"Ken Bessler" wrote in message
news:Pu6dg.27445$4H.6436@dukeread03...
Please visit this webpage - look near the bottom half of
the page. I'm trying to learn about amplifiers and have a
question about an AL-84 I'm messing with. I needed to
refer to an image of the schematic, so I put the image and
the question on my cox homepage:

http://members.cox.net/kg0wx/

The book for it calls for a minimum of 400 watts out for 100 watts of
drive.

http://bama.sbc.edu/ameritro.htm

They are not using a tuned input so to match the tubes to a 50 ohm driver
they are using the resistor as a lossey input. About 40 watts or so are
being dissiapated in the resistor and 60 or so are being used to drive the
tubes.