"Bret Ludwig" wrote in message
oups.com...


Dynaco has been dead longer than Ronnie Reagan's penis and nothing
stops ST70 repair and refurbishment today.

Agreed, if you use a ST70 regularly, the repair and refurbishment will be
non-stop.

"Bill Evans" wrote in message
...

I still enjoy my H.H. Scott Stereomaster 384 stereo receiver at my summer
cottage. It is all discrete device ss amplifier stages and was rated at
about 75 Watts per channel in those days - likely about 20 Watts rms. It
still sounds great and works 100%.

My recollection is that H.H. Scott early SS gear pretty much met specs, but
I don't remember what they were for the 384.

What year?

"Barry Mann" wrote in message
om...

The L'il Tiger was a popular DIY project:
http://www.swtpc.com/mholley/Popular...PE_Dec1967.htm

Daniel Meyer was one of the early voices warning about trashy open loop
performance wrapped in tons of global feedback. Mostly he was ignored.

Good reason. DBTs comparing Meyer's relatively elaborate SS designs to more
conventional and simpler SS designs come up "no differences".

http://www.emersonscott.com/hhscotinchis.html

Indicates a Scott transistorized stereo receiver in 1964 and IC's in
use in 1966.

Yes, in the FM section.

One of the first ICs to make it big in stereo receivers was the CA3012 IF
amplifier/limiter IC.

John Stone wrote:
wrote:
John Stone wrote:

The IC 150 used (I believe) an LM301 in the high level portion and a
discrete circuit for the phono stage.

(Walt gets out his IC 150 service manual)

The ICs a

LF356H FET Op amp - master gain stage
LM301AN Op amp - gain stage for the phono preamp
MC78L18ACP - Voltage regulators


This sounds like a different preamp and one that is much later-perhaps an
IC150A?. I am certain that the original IC150 did not have this chip
complement, and that the only IC used was in the high level stage. The rest
was discrete.


Yes, you are right. I was talking about the IC 150A. The original IC
150 had a discreet phono section and a 301AN Op Amp for the main gain stage.

http://www.crownaudio.com/pdf/amps/ic150sm3.pdf

(hattip to Arne for the pointer to the legacy Crown manuals)

//Walt

Walt wrote:
John Stone wrote:

The IC 150 used (I believe) an LM301 in the high level portion and a
discrete circuit for the phono stage.

(Walt gets out his IC 150 service manual)

The ICs a

LF356H FET Op amp - master gain stage
LM301AN Op amp - gain stage for the phono preamp
MC78L18ACP - Voltage regulators

So, partial credit. (c:

The great thing about the IC 150 is that it was basically just a
switchbox with one gain stage. Minimal.

Hey Walt,

I'm about to 'attack' a DC-300A with a bum channel. Any hints? Do you
have a manual to download?

jak

jakdedert wrote:
Hey Walt,

I'm about to 'attack' a DC-300A with a bum channel. Any hints? Do you
have a manual to download?

http://www.crownaudio.com/gen_htm/legacy/legacamp.htm

Good luck.

//Walt

I bought the Scott 384 in late 1968. There were a lot of Sansui SS amps
also coming out at that time.

"Arny Krueger" wrote in message
. ..

"Bill Evans" wrote in message
...

My recollection is that H.H. Scott early SS gear pretty much met specs,
but I don't remember what they were for the 384.

What year?

Arny Krueger wrote:
"Bret Ludwig" wrote in message
oups.com...


Dynaco has been dead longer than Ronnie Reagan's penis and nothing
stops ST70 repair and refurbishment today.

Agreed, if you use a ST70 regularly, the repair and refurbishment will be
non-stop.

Actually Arny if youy knew what you are talking about you would know
that once you rebuuilt it once into a configuration that works it will
then run reliably thereafter with only hobbyist-friendly occasional
attention. Hobbyists don't mind.

Arny Krueger wrote:
"Barry Mann" wrote in message
om...

The L'il Tiger was a popular DIY project:
http://www.swtpc.com/mholley/Popular...PE_Dec1967.htm

Daniel Meyer was one of the early voices warning about trashy open loop
performance wrapped in tons of global feedback. Mostly he was ignored.

Good reason. DBTs comparing Meyer's relatively elaborate SS designs to more
conventional and simpler SS designs come up "no differences".

