Let me end the Premp/Amplifier sound debate ...

Audiophile meaning : Wikipedia : Is a person who is enthusiastic about high fidelity sound reproduction. Seeks to reproduce the sound of a live musical performance. There are other definitions if you google it. My addition to this meaning, is that this person is willing to spend much money on the gear, and likes the gear, as much, and sometimes more, than the music itself. Enjoy !

Congratulations 

I went through this three years ago when I relocated 

I’m released from expensive cable  amps pre amp etc etc etc

I’m free and enjoying MUSIC! 

I just re equipped a listening room for a mere fraction of one of my past

 and just thrilled!

 

 

If wire has audible differences in direction as demonstrated here, logically all electronics including preamps and amps will sound different.

https://youtu.be/-P6TrQTuqMo

 

Atmasphere,

If the 15 dB of negative feedback was meant for discussion of the Melton MKT-88 tube amp used in the videos, I have no idea where you came up with this figure.

Melton advertises 0 dB of negative feedback, and doesn’t appear to have any components in a feedback loop when the chassis wiring is viewed.

 

 

MKT88P-80W

Integrated Amplifier

• Description

Product Description Specifications: Model: MKT88P-80W (Push Ball)

Power Output: 80 watt x 2 Output Impedance: 4.8.16 Ohm Amplifying Tube: 12AT7 x 2 pcs, 12AU7 x 2 pcs Power Tube: KT-88 x 4 pcs Rectifier Tube: 5Z4P x 2 pcs

 

** Tetrode Amplifier Design **

** No negative Feedback Design **

** Vacuum Tube Rectifier Design **

Superbly built integrated tube (KT88) amplifier.. .It employs specially designed simple circuitry for the well known Tetrode KT88 to make it sound at its best performance, coupled with powerful power supply and non-negative feedback design, capable of delivering lucid, melodiac, powerful sound with broad open soundstage.

 

 

You do not need to spend alot of money to get well designed and well built gear. Example: Many old recievers from the 70s, still work fine and sound for the age. My experience was with Crown home stereo equipment from about 1980. It lasted and still sounded better than many $1000 brand new high tech gear. This was 45 year old preamp and power amp matched set. Well built, absolutely!

Now, we get to sound. Completely yours. Between your ears, your brain, what you like in sound. Who gives a rip what Joe blow next door or on Audiogon thinks. The enjoyment of hi-fi is personal. Discussions are fun and educational.  I did get new gear I am thrilled with.  I went integrated tube, BS node 2, innous.  All relatively cheap compared with gear mentioned on this forum.

Nice job ending the debate!

@actaman -

             SOUNDLY, at that!

There is no debate. Amplifiers have been commodities for years. They can be built as tone controls but...

Anyone who as ever listened to a world class amplifier knows that this discussion is baloney.

The biggest takeaway from this thread is that @atmasphere has the patience of a saint. 

@erik_squires interesting OP! Given the differences I hear in these similarly measuring devices and manufacturer's not publishing the nuances that Ralph alluded to, I guess some of us are going to trust our ears. Cheers,

Spencer

I would think the biggest difference would be how differently speakers sound.  I would think when you buy larger size speakers that's when you need more power to drive them effortlessly.  That is when I would think you would need to find a more powerful amp to drive them.  The less an amplifier has to work the lesser the distortion.  I am not an electrical engineer nor know as much as most of you.  I am just a beginner.  However, I do think you need to reach a point where good is good enough and then concentrate on the music.  I still wish I could get the same sound as my Harmon Kardon car stereo.  The only thing it is missing is the crisp highs.  That said, most of us have lost some of our ability to hear the higher frequencies.  I think that is when we start shopping for new speakers that provide a greater amount of high frequencies.  Bench tests are one thing, but our years tell it all.  We just know when we like what we hear.  However, someone else hearing our sound system may not like the way it sounds as much as we do.  

Did it end yet?

@mapman 

Yes it did. Then it went off the rails and went somewhere else. 😂

Ended on the opening post...

Ended on the opening post...

At long last, a student of logic.  @ieales 

The only amps that don't have a sound are those that are turned off.

…and Benchmark’s amps. 

 

 

 

This seems to be an endless circular discussion. So let me cut to the chase. More expensive gear-- beyond a certain parts and build quality is bling, not better. 

