OK, the first think first. The second and the their images from the tope that were marked 2000Hz and 40000Hz are in fact 20.000Hz and 40.000Hz. I just lost a zero when I typed it. I have corrected the labels
Jim, it is a good question about the input waveform? I have no idea now and I will post it later on tonight. I have quite rudimentary and not very well performing generator and perhaps it does not have a proper output (thought I doubt). From a different perspective, why should we not see a lot of 2nd order distortions in output? It is SET, it should be this way. Perhaps later on I will run my distortion analyzer against the Melq …
Regarding the power. 28.5V RMS is was into 12R, as I usually do. I measured it precisely at calibrated scale just once to have an idea about the power. When I was looking at the frequency response I uncalibrated the scare juts to starch the wave exactly across the 10 dividers on the screen and then, running the frequencies up and down, I used only time/div to view the valve. I know, that you might consider this way of viewing is quite barbaric and I might agree with you but I did not care when it hit 3dB and I was not concern about the absolute numbers of the response. To me it is more important to get a FEELING of dynamic of this process. I usually set the max outs voltage on generator before the wave get clipped at 1000Hz and then moving up I observe how dynamic with whish amplitude goes down after 20Khz; and moving down, I observe HOW the wave get distorted under 30Hz. I had THAT feeling from my first excremental Melq and I was a little disappointed that this new Melq with 60W plate dissipation measure and sound so different and so poor. This current version with the lower plate dissipation (similar to the original Melq was) behaves and sounds and very similarly to the original Melq, although the original had very slightly more, 42W on plate.
Guy, yes, I post the 10K square wave tonight,,,
Romy the Cat
"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche