trinityamps.com

here are my numbers:
plate volatage=350 volts
delta V across screen resistor=0.74 volts
cathode voltage=12.3 volts
150 ohm cathod resistor
100 ohm screen resistor

i believe these are all normal numbers based on the drawing.

therefore:
12.3/150 = 0.082 amps = bias current
0.74/100 = 0.0074 amps = screen current
350 - 12.3 = 337.4 delta V across tube
337.4*(.084 - 0.0074) = 25.2 watts or 12.56 watts per tube

so my question is, for seemingly normal numbers, we seem to be really pushing these tubes. am i off base anywhere here?
i really like the tone out of this amp. mixed with a THD cabinet i would take it over my rockerverb (at least for an all out cranked tone), so i am hesitant to change anything.

it looks like an additional 10 ohms on the cathod resistor would put me at 11.7 watts per tube.
just curious what others have seen.

thank you
Chris

by the way guys at trinity, you put out a very good product. i have swapped around gear over the years, but i still have this amp and plan to keep it.

whoops . . . maybe i should spell that dissipation

We go around this a couple of times per year but I can say, the design doesn't burn through tubes. On the TC15, we push them even harder and they survive.
I would not change anything. Your specs seem about right.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

You're at 105% plate dissipation. With cathode biased amps this is normal, you usually bias to around 100% or so.

Also with the NFB affect of a cathode biased output stage your bias actually drops when you play. So all is good in summary.

_________________
http://pdfelectronics.com

thanks guys

chris