I know plenty of high net-worth folks due to my line of work, and what I have noticed with respect to luxury purchases is pretty simple-- those that actually made their money -- a minority (about 80% of all wealth is inherited not earned)-- will spend on quality and, to a person, would never drop $50k on a DAC (it's stupid when you actually get into the costs and what's inside them) because they can "feel" that purchase-- they earned that money by actually working for it. So they care about what they're actually buying-- they tend to want quality over "bling".

A $100k amp, aside from the fancy case work, is no better than $5k-$10k amps of a similar power rating and type (SS or tubes). It's just a mixture of BS and bling.

Now those I'm friendly with that got their money the old fashioned way-- mom and dad GAVE IT TO THEM-- those folks will spend big on whatever the thing is-- a $50k wrist watch, a $300k car, or a $10k power cable, because to those that never earned it, there is very little difference between $5k and $50k when making a purchase-- in their minds it's all pretty much FREE STUFF!

The truth is, virtually no one, NO ONE, will be able to rank similarly spec'd amps from most to least expensive by judging the sound quality alone, assuming they fit the equipment profile of the rest of the components in that particular system.

No one will be able to price rank interconnect cables that range from a few hundred to many thousands of dollars each based upon sound quality. No one.

Everyone will hear differences. No one will be able to quantify those differences based upon price alone. No one.

I have offered to setup a test to prove this, but in fact this has already been proven over and over.

Just because you think you hear something does not make it so, and this is easily proven in tests. Ever heard of the placebo effect? It's real. So is confirmation bias.

Bottom line-- buy whatever you want to, but don't kid yourself that by spending the stupid money that you are getting or hearing better quality audio-- in fact this is almost never the case. You're hearing small differences that you will never be able to equate to the price (again assuming similar specs and a level of parts and build quality).

There are so many charlatans in this hobby that mark up their products to astronomical levels because they know this bias is real and that it can lead to some nice obscene profit margins-- and every business doing this will have an excuse for why they price gouge. $50k for DAC in a nice box that has maybe, MAYBE $5k worth of parts in it is, TO ME, a laughable rip-off that I would never waste my hard earned money on-- while to some of my friends, it's just a little something they bought with Daddy's (or grandma's, or their rich uncle's), money.

This hobby is supposed to be about the music, but it so often just becomes a pissing contest about whose bling is bigger.  Bling isn't bigger or smaller, it's just BLING.

To date, I've yet to see a tube amp measurement that does not look similar to the Black Line into the Stereophile simulated speaker load. Many speakers' impedance curves make the Simulated load look like a resistor.

Have you looked? As long as the speaker impedance does not go well below 4 Ohms, 15dB should be sufficient feedback to allow most tube amps to act as a voltage source within limits.

If the 15 dB of negative feedback was meant for discussion of the Melton MKT-88 tube amp

@toddalin I did not have the Melton in mind.

If a tube amplifier is able to act as a voltage source, how it does it is by cutting its power in half as impedance is doubled and not the other way 'round. This means that to get proper voltage response with some speakers and some speaker loads (aka Stereophile) you might have to use the 4 Ohm tap. You can see that this is one of the ways that tube power is more expensive than solid state power.

15dB is enough feedback that the output impedance of most transformer coupled amplifiers will be less than 0.1Ohm. Since most speakers do not need a damping factor of more than 10:1 (some need 20:1) you can see that this will work out just fine.

The problem IMO is that 15dB isn't enough feedback- it will add distortion of its own (mostly higher ordered, causing brightness and harshness) as a result. This is why feedback has a bad rap. But if you can get over the hump with enough feedback, then the circuit will be able to clean up those higher orders that feedback otherwise produces.

 

 

Have you looked?

For decades...

Most tube amp manufacturers these days seem to eschew lots of feedback.

FWIW, I've never measured a tube amp output voltage into a loudspeaker that was anywhere close to what an SS amp delivered into the same load... going back to the 70's. Admittedly, it's a small sample, and largely irrelevant as measurements mostly don't mean diddly. 😎

FWIW, I've never measured a tube amp output voltage into a loudspeaker that was anywhere close to what an SS amp delivered into the same load... going back to the 70's. Admittedly, it's a small sample, and largely irrelevant as measurements mostly don't mean diddly. 😎

Maybe I am simple fellow… but how can the sound (SPL) be the same, if the current (and voltage) are not the same?

