I have VTL 450MKII amps and currently use Gold Lion KT-88’s. My reason is pretty simple, they sound the best with my speakers of choice. I have a full set of Winged C 6550 that I compared and prefer the KT-88’s. Since that comparison I’ve not felt the urge to audition other brands of tubes.

Thank you for the opinion.  I have come to the same conclusion, especially after reading Kevin Deal saying that make of the last 6550 tubes made were not as good as the earlier ones

My speakers are SoubdLab Dynastat, about as big as this room can handle, and I am very fond of their sound using another amp with 12 6L6GC Sylvania tubes and M8137 drivers.

The VTL MB450 I bought to help a friend in a Divorce, so I will give the beast a try.with the KT88s