Tube vs Solid State Is the War

[Gregadd]

Tom

it's not tubes it's not solid state, they can both "sound" exactly the same, that is significant

The point is not to get them to sound like each other, but to sound like music. I never claimed that tubes performed "magic." I started this thread to suggest maybe we had reached the point where both are equally capable of that goal. Or ,as you put it, we are properly executing the theory.

 

[MylesBAstor]

Tom

The point is not to get them to sound like each other, but to sound like music.

Bingo!

 

[microstrip]

OK, but lets be sure what we think we got a hold of!

I see that this test proved that there was no magic involved in tubes nor solid state, and that by manipulating phase, frequency and distortion they both sounded so similar to esteemed audiophiles that they could not tell the difference................again, it proved that tubes or solid state, neither one is magical, it IS all in the execution and circuitry.

Please don't overlook this.....between solid state and tubes, there is no MAGIC, only execution (and goes without saying expectation bias and preference and blah
blah..

Tom

Tom,
Well, do you have any scientific prove that Bob Carver was no magician?

Anyway, I repeat myself - the tests were not documented. You say "by manipulating phase, frequency and distortion" - who can assure you that this was the only thing that was manipulated it these modifications? That non-linear modifications were not carried? What are the magnitudes of these manipulations?

An experiment can only be considered documented if we have all the information needed to repeat it and check the results independently. Repeatability and consistency of results is a key issue in this discussion. Why until today no other designer of transistor amplifiers has managed to repeat the trick? Should we believe that Bob Carver was the only magician?

Surely execution is the key word in sound type - I can guess that sooner or later someone will be even able to emulate a tube amplifier using high computing power and ultra HIREZ hardware. But as far as I know not today.

What is magic today can be real tomorrow. But for today it is still magic!

 

[Ron Party]

Why until today no other designer of transistor amplifiers has managed to repeat the trick?

And you know this how?

 

[mep]

So it's not the size of the wiggle that counts ey?

No not class D, all transistors switch, at least that's how I understand it. As far as the sensitivity studies go, the cone like "composite" construction of the inner ear (as opposed to Tim's outer ear hair ) hair cells suggest that while the frequency might not register in the brain sound pressure does. In other words we are much more sensitive to minute changes in volume than previously thought. If this is the case, then MY guess is, the cumulative effect of these zero crossings could be the root of the SS "grainy character" cliche. Come to think of it, SS designers have actually been trying smooth the transition since the beginning. Companies like Spectral, Soulution and Lamm have attacked it by switching faster, companies like Pass Labs by going into fewer output devices with heavy class A bias. ML is dealing with it by interleaving. In the past it was done mainly with an intelligent bias system. Edge has it's own proprietary biasing scheme. Think about it for a minute. The dig against SS is that it does not have the "flow" of tubes. This is something I agree with even if I am using SS output stage amps that are already fast switching AND are biased fully in Class A. The study stated in passing that 24 or 30 frames per second might be enough to fool the eyes but the ear evolved to detect over 20,000 frames per second so they, in some instances, could be harder to fool. Interesting stuff. Where the heck is that study? I will try and find it again.

If we look at things from the zero crossing point perspective the same problem appears to be the very same as a digital vs analog debate or Hi-Rez vs Redbook debate even. Orb already mentioned the time domain, I think he's right.

From what little I know, transistors are switches that turn off and on depending on how they are biased just as tubes switch on and off when used in a push pull circuit (conducting/non-conducting). The crossover distortion occurs when one half of the output stages “hands off” to the other side. In pure Class A, the output devices whether SS or tubes never stop conducting, but there is still a “hand off” to the other side of the output circuit (push or pull).

Only single-ended amplifiers amplify both halves of the waveform and the penalty with tube single-ended circuits is normally low power, high heat, and added second harmonic distortion because of the lack of cancellation of harmonics you see in push-pull circuits not to mention saturation of the output transformer due to the magnetic gap. It’s all a tradeoff no matter the technology.

 

[Ron Party]

...and, for that matter, should we also ask the corollary? Has any designer of a tube amp managed to perform this *trick*, i.e., to make his/her tube amp sound like a SS amp such that it is indistinguishable in a blind test?