FWIW, I've never measured a tube amp output voltage into a loudspeaker that was anywhere close to what an SS amp delivered into the same load... going back to the 70's. Admittedly, it's a small sample, and largely irrelevant as measurements mostly don't mean diddly. 😎

Its not that the measurements don't mean anything, its that the measurements have to be performed correctly, and the important measurements have to be made (the latter rarely happens, which has lead to the myth that we can hear things we can't measure...).

 

Maybe I am simple fellow… but how can the sound (SPL) be the same, if the current (and voltage) are not the same?

 

Its a good question. If a given amp is making 10 watts into a certain speaker at a certain frequency and has an output impedance of 0.01 Ohms, and another amp can make the same power at the same frequency and into the same load, while having an output impedance of 1 Ohm, since both amps are making the same power, the voltage and current will be the same.

The output impedance can affect FR and distortion but it won't affect output power since the example has that aspect being the same. If it really is the same the current and voltage has to be the same too.

Pool size and sample variation play a role here.

If you had happened upon Amir’s site in the early days after he had measured just two amps (or DACs) the different measurements would be very noticeable when presented on a graph graphic. After eight or so component tests that graph would have an obvious curve to it.

But, take a look at that graph now (after dozens and dozens of tests) and what do you see: that graph has flattened out. If he continues and eventually tests thousands of boxes that curve will continue to flatten to the point that it will look like a straight line. 
 

One camp could then say “they still all sound alike”. And the other camp could say “they all measure alike”. 
 

Does this all matter? Perhaps only when doing small sample size comparisons, like direct A:B tests at home, which is really the ony practical way of evaluating purchase options…
 

 

This, on the OP’s leading post, says a lot:

Be true to yourself, but I find very little on earth less worthwhile than having arguments about measurements vs. sound quality and value. 

It is not like measurements are not largely correlated with preferences.
And it is not like engineers aren’t using measurements in the process of design and quality control.

They measure the living $hit out things, and they know which measurements to be doing.
If they were not, and if people did not care, then we would all be running Class-B amps. But people do not usually enjoy crossover distortion, so we have Class-A, tubes, and highly biased class-AB… as well as Class-D.

It does not matter how many measurements we do, people do not enjoy crossover distortion. And that number of people is linear with the pool size of people chosen.

Maybe I am simple fellow… but how can the sound (SPL) be the same, if the current (and voltage) are not the same?

There’s much more to sound than SPL.

Mostly, the measurements quoted in HiFi are THD and IM @ a power level.

Occasionally, a square wave or distortion spectra.

ALL into a resistor, not a dynamic loudspeaker load.

This series of frequencies into an 8Ω load resistor gives an idea of the Phase Shift in a tube amplifier output transformer @ 10W RMS. The ear is extremely sensitive to phase, but hardly anyone mentions it. Ideally all lines should look like 200Hz & 2kHz as 45° lines. Nobody publishes anything other simple meaningless measurements that the untrained can lap up.

20Hz.jpg (566×477) (ielogical.com)

200Hz.jpg (566×477) (ielogical.com)

2kHz.jpg (566×477) (ielogical.com)

20kHz.jpg (566×477) (ielogical.com)

200kHz.jpg (566×477) (ielogical.com)

A solid state amp would do much better.

This series of frequencies into an 8Ω load resistor gives an idea of the Phase Shift in a tube amplifier output transformer @ 10W RMS. The ear is extremely sensitive to phase, but hardly anyone mentions it.

The ear is only sensitive to phase when it covers a spectrum of frequencies. It cannot tell phase of a single frequency.

FWIW our OTLs have 0 degrees of phase shift at 20Hz to 20KHz. Phase shift at 200KHz isn't a concern. So a tube amp can do much better too 😉

Your answer does not appear to address the question posed.

Music is a sequence of fundamentals rich in harmonics. The ear brain can definitely tell when the harmonics are shifted.

OTL - Output TransformerLESS - is off topic. The images are for "tube amplifier output transformer". Let’s take it as written that atmasphere makes fine amps.

The question was about current and voltage. The current and voltage cannot be the same if the harmonics are temporally shifted relative to the fundamental.

@ieales

There’s much more to sound than SPL.

That snippet you took was out of a response to your post about SS and tube amps not making the same voltage.