I remember a bass player friend who rebuilt a Tigersaurus according to
an article in TAA in the eighties and used it to replace a Peavey in
his bass rig. His preamp was the top section of an Ampeg SVT he ripped
out of one that had burned badly. When other local bass players heard
and played through his rig there was a big local run on Tigersauruses.

"Trevor Wilson" wrote in message
...
**Here is the original post:

Which is not the one I replid to. But it still says "audio amp IC's".

An op-amp *IS* an "audio amp IC". The driver stage *IS* part of the
power
amp.

**Part of, but not the entire power stage.

Where did anyone say it was?

MrT.

"Bret Ludwig" wrote in message
oups.com...
The Crowns were considered high magic by most hobbyists and unfixable
without factory support,

Most hobbyists still can't fix anything without factory support, so
what?

Dynaco has been dead longer than Ronnie Reagan's penis and nothing
stops ST70 repair and refurbishment today. And people misguidedly
recreate Western Electric amps fifty years after they were considered
well and truly useless. But they work like thay always did.

And your point is? Many people still fix Crown amps too. Probably why so
many are still operating just "like they always did".
But I agree some other old designs are easier to work on, and most modern
uprocessor controlled HT amps impossible even for some authorised service
centres!

MrT.

"Mr.T" MrT@home wrote in message
u...

"Trevor Wilson" wrote in message
...
**Here is the original post:

Which is not the one I replid to. But it still says "audio amp IC's".

**Indeed. It does NOT say: "audio PRE-amp ICs". Besides which, it is clear
that, based on the OP's words that he/she was asking about power ICs.


An op-amp *IS* an "audio amp IC". The driver stage *IS* part of the
power
amp.

**Part of, but not the entire power stage.

Where did anyone say it was?

**The existence of Voltage amplifier ICs, before 1970 is hardly news. The
existence of POWER amplifier ICs before 1970, most certainly would be.


--
Trevor Wilson
www.rageaudio.com.au

Walt wrote:
jakdedert wrote:
Hey Walt,

I'm about to 'attack' a DC-300A with a bum channel. Any hints? Do
you have a manual to download?

http://www.crownaudio.com/gen_htm/legacy/legacamp.htm

Good luck.

//Walt

Lovely...thanks. Would it that all manufacturers were this upfront with
service info.

jak

"Trevor Wilson" wrote in message
...
**Here is the original post:

Which is not the one I replid to. But it still says "audio amp IC's".

**Indeed. It does NOT say: "audio PRE-amp ICs".

Nor does it say "Audio POWER amp IC's" You do realise the term amplifier is
more general?
Time to stop flogging a dead horse, now we have both made it clear what we
were responding to.

MrT.

"jakdedert" wrote in message
.. .
Lovely...thanks. Would it that all manufacturers were this upfront with
service info.

Totally agree. Full service manuals were included in each box. How many
manufacturers were/are prepared to do that.

MrT.

"Mr.T" MrT@home wrote in message
u...

"jakdedert" wrote in message
.. .
Lovely...thanks. Would it that all manufacturers were this upfront with
service info.

Totally agree. Full service manuals were included in each box. How many
manufacturers were/are prepared to do that.

how many *need* to ?!!!

geoff

In article .com,
wrote:

JohnR66 wrote:
When did decent solid state power amps become available? Were they
direct, capacitor or transformer coupled to the load.

The Marantz 15 was introduced in 1968. The Marantz 16 was introduced
in 1969.

Back in the 60's when the first audio amp ICs became available for
battery powered radios and such, the engineers coupled the output
through a transformer! It seemed hard to wean them off the trans-
former. Finally in the 70s...

I know of no equipment from that era that used "audio amp IC's",
as the pretty much didn't exist at the time.

Sorry to disallusion you, but I was designing them into
professional-quality broadcast gear in about 1967-68.

Isaac

Trevor Wilson wrote:

**The existence of Voltage amplifier ICs, before 1970 is hardly news. The
existence of POWER amplifier ICs before 1970, most certainly would be.

You already know about Uncle Clive's IC-10 from 1968.

--
Eiron

"Geoff@home" wrote in message
...
Totally agree. Full service manuals were included in each box. How many
manufacturers were/are prepared to do that.

how many *need* to ?!!!

Good point, most aren't worth fixing.

MrT.

In article .com, "Bret Ludwig" wrote:

Arny Krueger wrote:
"Barry Mann" wrote in message
om...