 

[fas42]

No not class D, all transistors switch, at least that's how I understand it. As far as the sensitivity studies go, the cone like "composite" construction of the inner ear (as opposed to Tim's outer ear hair ) hair cells suggest that while the frequency might not register in the brain sound pressure does. In other words we are much more sensitive to minute changes in volume than previously thought. If this is the case, then MY guess is, the cumulative effect of these zero crossings could be the root of the SS "grainy character" cliche. Come to think of it, SS designers have actually been trying smooth the transition since the beginning. Companies like Spectral, Soulution and Lamm have attacked it by switching faster, companies like Pass Labs by going into fewer output devices with heavy class A bias. ML is dealing with it by interleaving. In the past it was done mainly with an intelligent bias system. Edge has it's own proprietary biasing scheme. Think about it for a minute. The dig against SS is that it does not have the "flow" of tubes. This is something I agree with even if I am using SS output stage amps that are already fast switching AND are biased fully in Class A. The study stated in passing that 24 or 30 frames per second might be enough to fool the eyes but the ear evolved to detect over 20,000 frames per second so they, in some instances, could be harder to fool. Interesting stuff. Where the heck is that study? I will try and find it again.

Yes, most output stages have some level of passing through a switch off zone, unless pure class A, like SET. But it's not so much the crossover that's the problem, but rather that the power supplies have to deliver nasty current waveforms to the devices to make it happen correctly. That's why I emphasise the need to get that area right, because it's the voltages fumbling the ball here that mucks up the sound. So as a simple further explanation of why tubes sound "better", it's because their supplies don't have to spit big and sharp wads of current into the circuit to make it work cleanly, they use voltage to do the heavy lifting.

Frank

 

[mauidan]

...and, for that matter, should we also ask the corollary? Has any designer of a tube amp managed to perform this *trick*, i.e., to make his/her tube amp sound like a SS amp such that it is indistinguishable in a blind test?

Why would any tube amp designer want to perform this trick?

 

[Orb]

Thanks for the link, it was good reading.

Orb, while I agree there is energy above our abilty to hear in instruments, these energies occur as sinewaveish ( I make a careful but technical distinction from a pure sinewave as extracted from the movement of a circle...wikpedia has info on that), but again, the waves, all of them are damn near a sinewave. Air does not conduct square waves or triangular waves or any other stuff. This has to be understood, and thus I am not partially wrong on this matter of sinewaves (sinewavish...they are not perfect circle waves but so very very close). Think of air like water, if it helps...a push immediatly entows a pull so to speak. Even if you smack water with a big flat stick, it does not project out with a repeating square wave form. Its nature and all that jazz. Now, making a square wave out of an infinite number of sinewaves is good math stuff. But, folks can get confused about electronics easily, especially when it comes to filters, who generate sinewaves at the frequency they are excited at, even if they are excited by pulses and not sinewaves, its the old push the swing thing.

Tom

Yeah I agree all sounds can be broken down into individual sinewaves we agree
But I will say a complex note relies upon many combined sinewaves to create it and so changes it to something much more than circle waves even allowing for approximation/close-ish look, I think we are debating the difference between sinewaves and complex waveforms and here is where our perspectives differ on what is sound and how it looks.
If looking at the frequency snapshot from that earlier link you can see even from 20hz to 20kz it is an incredibly complex waveform when considering the partials-harmonics.
Harmonics must be considered because these are what help to define timbre,etc, on top of this critically the time domain is essential to how we perceive the said instrument's waveform (better to say envelope) as modern research has pointed to attack stage of an instruments sound being critical to our perception, while also the sustain-decay affect other aspects relating to the instrument-note.

As in the example link I gave that showed a complex waveform of a note played on a trumpet, how would you explain that as being a sinewave when it does not repeat in the same way as those?
Furthermore looking at both in the time domain and also the partials-harmonics the differences are massive due to a sinewave being periodic.
They can only look similar once the complex waveform is broken down using Fourier analysis, and what we end up with is many individual sinewaves that must be combined to give us that complex waveform.
Look at the very last graph on this link that shows an envelop-spectral decay of what I am mentioning about the complexity of a musical note and its harmonics;
http://www.sfu.ca/sonic-studio/handbook/Fourier_Analysis.html
Then compare that for a simple tone-sinewave.

One of the best summary articles out there is that by Bill Buxton (who JJ knew at Microsoft), and maybe Amir.
He covers aspects from simple tone-sinewaves to complex waveform, and importance of the time domain-envelope, along with other fundamental aspects.
Acoustics and Psychoacoustics:
http://www.billbuxton.com/AudioUI02acoustics.pdf

Just throwing it out there for those who are interested in an easy to read summary on the subject.
Cheers
Orb

 

[microstrip]

And you know this how?

