At 01:42 PM 6/6/02 -0700, Tim May wrote:
Someone said something earlier about tube/valve amps giving a boost to the high end, for older, hearing-damaged rockers.
Mr. Elloi wrote first about the fashion for "valve" audio amps and then mentioned that some yahoos listen with Dolby emphesis. I commented that the latter was for the old deaf. This is unrelated to the fashion for valves. I don't think the
frequency response has evern been an issue...tube amps are said to have
a "warmer" sound, and to have more odd harmonic distortion than transistor amps, but the frequency response of _any_ transistor or tube
amp is vastly beyond what even high-end speakers and headphones can typically deliver.
A modern solid state amp is essentially "flat" from 20 Hz to 20 KHz.
Yes, in the linear part of their operation. But its the *distortion* (large signal behavior) which differs ---tubes distort differently when "overdriven". I believe the difference when driven with a square wave is that tubes have a more RC-like output function, vs. a sharper (faster slew) transistor reproduction. One little known fact is that humans actually prefer a small amount of distortion in their listening. The THD of amps with a lot of decimal-zeroes, is a good technical spec (easily attainable, cheaply, nowadays), but is totally a marketing scam. First you can't hear the difference between .01 and .001 % THD, and second you prefer ~ .1% Now back to your regularly scheduled decay of civilization..