The L'il Tiger was a popular DIY project:
http://www.swtpc.com/mholley/Popular...PE_Dec1967.htm

Daniel Meyer was one of the early voices warning about trashy open loop
performance wrapped in tons of global feedback. Mostly he was ignored.

Good reason. DBTs comparing Meyer's relatively elaborate SS designs to more
conventional and simpler SS designs come up "no differences".

I remember a bass player friend who rebuilt a Tigersaurus according to
an article in TAA in the eighties and used it to replace a Peavey in
his bass rig. His preamp was the top section of an Ampeg SVT he ripped
out of one that had burned badly. When other local bass players heard
and played through his rig there was a big local run on Tigersauruses.


I'm not sure if anything could touch the price. $300 for a pair.


greg

"Bret Ludwig" wrote in message
ups.com...

Arny Krueger wrote:
"Bret Ludwig" wrote in message
oups.com...


Dynaco has been dead longer than Ronnie Reagan's penis and nothing
stops ST70 repair and refurbishment today.

Agreed, if you use a ST70 regularly, the repair and refurbishment will be
non-stop.

Actually Arny if youy knew what you are talking about you would know
that once you rebuuilt it once into a configuration that works it will
then run reliably thereafter with only hobbyist-friendly occasional
attention.

Rebias it every week or once a month?

Retube every 6 months or every year?

Hobbyists don't mind.

Oh yes, the rituals are part of the fun for those who worship this way.

Me, I like to make and listen to music.

"GregS" wrote in message
...
In article .com, "Bret
Ludwig" wrote:

Arny Krueger wrote:
"Barry Mann" wrote in message
om...

The L'il Tiger was a popular DIY project:
http://www.swtpc.com/mholley/Popular...PE_Dec1967.htm

Daniel Meyer was one of the early voices warning about trashy open
loop
performance wrapped in tons of global feedback. Mostly he was ignored.

Good reason. DBTs comparing Meyer's relatively elaborate SS designs to
more
conventional and simpler SS designs come up "no differences".

I remember a bass player friend who rebuilt a Tigersaurus according to
an article in TAA in the eighties and used it to replace a Peavey in
his bass rig. His preamp was the top section of an Ampeg SVT he ripped
out of one that had burned badly. When other local bass players heard
and played through his rig there was a big local run on Tigersauruses.


I'm not sure if anything could touch the price. $300 for a pair.

To be more specific, I was talking about the Tiger .01. It was supposed to
*sound better* than the earlier Tigersaurus.

The Tigersauraus was a good price-performer and pretty robust as I recall.

It was something like a mono Ampzilla. BTW I seem to recall that Ampzilla
like Tigersauraus started out as Popular Electronics projects.

Geoff@home wrote:
"Mr.T" MrT@home wrote in message
u...
"jakdedert" wrote in message
.. .
Lovely...thanks. Would it that all manufacturers were this upfront with
service info.
Totally agree. Full service manuals were included in each box. How many
manufacturers were/are prepared to do that.

how many *need* to ?!!!

Meaning what...that contemporary gear doesn't break down? In what
universe are you living?

Perhaps you mean that when it 'does' break down, that it's cheaper to
sh*tcan and replace, than to find one of the dwindling number of
technicians who can actually fix things.....

jak

geoff

Mr.T wrote:
"jakdedert" wrote in message
.. .
Lovely...thanks. Would it that all manufacturers were this upfront with
service info.

Totally agree. Full service manuals were included in each box. How many
manufacturers were/are prepared to do that.

Well, there are service manuals, and then there are Service Manuals.
This is one of the latter...good reading even if one wasn't prepared to
dig into the device.

jak

MrT.

In article , jakdedert wrote:
Mr.T wrote:
"jakdedert" wrote in message
.. .
Lovely...thanks. Would it that all manufacturers were this upfront with
service info.

Totally agree. Full service manuals were included in each box. How many
manufacturers were/are prepared to do that.

Well, there are service manuals, and then there are Service Manuals.
This is one of the latter...good reading even if one wasn't prepared to
dig into the device.


All good companies should furnish easy access all their
schematics and manuals. By not furnishing documentation
the company gets two results. It saves money not furnishing paper.
The second thing it does, is frustrates many people, and
causes only delays in repair or even copying their equipment.
The first item can be ignored today with internet downloads.

greg

On Tue, 31 Jan 2006 23:11:17 -0800, Isaac Wingfield
wrote:

In article .com,
wrote:

JohnR66 wrote:
When did decent solid state power amps become available? Were they
direct, capacitor or transformer coupled to the load.

