Re: [ARSCLIST] Internet audio: What do you expect of it ?

["Steven C. Barr(x)" <stevenc@xxxxxxxxxxxxxx>]

----- Original Message ----- 
From: "Jerry Hartke" <jhartke@xxxxxxxxxxxx>
> Being rather ancient, I go back to tube amplifiers of the 1940's, and am
> confused about the reference to "solid state distortion." Does this refer to
> hard clipping when transistors are overdriven? Although tube amplifiers clip
> more gradually, they also introduce distortion in the process. Thus neither
> form of amplification should be overdriven.
> 
> Tube amplifiers are limited by their output transformer that matches the
> high output impedance of the tubes to a low load impedance. This transformer
> significantly degrades frequency and phase response, placing severe
> constraints on the amount of negative feedback that reduces the inherent
> distortion of the amplifier. I paid as much as $100 back in the '50s for a
> superior output transformer, and still struggled to achieve 20-20,000 Hz
> with 0.1% intermod.
> 
> Solid state amplifiers normally do not have output transformers, and thus
> can use greater amounts of negative feedback. This results in much lower
> distortion, better frequency (and transient) response, and superior damping
> than that achieved by most tube amplifiers. It seems that solid state
> amplification would be preferable provided that amplitudes stayed within
> their dynamic range (always necessary for fidelity.)
> 
> I do not disagree with those, including myself, raised on tube amplifiers
> and accustomed to their limited frequency response and somewhat higher
> distortion. Many of us like this "sound." However, we should not confuse
> this preference with faithful reproduction.
> 
Your last paragraph tells the story here...!

Fact #1: It is effectively impossible to build (at least at a saleable
price, anyway...!) an entirely-distortion-free amplifier. That is, it
MIGHT be possible, given dedication and a very large budget, to build
a single example of an amplifier which presents no AUDIBLE distortion
by careful selection of high-quality components...but virtually all
commercial equipment (which almost all of us use...!) reaches that
standard of perfection...!

Fact #2: As I note, vacuum-tube equipment is very much LESS likely
to be "audible distortion free"...! However, tube amplifiers (and
other equipment) present a much more pleasing type of distortion
to their listeners than do solid-state equipment...and this is due
to the ways that the two forms distort audio waveforms. Actually,
the "warm tube sound" beloved by many audiophiles IS distorted...
just more pleasantly so than solid-state distortion...!

As a (electrically amplified) harmonica player, I discovered this
through experience. I'm always seaching for a sound similar to
forties/fifties bluesmen...who used tube amplifiers (all there
were then...!?) and cheap mikes (all they could afford...?!) to
attain a "classic blues harp" sound. Needless to say, one CAN'T
get this sound from solid-state gear...!

I suppose one MIGHT be able to write a software program which
would generate the desired waveform...however, my digital
knowledge, while not entirely lacking, simply isn't up to
THAT task...

Steven C. Barr