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

[Robert J Hodge <rjhodge@xxxxxxx>]

-----Original Message-----
From: Robert J Hodge 
Sent: Wednesday, December 19, 2007 9:25 AM
To: 'jhartke@xxxxxxxxxxxx'
Subject: RE: [ARSCLIST] Internet audio: What do you expect of it ?

When the transistor was first marketed as an amplifying device, it
suffered from its' ability to act like a switch- that is to say until
the signal at the base became high enough to make it conduct. Germanium
and early silicon based transistors had this anomalism.
I had a couple of those early amplifiers and got rid of them after
trying to live with them. At low signal levels, they sounded terrible.

As with anything of an early design, this problem was overcome with
better transistor design.

I have used mosfet power amplifiers now for many years and will never go
back to the tube units. Of course, even overdriving a mosfet unit will
sound terrible! Clipped is clipped.

I keep the tube units around, just in case. 

Bob Hodge
 
 -----Original Message-----
From: Association for Recorded Sound Discussion List
[mailto:ARSCLIST@xxxxxxx] On Behalf Of Jerry Hartke
Sent: Wednesday, December 19, 2007 6:40 AM
To: ARSCLIST@xxxxxxxxxxxx
Subject: Re: [ARSCLIST] Internet audio: What do you expect of it ?

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.

Jerry Hartke

> -----Original Message-----
> From: Association for Recorded Sound Discussion List
> [mailto:ARSCLIST@xxxxxxx] On Behalf Of Steven C. Barr(x)
> Sent: Tuesday, December 18, 2007 11:06 PM
> To: ARSCLIST@xxxxxxxxxxxxxxxx
> Subject: Re: [ARSCLIST] Internet audio: What do you expect of it ?
> 
> ----- Original Message -----
> From: "Don Cox" <doncox@xxxxxxxxxxxxxx>
> > Hello Steven
> > On 18/12/07, Steven C. Barr(x) wrote:
> > > ----- Original Message -----
> > > From: "Roger and Allison Kulp" <thorenstd124@xxxxxxxxx>
> > >> I see it as a latter day version of the all-tube FM tuner,rather
than
> > >> the CD/phono amp.
> > >>
> > > Keep in mind that the appeal of vacuum-tube audio equipment is NOT
its
> > > "perfect" reproduction (which probably doesn't...in fact,
> > > CAN'T...exist?!) but rather the fact that the distortion it
generates
> > > is much more enjoyable for steady listening than its solid-state
> > > equivalent...?!
> >
> > Yes, but if you feed an unpleasantly distorted signal into a box
with a
> > tube in it, the tube will not magically remove that unpleasantness.
> >
> > Remarkable things can be done with software to improve a nasty
> > recording, and I expect such software to improve in the future, but
a
> > simple tube based amplifier stage cannot make a silk purse out of a
> > sow's ear.
> >
> That, actually, was my point...! If an audio signal has been, at any
> point in its life, been subjected to solid-state distortion...
> 
> 1) The listener has my deepest sympathy...
> 
> 2) AND...the signal will never again sound good, regardless of what
> it is played on/through...!
> 
> Steven C. Barr