More about that Chinese amp

[Fox's Mercantile]

On 1/1/20 3:33 PM, Trevor Wilson wrote:

**Good for you. Call a spade a spade and stop encouraging people to
persevere with cheap, shitty, Chinese tube amps. In fact, there is no
sane reason to use ANY tube amp in a quality hi fi system.

Ya know, not everyone gives a rat's ass about having a "quality hi fi
system."

There are those of us that might be able to tell the difference, but
choose our "cheap piece of shit" system to listen to instead. Solid
State or tube.

Because to us, at the end of the day, it's just something to listen
to, not have some religious experience.

--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Trevor Wilson]

On 2/01/2020 8:45 am, Fox's Mercantile wrote:

On 1/1/20 3:33 PM, Trevor Wilson wrote:
**Good for you. Call a spade a spade and stop encouraging people to
persevere with cheap, shitty, Chinese tube amps. In fact, there is no
sane reason to use ANY tube amp in a quality hi fi system.

Ya know, not everyone gives a rat's ass about having a "quality hi fi
system."

**Have you been reading the thread? The original poster is trying to
repair a cheap, shitty, Chinese tube amp. There is no case that can be
presented to suggest that such an amplifier makes any kind of sense in a
system. ANY system. A cheap SS amp will cost less and provide superior
performance and reliability. Such an amp may not provide the same pride
of ownership though.

There are those of us that might be able to tell the difference, but
choose our "cheap piece of shit" system to listen to instead. Solid
State or tube.

**Sure. I use such a system for my TV listening. However, just a single,
decent quality, output transformer for a tube amp can easily cost more
than an entire, decent quality SS amp.

Because to us, at the end of the day, it's just something to listen
to, not have some religious experience.

**Again: Read the thread.


--
Trevor Wilson
www.rageaudio.com.au

 

[Bob Engelhardt]

On 1/1/2020 4:23 PM, Trevor Wilson wrote:
....

I have no time for bullshit, like cheap, shitty, Chinese tube amps.
...

You seem to be spending time here ranting about them. What's it to you
if Eric chooses the amp he has. He's not asking for amp selection
advice. Quite the contrary. Let it go.

 

[Trevor Wilson]

On 2/01/2020 10:21 am, Bob Engelhardt wrote:

On 1/1/2020 4:23 PM, Trevor Wilson wrote:
...
I have no time for bullshit, like cheap, shitty, Chinese tube amps.
...

You seem to be spending time here ranting about them.  What's it to you
if Eric chooses the amp he has. He's not asking for amp selection
advice.  Quite the contrary.  Let it go.

**I care for several reasons:

* When people support dodgy manufacturers, it encourages those
manufacturers to foist yet more shitty products to market.
* When people refuse to accept that they made a mistake by buying a
cheap, shitty amplifier, they may encourage others to purchase similar
products. This sets a poor precedent, as there are many quite decent SS
amplifiers available, for quite decent prices.
* I have considerable experience with cheap, shitty amplifiers (not just
tube ones). I fix 'em for a living. Owners can waste stupid amounts of
money trying to deal with poor manufacturing techniques and/or outright
stupid design. I am attempting to save the original poster considerable
angst.

[Anecdote] One of my mates learned to drive on a 1934 Ford V8. He has
many fond memories of the car. He is a wealthy guy and recently spent a
small fortune (>AUS$100k) buying and fully restoring a nice example of
that car. After one, 100km trip in the car, he sold it. At a substantial
loss. It caused him a great deal of trouble and driving it was not what
he remembered.

We can all remember our first (few) amps. Mine were all tube ones (all
built by me). I loved them a lot. I can also remember the considerable
cost involved in replacing the tubes in a couple of them. KT88 tubes
were expensive back then. Now, original GE MOV KT88 tubes insanely
expensive. Chinese substitutes are shit.

Time to move on. Tubes are so 1950s. Great back then. Not so much now.

--
Trevor Wilson
www.rageaudio.com.au

 

On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:

On 1/01/2020 4:20 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 9:34 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 5:50 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 4:45 am, etpm@whidbey.com wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, shitty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my shitty tube amp and grouse about it while we grouse about
our shitty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.

Someone's never had a good tube amp.