Are you saying the voltage is proportional to something other than SPL?
Or what does the voltage of tube versus SS have to do with the sound?

You say that the ear is sensitive to phase. Which speakers are you using and are they providing some well behaved phase response?

All these amps sound EXACTLY the same........When turned off!

 

@holmz

If a single frequency SPL is measured with the same terminal voltage, that SPL should be the same for any amp.

Since almost agree that tubes sound different than solid state, then what makes up the ’voltage’ must vary. So if you measure 1kHz 2.83v at the speaker, an SS amp could be 99.999% 1kHz. A tube amp may be 99.5% 1kHz, 0.25% 2kHz, 0.05% 3kHz, etc. Additionally, depending on the amp and system, there could be PSU or loop components. An FFT of the captured output could be revealing.

There fore, depending on the equipment and pertaining to the suggestion to measure the terminal voltage to match levels, is that the program SPL may not be the same with the same measured voltage assumed to be made at a reference frequency.

Since the early 70’s I’ve had time coherent speakers: Dalhquist DQ-10, KEF 105 MkII, BiAmp Magnepan Tympany IV. From 1987 to 2020, I used Spica TC-50, which were the speakers I carried around to studios. The TC-50 was the first box speaker I heard that more correctly presented the phase coherence that I first heard on Quad 57s. and were able to correctly produce what I heard on time corrected BIG monitors in recording studios. I bought the TC-50 without asking the price or knowing anything about them as they were the first small monitor I’d heard that came close to presenting the recorded sound field. Since 2020, I’ve used Eminent Tech LFT8b’s, triamped with time alignment via miniDSP. The speakers can produce a tolerable facsimile of a square wave. And then I screw it up with tubes.

The question was about current and voltage. The current and voltage cannot be the same if the harmonics are temporally shifted relative to the fundamental.

Since almost agree that tubes sound different than solid state, then what makes up the ’voltage’ must vary.

If you put a solid state amp and a tube amp on the bench, both might measure quite flat- the H/K Citation 2 is a good example. One amp might sound bright while the other does not. But if you measure the output at the frequencies where the bright amp sounds that way, you'll see that the power can be the same as the amp that is not bright (likely the tube amp).

The difference in sound is higher ordered harmonics which tend to be audible with most solid state amps (audiophiles have been hearing this problem for the last 60 years, which has kept the tube industry alive), and the ear is both keenly sensitive to these harmonics (it uses them to sense sound pressure) and assigns a tonality (as it does for all forms of distortion) of 'bright and harsh'.

Yet at any given frequency, for a given amount of power into a given load (8 Ohms for example) the voltage and current will be the same on account on the power formula (1 Watt= 1 Amp times 1 Volt). This is a simple fact that cannot be undone. The difference you hear isn't on account of power! Its on account of the distortion signature, which is simply too little energy to show up when measuring voltage and current.

The big reveal here is that distortion is always audible! The ear has over a 120dB range and since it uses higher ordered harmonics to know how loud a sound is, its sensitivity to those harmonics is paramount, but poorly understood by audiophiles and engineers alike. Yet that is the main difference you hear between tube and solid state.

The difference you hear isn't on account of power!

Yes it is.

It's not that the distortion signature is too small, it's that no one measures it. No SPL meter is going to be better than ±0.1db @ 85dB. It likely has a nonlinear response. In absolute terms, it's not even close.

Back in the 80's Bob Carver tweaked an amp to sound exactly like another: The Carver Challenge | Stereophile.com

FWIW, we gave up on matched level listening tests in the 70's simply because it's about as worthless reading the spec sheet. An amplifier is but one component in a system. Change one thing, change everything. I think it's stood me in good stead when a guitarist says "Joe Pass is sitting RIGHT THERE!"

@ieales , @atmasphere is absolutely correct. Debating opinion and supposition with facts presented by one of the foremost authorities on the subject is rather futile. You may wear down his willingness to contribute to educating others on the subject but you won't change the facts. @atmasphere is universally respected by amplifier designers, be they solid state or tube gear designers, who are universally respected.

It's not that the distortion signature is too small, it's that no one measures it. No SPL meter is going to be better than ±0.1db @ 85dB. It likely has a nonlinear response. In absolute terms, it's not even close.

