Re: Hifi landmarks

Arny,
Just a few notes in respond to your kind comments.
1. The Victrola is utterly seminal, which is why it's on the list.
2. Please nominate a WE amplifier. I agree with you that one should be
included.
3. You're right! Replace St-70 with an Acrosound.
4. The Dyna Stereo 80 is a simplification of the Stereo 120. That is why I
chose the 120..
5. Your comment about the RCA SS design is informative. However, in this
list, I would like to, as much as possible, choose representative physical
units, rather than schematics.
6. Neither the early DC-300 nor the DC-300A were bulletproof. I included
them as one item because of distortion figures remarkable for the time,
achieved by precision biasing. A lot of people don't like the way they
sound. This, too, is noteworthy.
7. If, in fact, Hitachi actually sold a MOSFET amplifier, rather than
samples and OEM modules, please supply one of the model designations, and I
will make the replacement.
8. If I recall correctly, the Krell had a completely regulated supply. It
may have also employed more use of active current sources than other
amplifiers of the time. On the other hand, it could be representative of
nothing. I await input from more people on this.
9. Modern SET: I am no fan of tubes. I have never enjoyed SET. I wandered
the NY Hifi show looking for good sounding SET, and found none. It appears
on this list not because of a personal preference or bias, but because it is
a trend all in itself.
10. Yes, there are a number of switching designs. I have chosen not to make
this list overly complex. It would be impossible to recognize every
technical innovation in amplifier design in a compact list. Such a list
would then be a chronology, rather than a list of benchmarks.

Your assertion that modern amplifiers are overhyped may be true. I do not
own a "modern" amplifier. I have lugged what I have at intervals over to a
buddy's place, and compared what I have to so-called modern amplifiers, and
never been disappointed in what I have. Whether advancement in the past ten
years has been overrated must be the subject of another thread. In
determining what belongs on a list of landmarks, the human factor is
important. This is a "history" of interaction of people with technology, not
either by itself.


"Arny Krueger" <arnyk@xxxxxxxxxx> wrote in message
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"soundhaspriority" <nowhere@xxxxxxxxxxx> wrote in message
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1. The RCA Victrola

No amplifier.

<note ignorance of Western Electric power amps>

2. Williamson amplifiers

OK

3. The Ultralinear design, which may be sampled as the
Dynaco Stereo 70

By most accounts the Acrosound power amp was at or near the apex of this
line.

4. Pick one tube Macintosh.

Relevant technology - the cathode-coupled output transformer with gobs of
local feedback.

4. The Dyna Stereo 120, as perhaps the end evolution of
capacitively coupled bipolar amplifiers.

Error! Corrected elsewhere.

Note ignorance of the first generation of SS amps with germanium output
transistors.

Note ignorance of the generation of SS amps with driver transformers.

Note ignorance of the generation of quasi-complementary power amplifiers

5. 1st generation direct coupled amps. Many were made.

Most were close clones of a design published in the RCA transistor manual.

6. Clean bipolar solid state.

Many of the designs already listed fit the bill.

Several approaches
resulted in pretty good results: Crown DC300/DC300A,

Note ignorance of the generation of high-powered SS amps with inadequate
current/voltage capabilites, of which the early DC300 was just one
example.

MacIntosh, etc. Both used precision biasing to reduce
measured distortion far below what was previously achieved.

Just didn't happen.

7. The MOSFET amp. The Hafler DH-200, and the Acoustat
TNT-200, both early 1980's.

Ignores that Hitachi first innovated the use of their FET devices in
their own branded equipment.

8. Pick a Krell or other "blameless" design, representing
bipolar amplifiers of a very high standard.

Not clear at all that Krell innovated much of anything outside of gross
weight, overbuilding, and marketing hype. Clearest form of Krell marketing
hype was their innovation of vastly derating their amps power ratings at 8
ohms in order to make it appear that their amps approached the idea of
providing twice the power at half the impedance.

9. A modern SET amplifier.

Oxymoron. Their are no modern SETs - they are all throwbacks to a
generation of power amps that never really existed. Push-pull was
invented early enogh and advantageous enough that almost no class-A single
ended power amps were ever built in the days of tubes.

10. A modern switching amplifier.

Note lack of distinction of power amps that have switchmode signal
handling, and those that have switchmode power supplies. All 4 possible
permutations exist on the market.

Each of these products was followed by a host of
competitors with equal, better, or simply different
quality, or a mutation with different sonic
characteristics.

The categories and examples chosen by the OP are obviously based on
ignorance of history, the evolution of technology, and current technology.
Consider the source.



.

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