Are tubes more musical?

[Multicore]

There's probably still a market for record albums (on some sort of media, maybe even streaming) of the kind that launched -- yes -- Mobile Fidelity Sound Labs a long, long time ago.

Francisco López made his mark as a great artist with stuff like that.

 

[Timcognito]

There's probably still a market for record albums (on some sort of media, maybe even streaming) of the kind that launched -- yes -- Mobile Fidelity Sound Labs a long, long time ago.

Well they predate MF by decades. Somewhere I got a Living Stereo with vicious ping pong, dripping water and aircraft fly overs.

 

[mhardy6647]

Well they predate MF by decades. Somewhere I got a Living Stereo with vicious ping pong, dripping water and aircraft fly overs.

similar (within a few years) of the earliest "Mobile Fidelity" (predecessor to MFSL) albums -- did you see that PDF link?
Ping-pong stereo was a thing in the early days, as were the sound effects records.
There are a few here -- I know, inconceivable, right?

 

[Timcognito]

did you see that PDF link?

Missed it. My bad. Too busy being a wise guy. Will visit next.

 

[Timcognito]

There's probably still a market for record albums (on some sort of media, maybe even streaming) of the kind that launched -- yes -- Mobile Fidelity Sound Labs a long, long time ago.

View attachment 397920
Yes, it's an LP of choo-choos and thunderboomers.

Mobile Fidelity even predated that hoary chestnut above (from 1977, if memory serves) with choo-choo records from the early days of stereo LPs (1958).

View attachment 397923

https://www.friktech.com/labels/EarlyMobileFidelity.pdf

Cool now in search of

bet in won't be $4.98

 

[Multicore]

Ping-pong stereo was a thing in the early days, as were the sound effects records.
There are a few here -- I know, inconceivable, right?

Galileo. Galileo.
Galileo. Galileo.
Galileo. Galileo.
Galileo Figaro.

 

[jayapple]

I wouldn't say so. For me the point of engineering high performance audio gear is so that it gets out of the way of the music.


Seems you're the one listening to the equipment instead of the music, not me.

Even so, it is well known that tube amplifiers and Class D amplifiers do sound different.
Class D high efficiency low distortion. tube amplifiers have unique distortions, and some well-designed light bulbs are worth a lot of money, more for emotional value.

If you are a pure listener of music, you should not care about the equipment, whether it is Class D, Class AB or tube amplifier can produce sound.

I admit that I like to use different amps.
tube amplifiers can be homemade, and changing the light bulb is just a fun part of listening to music.

 

[jayapple]

Even so, it is well known that tube amplifiers and Class D amplifiers do sound different.
Class D high efficiency low distortion. tube amplifiers have unique distortions, and some well-designed light bulbs are worth a lot of money, more for emotional value.

If you are a pure listener of music, you should not care about the equipment, whether it is Class D, Class AB or tube amplifier can produce sound.

I admit that I like to use different amps.
tube amplifiers can be homemade, and changing the light bulb is just a fun part of listening to music.

Another interesting phenomenon is that the sales of Class D amplifiers in China are very low, and many people do not trust the small box like FOSI, and often the comments are not good.

I don't know what it's like elsewhere, people tend to buy those glowing bulbs or some outdated replica design, even though the price of such products is much higher than FOSI.

 

[Bruce Morgen]

I have found that certain vacuum tubes, particular vintage examples from the U.S., the UK, and Germany, have a distinct and enjoyable sound that no solid-state component can achieve. E.g., tapping a vintage RCA or GE "coke bottle" 6L6G with a (preferably ivory or bone) chopstick can provide the best on-the-beat percussion sound this side of top-notch cowbell!

 

[solderdude]

Even so, it is well known that tube amplifiers and Class D amplifiers do sound different.

You mean can sound different.
There are well extended and low (enough) output resistance and powerful well designed tube amps right up to total crap.
There are load dependent cheap class-D amps up to high-end not load dependent super amps.
There poor class AB amps right up to well designed power houses.

When you take any of the 3 poorer ones you will find sonic differences which one an owner prefers depends on the speakers, rooms it is used in and taste.
When you take any of the 3 better build ones, level match them and keep the power below clipping level of the lowest powered amp, compare them 'blind' and level matched it is guaranteed you cannot tell them apart.

