These are serious tubes - the DC plate voltage can run as high as 1,500 volts. They throw a lot of heat and I'd hate to think how messy a tube failure might be.
At 40 watts I don't think they are running the tube anywhere near its limit, though.
I think these tubes running single ended top out about 40w.
10-26-2010, 01:49 PM
mlsstl
If you look at the datasheet, the tube is capable of 125 watts or higher plate dissipation (single tube) but the transformer on a SET must be able to handle continuous DC which explains the relatively low power output in relation to the tube's design capability. That said, there are some 805 amps on the market that go to 50 or 55 watts.
10-26-2010, 03:18 PM
Geoffcin
Yes, that's over TWICE what a KT88 is capable of! I don't know If I would want to run the rail voltages up too high though. 1500v DC is a sure trip to the mortician if you get in the way!