The Marantz 15 was introduced in 1968. The Marantz 16 was introduced
in 1969.

Back in the 60's when the first audio amp ICs became available for
battery powered radios and such, the engineers coupled the output
through a transformer! It seemed hard to wean them off the trans-
former. Finally in the 70s...

I know of no equipment from that era that used "audio amp IC's",
as the pretty much didn't exist at the time.

Sorry to disallusion you, but I was designing them into
professional-quality broadcast gear in about 1967-68.

*Power* ICs? I seriously doubt that - maybe you slipped a decade?
IIRC, the 709 was the latest and greatest audio IC around then, but
there were no integrated devices which would put out even one watt.
--

Stewart Pinkerton | Music is Art - Audio is Engineering

"Isaac Wingfield" wrote in message
...
In article .com,
wrote:

JohnR66 wrote:

Back in the 60's when the first audio amp ICs became available for
battery powered radios and such, the engineers coupled the output
through a transformer!

http://www.semiconductormuseum.com/T.../Lin_Page3.htm

Shows a drict-coupled ca. 1956 power amp designed by *the* Dr. Lin. The amp
shown has a transformer - for the power supply. BTW, note the selenium
rectifier stack.

It seemed hard to wean them off the trans- former. Finally in the
70s...

I know of no equipment from that era that used "audio amp IC's",
as the pretty much didn't exist at the time.

I seem to recall that in the 60s, the Lafayette store I worked at sold a
kind of an IC power amp. It was direct-coupled and composed of discrete
transistors encapsulated in a brick of epoxy.

Sorry to disallusion you, but I was designing them into
professional-quality broadcast gear in about 1967-68.

Those would no doubt be line-level circuits, right?

"jakdedert" wrote in message news:Fk4Ef.13707
how many *need* to ?!!!

Meaning what...that contemporary gear doesn't break down? In what
universe are you living?

I use a lot of gear in PA and studio environments, and I am a repair tech
fornearly 30 years. My experience it that gear is generally far far more
reliable now that before. Except VCRs which as at least as flakey as they
always were..

Perhaps you mean that when it 'does' break down, that it's cheaper to
sh*tcan and replace, than to find one of the dwindling number of
technicians who can actually fix things.....

That is true. Unfortunately in many ways. I alway fix my own stuff, but my
employer would not relish the loss of goodwill earned from fixing people's
gear at more than the cost of replacement with new.

Of course the economics change with the cost and nature of the equipment .

geoff

"Isaac Wingfield" wrote in message
...
In article .com,
wrote:

JohnR66 wrote:
When did decent solid state power amps become available? Were they
direct, capacitor or transformer coupled to the load.

The Marantz 15 was introduced in 1968. The Marantz 16 was introduced
in 1969.

Back in the 60's when the first audio amp ICs became available for
battery powered radios and such, the engineers coupled the output
through a transformer! It seemed hard to wean them off the trans-
former. Finally in the 70s...

I know of no equipment from that era that used "audio amp IC's",
as the pretty much didn't exist at the time.

Sorry to disallusion you, but I was designing them into
professional-quality broadcast gear in about 1967-68.

741s, 301s, or hybrids ?

geoff

"Arny Krueger" wrote in message
...


I seem to recall that in the 60s, the Lafayette store I worked at sold a
kind of an IC power amp. It was direct-coupled and composed of discrete
transistors encapsulated in a brick of epoxy.

And later came the Sanken...

geoff

Arny Krueger wrote:
"Bret Ludwig" wrote in message
ups.com...

Arny Krueger wrote:
"Bret Ludwig" wrote in message
oups.com...


Dynaco has been dead longer than Ronnie Reagan's penis and nothing
stops ST70 repair and refurbishment today.

Agreed, if you use a ST70 regularly, the repair and refurbishment will be
non-stop.

Actually Arny if youy knew what you are talking about you would know
that once you rebuuilt it once into a configuration that works it will
then run reliably thereafter with only hobbyist-friendly occasional
attention.

Rebias it every week or once a month?

Retube every 6 months or every year?

Hobbyists don't mind.

Oh yes, the rituals are part of the fun for those who worship this way.

Me, I like to make and listen to music.

Phooey. What recordings of yours can I buy at the local music store?

