[ARC5] 1626 tubes.

[Kenneth G. Gordon]

Supposedly, the difference between SS amps and toob amps is that the 
toob amps tend to emphasize the even harmonics, more akin to the way 
we hear live music, whereas the SS amps tend to emphasize the odd 
harmonics, and thus sound "funny" to anyone who really has 
experienced live good music.

I have always had a good ear: for music and other sounds. And I know 
that when the first SS amps came out, although to me the music could 
be made to sound "cleaner", it still sounded "funny".  Something wasn't 
quite right, and I really couldn't tell you what.

It is kinda like the difference in "sound" between a traditional wooden 
bagpipe chanter and drones vs the new ones made of Delrin, or some 
other hard plastic.

I once recorded on an oscilloscope tones played alternately on wooden 
and plastic chanters, and the difference was quite plain on the 'oscope.

I still have the photos. 

The wooden chanter had far more pleasing harmonics than the plastic 
one, while the plastic one sounded "harsh" or "brittle" in comparison. 
The tone from the plastic chanter contained far fewer harmonics, and 
those that it did have were quite a bit stronger than corresponding ones 
from the wooden chanter.

Ken W7EKB