 

[DanielT]

In that case I'm putting the Tiger comment up to a communication error. As I recall it was a painful amp.

cut 1: Algunas Bestias
cut 2: Sandino

Its been my theory that above 10KHz a distortion rise with frequency won't be heard for obvious reasons. So this has my interest piqued.

Citation needed; this appears a highly speculative and a rather subjective observation. FWIW, SET users (Single Ended Triode amps typically are zero feedback) commonly describe SETs are being more dynamic rather than less. Its my contention this is caused by how the amplifier distorts and how that in turn skews the ear's mechanism for sensing sound pressure (IOW, its an illusion). Actual, real dynamic qualities reside in the recording and are not actually a function of amplifiers whether tube or solid state.

'Rolled off response' makes no sense as many tube amps have wide bandwidth; that was a big deal with Stu Hegeman, the designer of early HK tube equipment including the Citation series. The Citation 2 of this thread has bandwidth that often goes higher than the published specifications, which can be regarded as nominal (I just put my Citation 2 on the bench and it easily made full power to 70KHz). The Citation 2 BTW employs enough feedback that it is able to act as a Voltage source as long as the load impedance does not get too low so FR variation is not a variable. Tube headphone amps tend to have much wider response and headphones tend to be a very easy load.

I commented earlier on the subjective quality of 'dynamics'.

A simple way to answer than of course is to obtain a good tube amplifier and find out. IME a side by side demo easily shows the difference to anyone in the room as its usually not subtle. The speakers used for such a demo should be of the kind that both the control amplifier and the tube amp both find to be an easy load so FR variation can be ruled out.

IME, these are the differences, which are easily measured:

1) more prodigious 2nd and 3rd harmonic than seen in most solid state amps; which the ear interprets as 'warmth'. I know some people think this is because of a hump in the bass or some such but if you put such amps on the bench you see there isn't anything like that unless the amp lacks feedback. If it lacks feedback the amp is meant to be used on a speaker that is designed with that in mind to prevent coloration.
2) A 'smoother more relaxed sound'; my theory being that the 2nd and 3rd harmonics are masking higher orders in the same way as seen in loudspeakers.
3) The reduced generation of higher orders at clipping, which allows for a graceful overload characteristic. Quite often people are overloading their tube amps and don't even know it. Guitar players in the past are well-known for using tube amplifiers for exactly the purpose of overdrive; that is how Marshall, Fender, Ampeg and so on made their names.

Once you really understand these facts it allows an access for designing and building a solid state amp that does the same thing should that be desired. You can even get the 3rd aspect of soft clipping if SITs are used in the output section. Its highly likely that a multi-ordered feedback loop will be needed and care in the circuit design should be taken to minimize distorting the feedback signal at the feedback node.

I forgot to ask you. You mention as more prodigious 2nd and 3rd harmonic than seen in most solid state amps; which the ear interprets as 'warmth
As a tube amp manufacturer, should the goal be to make these 2nd and 3rd harmonics audible or should you design a tube amp where these levels are moved to the inaudible range? If you aim for the latter, inaudible, then why even design a tube amp?

If, on the other hand, you want to make these 2nd and 3rd harmonics audible, how much distortion do you think you should have for it to sound good?
I mean what's the point of designing a tube amp with say 0.5% distortion at half power (20Hz-20kHz) if you can design it with 5%, or 10%. Or is 10% distortion too much and if so why?

Edit:
In the past, however, low distortion seemed to be a goal for tube amplifier designers. At least for D. T. N. Williamson who designed:

Williamson amplifier​

The Williamson amplifier is a four-stage, push-pull, Class A triode-output valve audio power amplifier designed by D. T. N. Williamson during World War II.

It had a modest output power rating of 15 Watts[a] but surpassed all contemporary designs in having very low harmonic distortion and intermodulation, flat frequency response throughout the audible frequency range, and effective damping of loudspeaker resonances. The 0.1% distortion figure of the Williamson amplifier became the criterion for high fidelity performance[2][3] that remains valid in the 21st century.[4]

Design targets​

edit
Following Cocking's ideas, Williamson devised a different, much stricter set of fidelity requirements:

1. Negligible non-linear distortion (sum of harmonic distortion and intermodulation products) up to the maximum rated output, at all audible frequencies from 10 to 20000 Hz;[19]

Williamson amplifier - Wikipedia

en.wikipedia.org

That amp was discussed in this thread:

Does anyone have a Williamson tube amplifier?