It gets measured alright. But I think I see what the confusion is. An SPL meter is only useful if the speaker is making sound, whereas we've been talking about measured output power. The two are not the same, owing to tube amps having a slightly higher output impedance in most cases- that will cause minor FR errors. My prior statement in this regard is correct:

at any given frequency, for a given amount of power into a given load (8 Ohms for example) the voltage and current will be the same on account on the power formula (1 Watt= 1 Amp times 1 Volt).

 

Back in the 80's Bob Carver tweaked an amp to sound exactly like another: The Carver Challenge | Stereophile.com

I remember that. He failed too; a 35dB match was all he could get.

FWIW, we gave up on matched level listening tests in the 70's simply because it's about as worthless reading the spec sheet.

If one amp was making more higher ordered harmonics, it likely would have sounded louder. An SPL meter gets to the bottom of that pretty quickly.

Don't conflate the spec sheets with the measurements. Spec sheets are IMO the Emperor's New Clothes. Measurements are not.

 

 

 

"The Final Achievement
After this last bit of tweaking, where Bob was able to reinstate his 70dB null while driving a very difficult load, we now had what sounded like two absolutely identical amplifiers." [emphasis added]

 

If one amp was making more higher ordered harmonics, it likely would have sounded louder. An SPL meter gets to the bottom of that pretty quickly.

¿Que? Loudness? Never mentioned it. We were matching level w SPL meter @ 1Khz and Pink Noise and also measuring amplifier voltage output w AC voltmeter. Some amplifiers were sonically very close and some not. Some better with one speaker and others with another. In the end, we came to the conclusion that synergy exists and it's not predictable.

Spec sheets report measurements, or at least some do. 😉

@ieales

FWIW, I’ve never measured a tube amp output voltage into a loudspeaker that was anywhere close to what an SS amp delivered into the same load... going back to the 70’s. Admittedly, it’s a small sample, and largely irrelevant as measurements mostly don’t mean diddly. 😎

if the voltage is within, say 10%, then the SPL will be also be very close.

 

 

Yes it is.

It’s not that the distortion signature is too small, it’s that no one measures it.

BS - it is measured ad naseum, and produces nausea in people that do not understand it.

 

No SPL meter is going to be better than ±0.1db @ 85dB. It likely has a nonlinear response. In absolute terms, it’s not even close.

BS - most people probably max out at 0.5 to 1 dB difference.
So getting the two systems within a fraction of a dB is a great start to a controlled listening test.

And I further disagree as I have the NIOSH app on my iPad as many low distortion speakers do not sound like they have a lot of SPL happening.
Then when I turn to someone in the room, we have to shout to hear each other… and when I look at the app says 90dB or more.

However on my wife’s old system it sounds loud at 65dB.
On my old system at about 95dB.
And on some state of the art systems mote like 100+ dB before it “SOUNDS” loud.

 

Back in the 80’s Bob Carver tweaked an amp to sound exactly like another: The Carver Challenge | Stereophile.com

FWIW, we gave up on matched level listening tests in the 70’s simply because it’s about as worthless reading the spec sheet. An amplifier is but one component in a system. Change one thing, change everything. I think it’s stood me in good stead when a guitarist says "Joe Pass is sitting RIGHT THERE!"

I trust Bob Carver about as much as a preacher.

1. He had some good designs, back in the day, but he’s prone to hyperbole and wild eyed ranting.
2. Some of his current designs do not meet specs and appear to be dangerous to safely use.

 

Other the other hand I have heard only good things about Ralph, and his writing indicates that he is learned in the subject and is rationally presented.

 

Lastly the use of the word “Synergy” has a magical tone to it, that to me is sort of like a synergy of faults summing to zero.

(IMO) It is easier to build systems were output impedances are low, input impedances are high, the FR and PR is flat… than spicing up bright and warm gear like a sweet-n-sour pork where things are starting out in major conflict.

There is difference between any piece of gear and any other one generally and in most cases for many reasons...It is common place experience...

Dont ask for a blind test please... 😁😊

There is also acoustic conditions which OFTEN make difference in gear minute one compared to room control...

And if you want good S.Q. buy first and to begin with some good gear....It is not so difficult because electronic audio engineering is mature technology for many DECADES... 70 years ? or 60 ? or 50 ? We must ask atmasphere for that, he knows....

But nothing will rival acoustic control and treatment to optimize and put your well chosen gear ON HIS PEAK WORKING POTENTIAL... NOTHING....