A properly reworked ST70 should need biasing once when retubed, once
after a few hours, and once again in 100 hrs or so. Yes, this is fun.
Output tubes are good for over a year if you turn the standing current
down somewhat-if you listen for several hours each day-and small signal
tubes several years often. For what it's worth i have a pair of VTLs
running hamfest 807s i haven't retubed in almost five years, it's
getting almost time-a ST70 shouldn't be much different. Soft start DC
filaments are a help. I'm sure. A separate filament xfmr would make
this easier and take a load off the overworked, underspecified power
transformer of course.

"Bret Ludwig" wrote in message
oups.com...

Arny Krueger wrote:
"Bret Ludwig" wrote in message
ups.com...

Arny Krueger wrote:
"Bret Ludwig" wrote in message
oups.com...


Dynaco has been dead longer than Ronnie Reagan's penis and nothing
stops ST70 repair and refurbishment today.

Agreed, if you use a ST70 regularly, the repair and refurbishment will
be
non-stop.

Actually Arny if youy knew what you are talking about you would know
that once you rebuuilt it once into a configuration that works it will
then run reliably thereafter with only hobbyist-friendly occasional
attention.

Rebias it every week or once a month?

Retube every 6 months or every year?

Hobbyists don't mind.

Oh yes, the rituals are part of the fun for those who worship this way.

Me, I like to make and listen to music.

Phooey. What recordings of yours can I buy at the local music store?

Irrelevant.

A properly reworked ST70 should need biasing once when retubed, once
after a few hours, and once again in 100 hrs or so. Yes, this is fun.

It detracts from listening to and making music.

Output tubes are good for over a year if you turn the standing current
down somewhat-if you listen for several hours each day-and small signal
tubes several years often.

So my 6 month retube schedule is pretty realistic.

For what it's worth i have a pair of VTLs
running hamfest 807s i haven't retubed in almost five years, it's
getting almost time-a ST70 shouldn't be much different.

Depends how much you listen to it.

Obviously, the best thing to do with tubed amps is to not listen to them
very often.

Soft start DC
filaments are a help. I'm sure. A separate filament xfmr would make
this easier and take a load off the overworked, underspecified power
transformer of course.

Hassle, hassle, hassle.

"Geoff@work" wrote in message
...

"Arny Krueger" wrote in message
...


I seem to recall that in the 60s, the Lafayette store I worked at sold a
kind of an IC power amp. It was direct-coupled and composed of discrete
transistors encapsulated in a brick of epoxy.

And later came the Sanken...

Those are hybrid chips, right?

IOW a chunk of ceramic or other insulator with parts attached and then
encapsulated.

Late 1960s - early 70s.

On Thu, 2 Feb 2006 09:28:03 -0500, "Arny Krueger"
wrote:


"Geoff@work" wrote in message
.. .

"Arny Krueger" wrote in message
...


I seem to recall that in the 60s, the Lafayette store I worked at sold a
kind of an IC power amp. It was direct-coupled and composed of discrete
transistors encapsulated in a brick of epoxy.

And later came the Sanken...

Those are hybrid chips, right?

IOW a chunk of ceramic or other insulator with parts attached and then
encapsulated.

Late 1960s - early 70s.

Yes, that technology persisted well into the '80s for power devices,
even into the '90s for military gear. Arguably not a true integrated
circuit, since several discrete chips were involved.
--

Stewart Pinkerton | Music is Art - Audio is Engineering

Arny Krueger wrote:

A properly reworked ST70 should need biasing once when retubed, once
after a few hours, and once again in 100 hrs or so. Yes, this is fun.

It detracts from listening to and making music.

Output tubes are good for over a year if you turn the standing current
down somewhat-if you listen for several hours each day-and small signal
tubes several years often.

So my 6 month retube schedule is pretty realistic.

A year was 12 months, the last time I checked. But for most listeners
three or four is adequate, particularly if soft start is fitted and
they turn it off when not listening. My sapphic spinster aunt's Zenith
console worked with no retubes in almost 35 years. I'm reworking it for
her now. The 6V6s I pulled out of it are now in a guitar amp-they are
50+ year old original Zenith tubes as was the 80 rectifier I smashed
because it was intermittent.(I saved the base.) I'm taking the power
section out and converting it to a stereo line source for use with
external speakers.

For what it's worth i have a pair of VTLs
running hamfest 807s i haven't retubed in almost five years, it's
getting almost time-a ST70 shouldn't be much different.