Or have had, listened to a Williamson tube amplifier? Impression? Are they available? What can one, in reasonable condition, cost? I could really imagine having one. Mostly for its HiFi history. :) Not as a main amp but in some nice secondary system. Then together with a subwoofer + LP/HP...

audiosciencereview.com

 

[Multicore]

If you are a pure listener of music, you should not care about the equipment, whether it is Class D, Class AB or tube amplifier can produce sound.

I don't. If I have to buy an amp then I have to concern myself with its performance and other practical matters. I really don't know or care much about the amps in my Genelec boxes because I trust the designers to have taken care of those matters.

I admit that I like to use different amps.
tube amplifiers can be homemade, and changing the light bulb is just a fun part of listening to music.

Nobody is arguing with how you choose to have fun. That's not the question in this thread.

 

[BDWoody]

Even so, it is well known that tube amplifiers and Class D amplifiers do sound different.

Bolding doesn't make it true...

It isn't well known at all, it is well assumed by many based on lots and lots of stories.

 

[DSJR]

FWIW, a comment we often see about solid state amps is they 'lack emotion; are dry and lifeless'. I've been hearing that feedback for over 35 years so I've come to think there's something to it. My theory is it has something to do with distortion- how H2 and H3 interact with the ear/brain system to create the illusion of more detail, richer sound, that sort of thing.

Got to butt in -

Amps I've owned, used and sold with a highly musical 'emotion-filled' sound and irrespective of what devices they use, tend to make *everything played through them* 'sound' much the same in my experience! The older-then-vintage pro amp I use mainly these days, did sound 'dryer' initially compared to other amps, even when I demmed this model new fifty years back. At home here and into a pretty easy load, I find that I can more easily here what's 'really' going on at the back of the music mix, reverb, venue-atmosphere and so on, which these 'musical-sounding' wonders just seem to smother...

 

[Gorgonzola]

OP says, "They seem to create a feeling of space and holographic imaging."

I'd like to hear comments on this effect which I (subjectively) have heard listening to tube preamp. In my case, tube "rolling" seemed to tune the effect, more or less depending on the tube used.

Pleasant though it might be, I have concluded that the "holographic" effect is an artifact, basically some sort of distortion. I love to hear some theories on how tube amplification creates the effect.

 

[Multicore]

FWIW, a comment we often see about solid state amps is they 'lack emotion; are dry and lifeless'. I've been hearing that feedback for over 35 years so I've come to think there's something to it. My theory is it has something to do with distortion- how H2 and H3 interact with the ear/brain system to create the illusion of more detail, richer sound, that sort of thing.

I've been holding back the following personal anecdote from my childhood.

I vividly recall a conversation with my father about exactly this form, I would guess, my mid teens around 1980. I don't remember how and where I picked it up but I related to him this story I'd heard that tubes have a more pleasing clipping behavior since they produce more of the even harmonics than the transistors which produce more of the odd. I knew enough about Fourier series sums and harmonic overtones at that time (as an curious and experimental electric guitarist) to believe I knew what I was talking about.

My father, an audiophile and music lover of the previous generation with scrap Quad ELS and tube amps in the garage and diploma in electrical engineering(*), who could and did design and build electronic gear and could repair the TV using a Heathkit scope that my mother had built while she was pregnant with my older sister, looked at me askance and asked a question about my theory that made me feel defensive and foolish.

It's my oldest and best memory of getting caught with my pants down singing something from the audiophile hymnal.

(*) He switched to hydraulics fairly early in his career and by the time of this anecdote was doing CFD on a home-built Z80 programmed by my mother who had been in the first wave of professional computer programmers in the country before having kids.

 

[atmasphere]

I'd assume they are still around, because some people (like with Nixie clocks), like the way they look. I assume some people think they like or like the way they sound.

IIRC Stereophile did a study which showed that if the equipment had gold panels people thought it sounded 'warmer'. But in the case of tubes it actually is more than that

Say what you want, but this thing with tube amps and their being or not always takes off.

