[BrendaAnnD]

Did some performance testing on the finished channel tonight. Interesting results.

Using my scope and 8 ohm speaker (steering clear of the resonant points of the speaker), I got 20V peak to peak whether I used program material or my HP audio generator, before clipping began on the bottom half of the waveform. This gives me 50W p-p. 

Using the same speaker and instead using a 1Mohm DMM, at the same point I got 5.4V RMS, which comes out to about 3.6W RMS.

Using the following specs for my output tubes, it says I SHOULD get about 6.5W out with the voltages in this amp, which match the highlighted section almost perfectly.

I'm confused. :/