"
I'm adding 2nd harmonics when using a tube.
Which for us is more pleasant than the 3rd from transistors."
Excuse my French but that ^ is largely bollocks. The type of distortion a device produces depends mostly on the circuit configuration rather than the type of active component.
A single ended stage will indeed produce more even harmonics (not just second) than odd but this is true whether it is a valve, transistor or FET. A balanced circuit, e.g the Long Tailed Pair IF very well balanced will tend to cancel out even harmonics. The PI in a push pull valve amp is another example but they are rarely that good at harmonic cancellation unless steps are taken to trim the balance at all frequencies. Such trimming is only seen in hi fi amps of yesteryear.
Where transistors do differ from valves is in their extended HF response and the generally low resistances in their circuits compared to valves, especially Triodes. Thus, distort a transistor and the harmonics extend way past 20kHz. A triode stage will start to droop at 15 to 18kHz. All that supersonic '***t tends to filter back into the audio band. Also, valves have massive headroom, tens of volts. Your wee transistor or op amp is done at 20V pk-pk often much less.
The other bit of "harmonic BS" refers to transformer "saturation" (they rarely do*) Distort a transformer and you get mostly ODD harmonics! (same with tape)
As Rob said, the audio world has gone daft.
*"saturation" occurs when a component, valve, transistor, transformer, is turned on so hard that it ceases to function, it becomes almost a short circuit. Thus a saturated component would virtually shut down the progress of an audio signal and in the case of a valve do it no good at all. But! This is a bit of audio BS "Lore" that we will just have to live with I suppose? Like that other bllx, "rms" watts!
Dave.
Is that sort of a two axis waveform scatterplot, amplitude vertical and stereo spread horizontal, with a mono signal? If so that's also doing a SLIGHT amount of stereo widening, it seems.