 

[pfjw@aol.com]

They are on your website. You and no one but you is 100% responsible for the contents of your website.

Repeat:

Hypocrite.
Liar.
Pompous jackass.
Complete asshole.

Peter Wieck
Melrose Park, PA

 

[Trevor Wilson]

On 2/01/2020 12:07 pm, tabbypurr@gmail.com wrote:

On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 9:34 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 5:50 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 4:45 am, etpm@whidbey.com wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, shitty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my shitty tube amp and grouse about it while we grouse about
our shitty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.

Someone's never had a good tube amp.

**Now you're just being silly. I've had the opportunity to listen to a
VERY wide range of amplifiers in my systems (numbering in the hundreds).
More than most, as my job is fixing them. I listen to all of them as
part of my test procedure. I've been servicing tube amps for more than
50 (gulp) years. I've built few too. In fact, I can tell you that a
REALLY good tube amp, when driving suitably benign impedance speakers,
will sound almost indistinguishable from a good SS amp. In fact, I was
fooled once. I thought I was listening to a Krell, when I was listening
to a rather good Audio Research. Here's the thing:

Really good tube amps sound just like really good (or even not so good)
SS amps. I can state that from personal experience.

Cheap, shitty tube amps sound very different from really good tube amps
(and most SS amps). They sound different because they introduce various
forms of distortion.

Look at the frequency response curve, when operating into a typical
speaker load (black curve), of a shitty tube amp:

https://www.stereophile.com/content/audio-note-jinro-integrated-amplifier-measurements

I chose that amp, because it was easy to find on the Stereophile site.
There are many more examples.

Here is the response of another shitty tube amp, with audible flaws):

https://www.stereophile.com/content/audio-research-vsi60-integrated-amplifier-measurements

Here is the response of an amp that I felt was acceptable in my system
(still far from perfect):

https://www.stereophile.com/content/audio-research-reference-110-power-amplifier-measurements


Here is the response of a cheap SS amp, which I felt sounded as good as
ANY tube amp (power output limitations excepted):

https://www.stereophile.com/content/marantz-pm5003-integrated-amplifier-measurements

Far from perfect, but not too horrible.

You'll note the audibly significant frequency response variations
inherent to most tube amps. This form of linear distortion is VERY
audible. And not acceptable to me. This and other distortions do not
exist in most competently designed SS amps.



--
Trevor Wilson
www.rageaudio.com.au

 

[Trevor Wilson]

On 2/01/2020 12:22 pm, pfjw@aol.com wrote:

They are on your website. You and no one but you is 100% responsible for the contents of your website.

Repeat:

Hypocrite.
Liar.
Pompous jackass.
Complete asshole.

Peter Wieck
Melrose Park, PA

**Fuck off dickhead.

You can defend cheap, shitty tube amps all you like. You know that
you're wrong, so you grasp at straws.

--
Trevor Wilson
www.rageaudio.com.au

 

[Chuck]

On Wed, 1 Jan 2020 17:07:43 -0800 (PST), tabbypurr@gmail.com wrote:

On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 9:34 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 5:50 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 4:45 am, etpm@whidbey.com wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, shitty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my shitty tube amp and grouse about it while we grouse about
our shitty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.

Someone's never had a good tube amp.

One tube amp that I'm fond of is the McIntosh 275s. Rebuilt a pair of
them in the mid 80s and listened to them extensively before selling
them. They were the best sounding tube amps I've ever heard.

 

[pfjw@aol.com]

Oh, good LORD, you are even more stupid than I thought.

I am not "defending" Chinese Junque at any level or in any way, shape or form. I am defending Eric's right to choose such equipment without criticism from you or anyone else. You share the same character flaw as your fellow wanker Phil Allison: When caught in a lie (or error of any sort), all you can do is lash out.

Peter Wieck
Melrose Park, PA

 

[Trevor Wilson]

On 3/01/2020 1:21 am, pfjw@aol.com wrote:

Oh, good LORD, you are even more stupid than I thought.

I am not "defending" Chinese Junque at any level or in any way, shape or form. I am defending Eric's right to choose such equipment without criticism from you or anyone else. You share the same character flaw as your fellow wanker Phil Allison: When caught in a lie (or error of any sort), all you can do is lash out.