Certainly not upgrading a good piece of gear already for an alleged "better" one because of publicity by reviewers...

What we hear at the end is acoustically determined anyway ...A bad amplifier compared to a good one will not be changed by the room control in a good one for sure...but any good one will be TRANSFORMED in a miraculously good one...

All basic good design of amplifier and speakers are the starting point not the destination... Acoustic is the key....Nothing else...

i sell acoustic creativity not gear....

 

 

i concur with this post:

"If it measures good and sounds bad, –– it is bad. If it sounds good and measures bad, –– you’ve measured the wrong thing." –– Daniel R. von Recklinghausen, HHScott

The only measurement that matters is how it sounds in your system in your room with your program. Evaluation by any other method is foolish unless you are buying HiFi Jewelry or Furniture.

 

@mahgister it does not matter how well one treats a room in terms of the direct path sound.
If that sound is filled with distortions, then no amount of room treatments can work by going backwards in time to remove the distortions.

One would hear the direct path sound before any reflections arrive. Whether or not those reflections are high level or super reduced.

While the room may be important, it is not going to fix the amplifier.

Try to understand my point without repeating a common place evidence...

A bad electronic design or a corrupted source CANNOT be compensated or repaired by a room acoustic...

Who does not know that? Who? 😁😊😎

 

My point is that acoustic control method are more powerful than most upgrade

Of gear....

My second point is acoustic is the way, in most case, to transform your system and put it on another level : his true peak working optimal potential.... High quality sound experience is not the AUTOMATIC result after buying a 100,000 bucks piece of gear to replace a 50,000 one... Sorry if you dont know that... 😁😊

 

It is very easy to buy a good amplifier to begin with...Because electronical audio design is mature industry with good products available...

My point is when you have basic good gear the REAL WORK begin, and it is not upgrading to improve MORE because of your " taste" ... Sorry! If acoustic cannot improve a bad quality design, buying and plugging will not replace acoustic... 😁

It is studying acoustic et experimenting with it which is the way and the only way...And especially understanding psycho-acoustic also a bit....

Who dare to say that in audio forum? Me and very few others...

Almost all sell their "taste" in gear all over the place ignoring acoustic....

What i claim is not a common place fact like what you just say... It is a scientific fact: it is acoustic and psycho-acoustic which can explain almost all of  our audio experience...

This does not means that all amplifiers sound the same or speakers...Not at all for sure...

This means the main method to listen to the gear you already own it is putting it in an acoustically controlled room... If not, you will never know how your system can sound in optimal conditions and the difference is HUGE.. It is not an opinion here on my part, it is my experience... Not a common place fact at all because most people have no experience with acoustic anyway...Or very little because in small room passive  treatment is not always  enough to create immersive filling the room sound experience...It takes active mechanical control with Helmholtz resonators AND DIFFUSERS...

it is the reason why i insist about that...

And anyway acoustic in a dedicated room can cost peanuts , i proved it to myself...

I say all that to alert newcomers and advise them to think before throwing money...

Most people here are not bankers or billionaires able to buy and plug without even thinking... All people are not able to afford a pro acoustical dedicated room either...

It is possible to create one at very low cost...

Then i sell hope and creativity and acoustic science...

Who say better?

 

@mahgister it does not matter how well one treats a room in terms of the direct path sound.
If that sound is filled with distortions, then no amount of room treatments can work by going backwards in time to remove the distortions.

One would hear the direct path sound before any reflections arrive. Whether or not those reflections are high level or super reduced.

While the room may be important, it is not going to fix the amplifier.

 

 

 

Try to understand my point without repeating a common place evidence...

A bad electronic design or a corrupted source CANNOT be compensated or repaired by a room acoustic...

Who does not know that? Who? 😁😊😎

Ok @mahgister I get the room stuff, it was just that a lot of the recent posts were on distortion and it being something that differentiates one amp from another.

Sorry that I thought you were tying the acoustic room stuff with the amp distortion.

While amp circuits may lead to very similar outcomes there are vast differences in power supplies. And Ralphs argument on differential harmonics between Tubes and SS certainly concurs with what I hear

@holmz +1 My thoughts exactly. that Stereophile nonsense caused me to suspect Mr. Carver so many years ago; the latest debacle with an amplifier that can't make anywhere near full power sealed the deal IMO.