That simple fact is evidence that not all solid state in the past has brought home the bacon. I doubt this will ever get seriously researched so its down to conversations on audio websites, which IMO/IME usually fail to get to the nub of it, so the conversation has been ongoing since the inception of the Internet (which preceeds the WWW).

So I'll ask again- since the Adcom 565 does NOT show the behavior you were talking about, are you good with using the SWTP Tiger as the model? You indicated it before, but then seem to have backed off it. If not that, name an engineered solid state amp which you will attest is "bright" so the model can be built. If, as you have been claiming, this is a fundamental characteristic of ss amps, this should be easy. Why are you avoiding it?

Lined out portions are false; snipped portion is a violation of website posting rules so is not repeated to avoid owning the violation.

I forgot to ask you. You mention as more prodigious 2nd and 3rd harmonic than seen in most solid state amps; which the ear interprets as 'warmth
As a tube amp manufacturer, should the goal be to make these 2nd and 3rd harmonics audible or should you design a tube amp where these levels are moved to the inaudible range? If you aim for the latter, inaudible, then why even design a tube amp?

If, on the other hand, you want to make these 2nd and 3rd harmonics audible, how much distortion do you think you should have for it to sound good?
I mean what's the point of designing a tube amp with say 0.5% distortion at half power (20Hz-20kHz) if you can design it with 5%, or 10%. Or is 10% distortion too much and if so why?

[snip]

I think 10%, even if mostly 2nd harmonic, is too much. That is one reason I'm not a fan of SETs. Not the only reason by any stretch... an elliptical load line is no way to run a power tube, you can't make bass with any power (or the OPT would be the size of a small refrigerator to get the inductance needed). There's a really good reason PP amps supplanted them. I don't want to digress on this, its easy to get me started on the failings of SETs.

I never set out to make the 2nd and 3rd audible (nor do I know any designer who does that with intention) and made our tube amps fully differential in order to cancel even orders throughout the circuit (so tend to produce a dominant H3 rather than H2). I see it sort of the other way around, which is tubes need to go away and to that effect, solid state amp designers need to make their amps 'sound' correct such that tube amp users will abandon the tube amps for something better. Keeping in mind of course that tube amp users tend to own tube amps based on 'sound'.

I think this is happening right now- a lot of the current crop I'm seeing have what I think is the right distortion spectrum, don't have distortion rise with frequency and lower THD so should be greater detail (since distortion obscures detail IME) and just as relaxed as the best tube amps. FWIW, tube users often have complained over the years that solid state amps have more detail but that comes with brightness- so much so they conflate the two! I think you're on the right path when you get both detail and a relaxed presentation at the same time. BTW if you've not seen it, Bruno Putzeys, who had one of the lowest distortion amps ever, just did himself one better! BTW, apparently Bruno thinks the way I do about all this, if we are to take some comments on the Purifi website seriously (note 'harsh sound').

I love your 2nd question! I ask people the same thing- if you can get all the benefits you associate with tubes (greater detail, relaxed, smoother presentation, the ability to listen all day yada yada) in a solid state amp, why do tubes?? They are more expensive, noisier, more heat, less reliability, warm up time (which might take over an hour)...

3rd question: 0.1% is plenty!! 5 or 10% is too much as you lose low level detail- its harder to make out vocals, stuff in the background and so on. All very subjective stuff here of course, but I hear about it all the time.

 

[BDWoody]

'. But in the case of tubes it actually is more than that

All we need now is actual, meaningful evidence, not more claims and stories.

. I doubt this will ever get seriously researched so its down to conversations on audio websites,

There seems to be a reluctance from those who rely on conversations on audio websites to help remedy that. Here, we have some very well qualified folks, including a physics professor and amp designer in his own right willing to help change that, so hopefully those who make claims as above might want to help.

Stuart is not breaking forum rules by being very direct with you. This has been going on for years now, yet it seems we are still where we started. I hope there can be an agreement on terms so we can all be shown that there is more to it. Or not.

If a well known, well respected amp designer (you) can't do this, with testing designed to actually have enough rigor to be meaningful, who can we expect to do it?

Is it all just going to be marketing and propaganda? Sure reads like it.