**Here are YOUR words:

"Making you both a hypocrite and a liar."

"Hypocrite."
"Liar."
"Pompous jackass."
"Complete asshole."

Let us discuss my alleged "lashing out".

YOU are the one resorting to name calling. Not me. I have consistently
stated facts. Nothing more.

Eric certainly has every right to choose any junk he wants to own and
use. Just as I have every right (nay, duty) to explain what a
monumentally daft idea it is to use cheap, shitty tube equipment in any
system. I do so on a regular basis, when presented with such junk for
service. The same goes for cheap (and sometimes not cheap), shitty SS
equipment. I call a spade a spade. Shitty equipment should be jettisoned
and the owner can get on with life, rather than attempting to enjoy
something that will merely cause frustration.

You should also note that I very carefully showed why tubes, in general
and cheap, shitty tube amps, specifically, are a stupid idea for a high
fidelity audio reproduction system in 2019. I did so, using published
graphs and an assumption that the readers of this group have the
technical abilities to understand those graphs and their implications
for real-world loudspeakers.

That is hardly "lashing out". Any suggestion that I have a resemblance
to one of my country-men is insulting. And wrong.

I note that you focus on ONE ad for cables on my site. Those cables were
placed there as a consignment sale for a client of some 30 years
standing. He ended up in the clutches of another dealer, who extolled
the virtues of the cables. I advised him, in no uncertain terms, that
the money would be better spent on room treatments, new speakers, or
some jewellery for his wife. He ignored me. After he realised the error
of his ways, he asked me to sell the cables for him. I agreed to do so
(reluctantly), due to our long relationship. He gave up waiting for me
to sell the cables and took them back. We have not spoken since. That
was more than a year ago. And yes, I should have removed the ad. I'll
get around to it.


--
Trevor Wilson
www.rageaudio.com.au

 

[Fox's Mercantile]

Give it a fucking rest sport.
You'd do well to just shut the fuck up now instead repeatedly
going on about how somebody's piece of kit is a piece of shit.

It's as simple as that.

The problem with Eric's "Chinese piece of shit" was a defective
EL34 tube.


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Ed Vance]

01-03-20 06:46 Trevor Wilson wrote to pfjw@aol.com about Re: More about that
Chine
Howdy Trevor,

TW> @MSGID: <5E0E846B.4451.elerepar@capitolcityonline.net>
TW> @REPLY: <5E0E1412.4444.elerepar@capitolcityonline.net>
TW> On 3/01/2020 1:21 am, pfjw@aol.com wrote:
-Snip-
TW> You should also note that I very carefully showed why tubes, in general
TW> and cheap, .... tube amps, specifically, are a stupid idea for a high
TW> fidelity audio reproduction system in 2019. I did so, using published
TW> graphs and an assumption that the readers of this group have the
TW> technical abilities to understand those graphs and their implications
TW> for real-world loudspeakers.

The BBS I use added this Conference last Year (2019).
I have looked at a few messages, but thought to post my first message here
about the Tube Amplifier topic.

When I was in High School (1956-1959) I told a friend that I wondered
if a Intercom systems Audio Output on one end could be ran through a Diode
positioned on one lead -->|--

and the Audio Output at the other end have a Diode positioned --|<-- to
have a Two Way conversation without either end having to flip the
Listen - Talk Switch, and no Audio Feedback could occur because of the
difference of Polarity.

My friend connected a Diode between an Audio Amplifier and a Speaker and
I remember the sound I heard was terrible, distorted iirc.

I built a Heathkit AA-32 Tubed Stereo Amplifier in the 1970's.
I can't remember if Heath offered Transitorized Stereo Amplifiers back then.

I've heard beautiful Audio from Both Transistorized and Tubed Hi-Fi System.
BUT
I always remember hearing the racket coming out of my friends speaker when
he used that Diode to demostrate what it would sound like.
AND
When I (even) see a advertisement for a Semiconductor Audio Amp I always
think why did a Square Wave sound so bad back then but doesn't in the gear
sold now.

73 de Ed W9ODR . .


.... Have you checked your smoke detector batteries & Fire Ext, LATELY?!