Depends how much you listen to it.

Obviously, the best thing to do with tubed amps is to not listen to them
very often.

Only if you don't care for the superior sound quality.

Soft start DC
filaments are a help. I'm sure. A separate filament xfmr would make
this easier and take a load off the overworked, underspecified power
transformer of course.

Hassle, hassle, hassle.

Go to Best Buy, you consumer.

"Bret Ludwig" wrote in message
ups.com...
Obviously, the best thing to do with tubed amps is to not listen to them
very often.

Only if you don't care for the superior sound quality.

Yes, many people prefer the accuracy of solid state sound to the "superior
sound quality" of tubes.
(The idea that they may in fact be inferior is a concept too awful to
contemplate if it shatters your self delusion)

MrT.

In article ,
"Geoff@work" wrote:

"Isaac Wingfield" wrote in message
...
In article .com,
wrote:

JohnR66 wrote:
When did decent solid state power amps become available? Were they
direct, capacitor or transformer coupled to the load.

The Marantz 15 was introduced in 1968. The Marantz 16 was introduced
in 1969.

Back in the 60's when the first audio amp ICs became available for
battery powered radios and such, the engineers coupled the output
through a transformer! It seemed hard to wean them off the trans-
former. Finally in the 70s...

I know of no equipment from that era that used "audio amp IC's",
as the pretty much didn't exist at the time.

Sorry to disallusion you, but I was designing them into
professional-quality broadcast gear in about 1967-68.

741s, 301s, or hybrids ?

741's for low gain applications where their limited slew rate wasn't a
problem; for a headphone amp, say.

There was a faster "audio specific" Fairchild part, too -- (mu)A739,
perhaps? I used one of those for voltage gain in a very low
crossover-distortion 30 watt amp. I had some high-efficiency horn-loaded
speakers, and the amp spent most of it's time delivering well under 50
milliwatts; crossover distortion is a real problem in that region. In
other words, at low output powers, it comprises a larger percentage of
the total output. There's a very good reason why early solid-state amps
always had their distortion measured at the highest possible power.

Then or shortly after, LM318's showed up, and they were quite nice for
everything except the most critical low-noise applications.

Isaac

In article ,
Stewart Pinkerton wrote:

On Tue, 31 Jan 2006 23:11:17 -0800, Isaac Wingfield
wrote:

In article .com,
wrote:

JohnR66 wrote:
When did decent solid state power amps become available? Were they
direct, capacitor or transformer coupled to the load.

The Marantz 15 was introduced in 1968. The Marantz 16 was introduced
in 1969.

Back in the 60's when the first audio amp ICs became available for
battery powered radios and such, the engineers coupled the output
through a transformer! It seemed hard to wean them off the trans-
former. Finally in the 70s...

I know of no equipment from that era that used "audio amp IC's",
as the pretty much didn't exist at the time.

Sorry to disallusion you, but I was designing them into
professional-quality broadcast gear in about 1967-68.

*Power* ICs? I seriously doubt that - maybe you slipped a decade?
IIRC, the 709 was the latest and greatest audio IC around then, but
there were no integrated devices which would put out even one watt.

Using them for the voltage gain stage in power amplifiers. Perhaps that
doesn't count.

Isaac

"Bret Ludwig" wrote in message
ups.com...

Arny Krueger wrote:

Obviously, the best thing to do with tubed amps is to not listen to them
very often.

Only if you don't care for the superior sound quality.

Does such a thing even exist as perceived by an unbiased listener?


Go to Best Buy, you consumer.

If I did a straight-wire bypass test comparing a ST-70 to the amp section of
a Best Buy $79.95 100 wpc stereo receiver, with my standard speaker load,
which amp's outputs would most resemble the input?

Arny Krueger wrote:
"Bret Ludwig" wrote in message
ups.com...

Arny Krueger wrote:

Obviously, the best thing to do with tubed amps is to not listen to them
very often.

Only if you don't care for the superior sound quality.

Does such a thing even exist as perceived by an unbiased listener?


Go to Best Buy, you consumer.

If I did a straight-wire bypass test comparing a ST-70 to the amp section of
a Best Buy $79.95 100 wpc stereo receiver, with my standard speaker load,
which amp's outputs would most resemble the input?

A stock ST70? Probably the Best Buy receiver. But let's run the test
in 2046 just to be sure.