 

[SIY]

IIRC Stereophile did a study which showed that if the equipment had gold panels people thought it sounded 'warmer'. But in the case of tubes it actually is more than that

That simple fact is evidence that not all solid state in the past has brought home the bacon. I doubt this will ever get seriously researched so its down to conversations on audio websites, which IMO/IME usually fail to get to the nub of it, so the conversation has been ongoing since the inception of the Internet (which preceeds the WWW).

Lined out portions are false; snipped portion is a violation of website posting rules so is not repeated to avoid owning the violation.

I think 10%, even if mostly 2nd harmonic, is too much. That is one reason I'm not a fan of SETs. Not the only reason by any stretch... an elliptical load line is no way to run a power tube, you can't make bass with any power (or the OPT would be the size of a small refrigerator to get the inductance needed). There's a really good reason PP amps supplanted them. I don't want to digress on this, its easy to get me started on the failings of SETs.

I never set out to make the 2nd and 3rd audible (nor do I know any designer who does that with intention) and made our tube amps fully differential in order to cancel even orders throughout the circuit (so tend to produce a dominant H3 rather than H2). I see it sort of the other way around, which is tubes need to go away and to that effect, solid state amp designers need to make their amps 'sound' correct such that tube amp users will abandon the tube amps for something better. Keeping in mind of course that tube amp users tend to own tube amps based on 'sound'.

I think this is happening right now- a lot of the current crop I'm seeing have what I think is the right distortion spectrum, don't have distortion rise with frequency and lower THD so should be greater detail (since distortion obscures detail IME) and just as relaxed as the best tube amps. FWIW, tube users often have complained over the years that solid state amps have more detail but that comes with brightness- so much so they conflate the two! I think you're on the right path when you get both detail and a relaxed presentation at the same time. BTW if you've not seen it, Bruno Putzeys, who had one of the lowest distortion amps ever, just did himself one better! BTW, apparently Bruno thinks the way I do about all this, if we are to take some comments on the Purifi website seriously (note 'harsh sound').

I love your 2nd question! I ask people the same thing- if you can get all the benefits you associate with tubes (greater detail, relaxed, smoother presentation, the ability to listen all day yada yada) in a solid state amp, why do tubes?? They are more expensive, noisier, more heat, less reliability, warm up time (which might take over an hour)...

3rd question: 0.1% is plenty!! 5 or 10% is too much as you lose low level detail- its harder to make out vocals, stuff in the background and so on. All very subjective stuff here of course, but I hear about it all the time.

Short version: "No, I cannot name a bright engineered solid state amp so my assertions can be tested."

 

[atmasphere]

Stuart is not breaking forum rules by being very direct with you. This has been going on for years now, yet it seems we are still where we started. I hope there can be an agreement on terms so we can all be shown that there is more to it. Or not.

When one member attacks another by saying he did something that member did not and identifies those things like 'whining', 'backpedaling', gaslighting, having words twisted around and the like, that falls in the definition of abusive- ask any therapist. On nearly any website abusive behavior is not tolerated 'according to the rules'.

I sent that CD for this project to Stuart a long time ago and other than 'thanks for the CD' nothing came of it. He stopped posting on that particular thread as far as I can make out.

Now I'm being accused of the things I've listed above, I've been gaslighted, my words (as far as I can make out) intentionally misinterpreted and so on.

And you're doing everything you can to avoid demonstrating that your hypothesis is valid.

This sort of thing is saying Stuart knows what is in my head. Its a made up story and its false. Its abusive when I have to defend myself dealing with made up stuff like this.

I have no problem whatsoever with getting to the bottom of this, but I see no reason to take abuse when I ask questions, nor is there any reason for abuse when I state things like why people like tubes (and I've been careful to point out the subjective content but still get taken to task, which is BS). A sticking point was whether Distort could model the behavior I've been talking about, and Paul (the author) admitted that the release version doesn't do that so there's a Beta version now that does. But that's only happened in the last few days and somehow I've been made out to be the bad guy??

So I disagree with your 'not breaking forum rules' assessment. Please have Stuart tone down the snide and just stick to what is actually going on rather than made up stories about me; not having met me he cannot possibly know what's in my head. Thanks.