 

[John-Del]

On Friday, January 3, 2020 at 7:15:21 PM UTC-5, Ed Vance wrote:

01-03-20 06:46 Trevor Wilson wrote to pfjw@aol.com about Re: More about that
Chine
Howdy Trevor,

TW> @MSGID: <5E0E846B.4451.elerepar@capitolcityonline.net
TW> @REPLY: <5E0E1412.4444.elerepar@capitolcityonline.net
TW> On 3/01/2020 1:21 am, pfjw@aol.com wrote:
-Snip-
TW> You should also note that I very carefully showed why tubes, in general
TW> and cheap, .... tube amps, specifically, are a stupid idea for a high
TW> fidelity audio reproduction system in 2019. I did so, using published
TW> graphs and an assumption that the readers of this group have the
TW> technical abilities to understand those graphs and their implications
TW> for real-world loudspeakers.

The BBS I use added this Conference last Year (2019).
I have looked at a few messages, but thought to post my first message here
about the Tube Amplifier topic.

When I was in High School (1956-1959) I told a friend that I wondered
if a Intercom systems Audio Output on one end could be ran through a Diode
positioned on one lead -->|--

and the Audio Output at the other end have a Diode positioned --|<-- to
have a Two Way conversation without either end having to flip the
Listen - Talk Switch, and no Audio Feedback could occur because of the
difference of Polarity.

My friend connected a Diode between an Audio Amplifier and a Speaker and
I remember the sound I heard was terrible, distorted iirc.

I built a Heathkit AA-32 Tubed Stereo Amplifier in the 1970's.
I can't remember if Heath offered Transitorized Stereo Amplifiers back then.

I've heard beautiful Audio from Both Transistorized and Tubed Hi-Fi System.
BUT
I always remember hearing the racket coming out of my friends speaker when
he used that Diode to demostrate what it would sound like.
AND
When I (even) see a advertisement for a Semiconductor Audio Amp I always
think why did a Square Wave sound so bad back then but doesn't in the gear
sold now.

73 de Ed W9ODR . .


... Have you checked your smoke detector batteries & Fire Ext, LATELY?!

Not sure of your point but if you used a diode of any construction including a vaccuum tube diode, you would have heard the same distortion.

 

[Jeff Urban]

You'd do well to just shut the fuck up now instead repeatedly
going on about how somebody's piece of kit is a piece of shit.

Pretty early in the year for me to agree with you but I do. This is sci.electronics.repair, not how.to.go.to.bestbuy.and.give.MORE.money.to.the.chinese.

 

On Thursday, 2 January 2020 01:33:30 UTC, Trevor Wilson wrote:

On 2/01/2020 12:07 pm, tabbypurr wrote:
On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 9:34 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 5:50 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 4:45 am, etpm@whidbey.com wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, shitty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my shitty tube amp and grouse about it while we grouse about
our shitty "leaders". I'm sure the amp will sound better than Trump..
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.

Someone's never had a good tube amp.


**Now you're just being silly. I've had the opportunity to listen to a
VERY wide range of amplifiers in my systems (numbering in the hundreds).
More than most, as my job is fixing them. I listen to all of them as
part of my test procedure. I've been servicing tube amps for more than
50 (gulp) years. I've built few too. In fact, I can tell you that a
REALLY good tube amp, when driving suitably benign impedance speakers,
will sound almost indistinguishable from a good SS amp. In fact, I was
fooled once. I thought I was listening to a Krell, when I was listening
to a rather good Audio Research. Here's the thing:

Really good tube amps sound just like really good (or even not so good)
SS amps. I can state that from personal experience.

Cheap, shitty tube amps sound very different from really good tube amps
(and most SS amps). They sound different because they introduce various
forms of distortion.

Look at the frequency response curve, when operating into a typical
speaker load (black curve), of a shitty tube amp:

https://www.stereophile.com/content/audio-note-jinro-integrated-amplifier-measurements

I chose that amp, because it was easy to find on the Stereophile site.
There are many more examples.

Here is the response of another shitty tube amp, with audible flaws):

https://www.stereophile.com/content/audio-research-vsi60-integrated-amplifier-measurements

Here is the response of an amp that I felt was acceptable in my system
(still far from perfect):

https://www.stereophile.com/content/audio-research-reference-110-power-amplifier-measurements


Here is the response of a cheap SS amp, which I felt sounded as good as
ANY tube amp (power output limitations excepted):

https://www.stereophile.com/content/marantz-pm5003-integrated-amplifier-measurements

Far from perfect, but not too horrible.

