"RapidRonnie" wrote in message
...
On May 28, 2:08 pm, "Arny Krueger" wrote:
wrote in message
"In a word: YES...
"The answer is rooted in the harmonic content that the
device can pass or generate..."
There is no question that tubed power amps are inferior when it comes to
passing harmonic content. They are just too nonlinear and just too
limited
in terms of power bandwidth to compare with more modern alternatives.
As far as the generation of harmonic content goes, it is unclear why
maximizing harmonic content would even be desirable in a component of a
high
fidelity system. Furthermore, if versatile and powerful harmonic content
generation were desired, then the tools of choice would be from the
digital
domain.
Properly designed tube amplifiers have entirely satisfactory bandpass
and distortion characteristics. Passing frequencies above 35-50 kHz is
very undesireable in an audio amplifier. Ideally a shallow taper from
about 25 kHz and a drop at 50 or so is desireable.
**Bull****. Such a poor frequency response, will lead to a severely and
audibly compromised phase response. The human ear is very sensitive to phase
problems. A linear frequency response, which leads to a close to 0 degree
phase shift at 20kHz is desirable.
Many solid state audio amplifiers work well for RF in the 100-300 kHz
range. That is not a feature, it's a bug. The output transformer of a
tube amplifier beneficially throttles this extreme HF response.
**Bull****. The output transformer damages the frequency response of valve
amps. Valves are inherently high frequency devices.
--
Trevor Wilson
www.rageaudio.com.au