Was mir da noch einfällt....
einfach nach niedrigem Klirr (THD) einstellen ist auch nicht der Weg, sondern lieber nach Gehör....
weil
manche Effekte laut Literatur erst ab ~ 6khz aufwärts relevant werden, der übliche 1 khz Sinus hier nicht viel aussagt.
THD sowieso relativ sinnfrei ist ohne Angabe des Klirrspektrums....
K2 hört man erst ab ~ 3%, ab 90dB soll das Ohr selbst schon ~ 10% Klirr auf K2 produzieren und Lautsprecher haben eh schon mindestens ~ 0,5% K2 (leise gespielt...)
Während ungeradzahlige Harmonische, gerade K7, offenbar bei sehr niedrigem Klirrgrad wahrnehmbar sind...
Übernahmeverzerrungen erzeugen viele höhere Harmonische inclusive K7.
Test CD mit Klirr (K2,K7) usw...http://www.stereophile.com/con…is-test-cd-2-tracks-20-26
"So what is does THD mean? Not much. I read an interview with Rupert Neve were he said that he actually built a 2nd harmonic distortion generator (cos 2nd harmonic can have some pleasing effects) and some people had to add 5% before they could hear the effect! Whereas at the 7th harmonic (which is the most unnatural) you could have 0.0001% distortion and it would still be irritating."
und
"Distortion of a musical signal in analogue systems usually involves the addition of new harmonics to frequencies strongly present in the original -- a process which can have desirable effects in some circumstances. Second-harmonic distortion (where the harmonics generated are an octave above the original frequencies) is obviously musically related to the input signal, and is not very noticeable even at relatively high levels. In fact, most people can barely hear 2 or 3 percent of second-harmonic distortion, and you have to raise it to about 5 percent before it becomes audible. Even then, it simply adds body to the original signal, making it sound fuller.
Third-harmonic distortion is rather more audible, but at an octave and a fifth above the original is still strongly related to the pitch of the input signal, and still very musical. This makes it very useful for enhancement purposes, although having too much at the low end can make your music start to sound muddy. The fourth harmonic is two octaves above the original, and fifth-harmonic distortion is still comparatively benign, but does give a metallic quality to the sound. By the time you get to the seventh harmonic (which is not musically related to the original), however, even a tiny amount can sound very harsh with the wrong material.
The main difference between the sounds of valve and solid-state (transistor and integrated circuit) amps is that the distortion generated by valve circuits consists mostly of second and third harmonics, and is thus highly 'musical'. Solid-state designs use large amounts of negative feedback to get distortion down to extremely low levels, but what remains tends to be spread out across the frequency spectrum and include high-order harmonics. The human ear is far more sensitive to high-order harmonic distortion, and some people can hear seventh-harmonic and higher distortions even at levels of 0.001 percent and less."
Michel