You'll note the audibly significant frequency response variations
inherent to most tube amps. This form of linear distortion is VERY
audible. And not acceptable to me. This and other distortions do not
exist in most competently designed SS amps.

I've also built a few tube amps and listened to a fair number of valve & tranny amps, though not 100s. Sure their foibles are different, with neither being perfect. My experience fwiw is I've never found any tranny amp that has the sound quality of a Quad II or a Sansui 500A. I used to be more involved in audio, not much now.


NT

 

[Fox's Mercantile]

On 1/4/20 9:13 PM, tabbypurr@gmail.com wrote:
> I used to be more involved in audio, not much now.

And apparently incapable of using an editor.

--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Trevor Wilson]

On 5/01/2020 2:13 pm, tabbypurr@gmail.com wrote:

On Thursday, 2 January 2020 01:33:30 UTC, Trevor Wilson wrote:
On 2/01/2020 12:07 pm, tabbypurr wrote:
On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 9:34 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 5:50 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 4:45 am, etpm@whidbey.com wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, shitty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my shitty tube amp and grouse about it while we grouse about
our shitty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.

Someone's never had a good tube amp.


**Now you're just being silly. I've had the opportunity to listen to a
VERY wide range of amplifiers in my systems (numbering in the hundreds).
More than most, as my job is fixing them. I listen to all of them as
part of my test procedure. I've been servicing tube amps for more than
50 (gulp) years. I've built few too. In fact, I can tell you that a
REALLY good tube amp, when driving suitably benign impedance speakers,
will sound almost indistinguishable from a good SS amp. In fact, I was
fooled once. I thought I was listening to a Krell, when I was listening
to a rather good Audio Research. Here's the thing:

Really good tube amps sound just like really good (or even not so good)
SS amps. I can state that from personal experience.

Cheap, shitty tube amps sound very different from really good tube amps
(and most SS amps). They sound different because they introduce various
forms of distortion.

Look at the frequency response curve, when operating into a typical
speaker load (black curve), of a shitty tube amp:

https://www.stereophile.com/content/audio-note-jinro-integrated-amplifier-measurements

I chose that amp, because it was easy to find on the Stereophile site.
There are many more examples.

Here is the response of another shitty tube amp, with audible flaws):

https://www.stereophile.com/content/audio-research-vsi60-integrated-amplifier-measurements

Here is the response of an amp that I felt was acceptable in my system
(still far from perfect):

https://www.stereophile.com/content/audio-research-reference-110-power-amplifier-measurements


Here is the response of a cheap SS amp, which I felt sounded as good as
ANY tube amp (power output limitations excepted):

https://www.stereophile.com/content/marantz-pm5003-integrated-amplifier-measurements

Far from perfect, but not too horrible.

You'll note the audibly significant frequency response variations
inherent to most tube amps. This form of linear distortion is VERY
audible. And not acceptable to me. This and other distortions do not
exist in most competently designed SS amps.

I've also built a few tube amps and listened to a fair number of valve & tranny amps, though not 100s. Sure their foibles are different, with neither being perfect. My experience fwiw is I've never found any tranny amp that has the sound quality of a Quad II or a Sansui 500A. I used to be more involved in audio, not much now.

**I Would sincerely hope that no reputable amplifier manufacturer (tube
or SS) would try to build an amp that sounds as bad as either. Both have
serious measurable and audible flaws.


--
Trevor Wilson
www.rageaudio.com.au

 

[Ed Vance]

01-04-20 02:35 John-Del wrote to Ed Vance about Re: More about that Chine
Howdy! John-Del,
-snip-

When I was in High School (1956-1959) I told a friend that I wondered
if a Intercom systems Audio Output on one end could be ran through a Diode
positioned on one lead -->|--

and the Audio Output at the other end have a Diode positioned --|<-- to
have a Two Way conversation without either end having to flip the
Listen - Talk Switch, and no Audio Feedback could occur because of the
difference of Polarity.