And if you want good S.Q. buy first and to begin with some good gear....It is not so difficult because electronic audio engineering is mature technology for many DECADES... 70 years ? or 60 ? or 50 ? We must ask atmasphere for that, he knows....

Its nice to think audio is a mature technology. But its no-where near as mature as people like to think. If it was, tubes would not still be around; solid state circuits would have replaced them and no looking back (as happens in any field where the new tech replaces the prior art). The problem has been that the semiconductors needed to really supplant tubes (meaning: to make a solid state amp that isn't harsh) didn't exist in the 1970s or 1980s. We had a proper understanding of control theory in that time, but oddly, didn't apply it to audio (probably because if that was actually a goal, no power amplifiers would have been produced 😁). So feedback networks for the most part have been poorly designed and we have several decades worth of solid state amps that come off harsh and bright, especially when you turn it up. IMO this is mostly because the gear was made to make money so the companies making it didn't care that it fell well short of the goal of sounding like real music. Sorry to sound curmudgeonly...

This has been what has kept tube amplifiers in business the last 70 years since they do offer a way around this issue (they make enough lower ordered harmonics to mask the harshness of the higher orders they also make).

But in more recent times semiconductors have advanced to the point where you can get rid of that pesky brightness/harshness for which solid state is known. IMO we've only just arrived near the top of the R&D sigmoid curve in audio in the last ten years or so.

Thanks very much atmasphere for your knowledge...

I was hoping your explanation to confirm my point...

I could not explain all the details like you did...

In a word there is tube amplifiers and some S.S. which were never bright or harsh, like my Sansui AU7700 and some new technology now for the last decade...

My point is that there is now available many good different types of amplifiers... Yours for sure and some others...

It is more easy to look for one and buy it now than to solve all acoustic problems for us...

My point is acoustic is the key to optimize and put at their   peak level ANY amplifiers working PERCEIVED EXPERIENCE in a room  in a way that is astounding, not a minute upgrade...

Thanks to you for your useful post...

This has been what has kept tube amplifiers in business the last 70 years since they do offer a way around this issue (they make enough lower ordered harmonics to mask the harshness of the higher orders they also make).

But in more recent times semiconductors have advanced to the point where you can get rid of that pesky brightness/harshness for which solid state is known. IMO we’ve only just arrived near the top of the R&D sigmoid curve in audio in the last ten years or so.

Someone ends a debate but has no interest in debating. Funny. 

 

And I further disagree as I have the NIOSH app on my iPad

No mention of calibrated microphone or calibration standard. Both are necessary.

 

I trust Bob Carver about as much as a preacher.

Carver made the claim, the Doubting Thomases verified he did what he said he could. 

 

I have heard only good things about Ralph

AFAIR, I've only ever said nice things about Ralph and atmasphere. He's a smart guy and his products are very good.

 

While amp circuits may lead to very similar outcomes there are vast differences in power supplies.

Spot on. Many designers don't understand that the amplifier circuitry is a power supply regulator. If the PSU dynamic response is bad, then that will manifest itself in the output.

 

The problem has been that the semiconductors needed to really supplant tubes (meaning: to make a solid state amp that isn't harsh) didn't exist in the 1970s or 1980s.

V-FETs. Sony and Yamaha made some gorgeous sounding amplifiers that cost a fortune.  AND plenty of good ideas that advanced the SOTA. And there are plenty of audio products currently manufactured that make one shake one's head and wonder "What were they thinking?"

 

This has been what has kept tube amplifiers in business the last 70 years since they do offer a way around this issue (they make enough lower ordered harmonics to mask the harshness of the higher orders they also make).

Harmonics, phase response, transient response, compression, dynamic noise spectra, damping factor, glowing sexy glass bottles, emotional involvement adjusting bias, tube rolling, ad infinitum...

 

IMO we've only just arrived near the top of the R&D sigmoid curve in audio in the last ten years or so.

If we are near the top, are we about to start a slide down in a short while as Handy suggests? From my perspective, apart from the bling factor which is lamentably far to prevalent, audio improvement proceeds apace.

@ieales has mentioned, those V-FET amplifiers sounded very nice ( I owned a Yam B2 ), and I regret selling it ( it needed an over hall and rebuild, and I did not want to do it at that time ( the v-fets were fine ). I have many regrets of gear I had let go......a different story, for another time.....Enjoy !