picture shows a pair of Kl V 502 amps in the Eurodyn rack with their
control unit, the Kl VZ 502a. The unit at the bottom is a Kl Q 509
rectifier for the tone lamp.
Regarding the input sensitivity and the tone controls, the 502 amp
is an integrated amp. When used as power amp, the first ECC40 tube
is unnecessary and the input signal can be fed directly into the
second ECC40's input grid. Please be aware that a coupling cap is
needed when doing this.
If 12 watts are enough for your speakers (and it should be enough),
convert the tetrode connection of the EL34s to triode operation. I
use a 15 Ohms resistor to connect the screen grids to the plates.