My friend connected a Diode between an Audio Amplifier and a Speaker and
I remember the sound I heard was terrible, distorted iirc.

I built a Heathkit AA-32 Tubed Stereo Amplifier in the 1970's.
I can't remember if Heath offered Transitorized Stereo Amplifiers back then.

I've heard beautiful Audio from Both Transistorized and Tubed Hi-Fi System.
BUT
I always remember hearing the racket coming out of my friends speaker when
he used that Diode to demostrate what it would sound like.
AND
When I (even) see a advertisement for a Semiconductor Audio Amp I always
think why did a Square Wave sound so bad back then but doesn't in the gear
sold now.

Jo> Not sure of your point but if you used a diode of any construction
Jo> including a vaccuum tube diode, you would have heard the same
Jo> distortion.

I have always thought a Audio Sinewave going through a Transistor would
come out as a Squarewave, not a Sinewave.

To my way of thinking a Sinewave is Pure Audio, a Squarewave would make
the signal sound distorted (a bit?).

Does it happen as I imagine, or am I way off base.

I never seen the pattern of the output on an oscilloscope so I don't really
know.

73 de Ed W9ODR

.... There is always one more thing for Me to learn...

 

[Chuck]

On Sun, 5 Jan 2020 15:37:08 +1100, Trevor Wilson
<trevor@rageaudio.com.au> wrote:

On 5/01/2020 2:13 pm, tabbypurr@gmail.com wrote:
On Thursday, 2 January 2020 01:33:30 UTC, Trevor Wilson wrote:
On 2/01/2020 12:07 pm, tabbypurr wrote:
On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 9:34 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 5:50 am, etpm@whidbey.com wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
trevor@rageaudio.com.au> wrote:

On 31/12/2019 4:45 am, etpm@whidbey.com wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, shitty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my shitty tube amp and grouse about it while we grouse about
our shitty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.

Someone's never had a good tube amp.


**Now you're just being silly. I've had the opportunity to listen to a
VERY wide range of amplifiers in my systems (numbering in the hundreds).
More than most, as my job is fixing them. I listen to all of them as
part of my test procedure. I've been servicing tube amps for more than
50 (gulp) years. I've built few too. In fact, I can tell you that a
REALLY good tube amp, when driving suitably benign impedance speakers,
will sound almost indistinguishable from a good SS amp. In fact, I was
fooled once. I thought I was listening to a Krell, when I was listening
to a rather good Audio Research. Here's the thing:

Really good tube amps sound just like really good (or even not so good)
SS amps. I can state that from personal experience.

Cheap, shitty tube amps sound very different from really good tube amps
(and most SS amps). They sound different because they introduce various
forms of distortion.

Look at the frequency response curve, when operating into a typical
speaker load (black curve), of a shitty tube amp:

https://www.stereophile.com/content/audio-note-jinro-integrated-amplifier-measurements

I chose that amp, because it was easy to find on the Stereophile site.
There are many more examples.

Here is the response of another shitty tube amp, with audible flaws):

https://www.stereophile.com/content/audio-research-vsi60-integrated-amplifier-measurements

Here is the response of an amp that I felt was acceptable in my system
(still far from perfect):

https://www.stereophile.com/content/audio-research-reference-110-power-amplifier-measurements


Here is the response of a cheap SS amp, which I felt sounded as good as
ANY tube amp (power output limitations excepted):

https://www.stereophile.com/content/marantz-pm5003-integrated-amplifier-measurements

Far from perfect, but not too horrible.

You'll note the audibly significant frequency response variations
inherent to most tube amps. This form of linear distortion is VERY
audible. And not acceptable to me. This and other distortions do not
exist in most competently designed SS amps.

I've also built a few tube amps and listened to a fair number of valve & tranny amps, though not 100s. Sure their foibles are different, with neither being perfect. My experience fwiw is I've never found any tranny amp that has the sound quality of a Quad II or a Sansui 500A. I used to be more involved in audio, not much now.


**I Would sincerely hope that no reputable amplifier manufacturer (tube
or SS) would try to build an amp that sounds as bad as either. Both have
serious measurable and audible flaws.

The 500A also had heat related drifting cap values in the MPX circuit
which caused intermittent stereo reception .