Oh, I see I forget to add AFAIK before the sentence (and any other in this particular debate, as we are discussing poorly documented facts - I only read the magazine reports). If you know otherwise please educate us.

 

[microstrip]

...and, for that matter, should we also ask the corollary? Has any designer of a tube amp managed to perform this *trick*, i.e., to make his/her tube amp sound like a SS amp such that it is indistinguishable in a blind test?

The following remark is subjective and was not proved by any blind test, but I have found that many excellent tube amplifiers during the first few minutes of warm-up sound like what I would tipically call solid state sound.
BTW, we are centring our debate in power amplifiers, but I have found that similar arguments apply to tube preamplifiers, where we have no interaction between the output stage and the loudspeaker.

 

[Phelonious Ponk]

Why until today no other designer of transistor amplifiers has managed to repeat the trick?

The answer to that is simple: There's no market for it. Those who believe in the superiority of tubes have never accepted the success of the Carver challenge, and the last thing those who believe in the superiority of SS want is an SS amp made to sound like tubes. In this age, you could probably create a SS amp with digital modeling circuitry in it to emulate the sound of Lamm, Conrad Johnson, etc, and a few of the more famous SS amps (though they'd all sound enough alike that it wouldn't be much of a challenge). But the people who even know what Lamm, Conrad Johnson, etc, is wouldn't believe in the concept and wouldn't buy the product. Why do you think the guy who made a relatively inexpensive SS amp sound like an esoteric tube amp is now building tubes?

He wants to sell some amps.

Tim

 

[MylesBAstor]

Why would any tube amp designer want to perform this trick?

I've heard it done inadvertantly Never asked them what they did since was running out of the room as fast as possible

 

[MylesBAstor]

Yes, most output stages have some level of passing through a switch off zone, unless pure class A, like SET. But it's not so much the crossover that's the problem, but rather that the power supplies have to deliver nasty current waveforms to the devices to make it happen correctly. That's why I emphasise the need to get that area right, because it's the voltages fumbling the ball here that mucks up the sound. So as a simple further explanation of why tubes sound "better", it's because their supplies don't have to spit big and sharp wads of current into the circuit to make it work cleanly, they use voltage to do the heavy lifting.

Frank

If I'm reading you correctly, you're talking about transistor crossover notch distortion? If so, that's nothing new and been known about for what, a couple of decades? And in that time, solid-state designers haven't figured out a solution?

 

[JackD201]

From what little I know, transistors are switches that turn off and on depending on how they are biased just as tubes switch on and off when used in a push pull circuit (conducting/non-conducting). The crossover distortion occurs when one half of the output stages “hands off” to the other side. In pure Class A, the output devices whether SS or tubes never stop conducting, but there is still a “hand off” to the other side of the output circuit (push or pull).

Only single-ended amplifiers amplify both halves of the waveform and the penalty with tube single-ended circuits is normally low power, high heat, and added second harmonic distortion because of the lack of cancellation of harmonics you see in push-pull circuits not to mention saturation of the output transformer due to the magnetic gap. It’s all a tradeoff no matter the technology.

That is exactly how I also understand it

 

[MylesBAstor]

The answer to that is simple: There's no market for it. Those who believe in the superiority of tubes have never accepted the success of the Carver challenge, and the last thing those who believe in the superiority of SS want is an SS amp made to sound like tubes. In this age, you could probably create a SS amp with digital modeling circuitry in it to emulate the sound of Lamm, Conrad Johnson, etc, and a few of the more famous SS amps (though they'd all sound enough alike that it wouldn't be much of a challenge). But the people who even know what Lamm, Conrad Johnson, etc, is wouldn't believe in the concept and wouldn't buy the product. Why do you think the guy who made a relatively inexpensive SS amp sound like an esoteric tube amp is now building tubes?

He wants to sell some amps.

Tim

That line of reasoning is so fallacious as to be absurd. That's the same arguments presented as to why analog/vinyl lovers didn't like the sound of digital. Oh, people with LPs had a vested interest, blah, blah, blah. Yeah, well maybe a few souls but the vast majority of the audiophiles I know don't give a rats ass about the technology, only that the equipment (software medium) sounds good. And if were for the audiophiles, digital wouldn't have caught on; it was John and Jane Q. Public who adopted digital, and not because it sounded better, but it was more convenient, could be played in a car or boom box or a discman and they could man/woman handle the disc and it would in general play. Plus they took up less storage space.

 

[Phelonious Ponk]

If I'm reading you correctly, you're talking about transistor crossover notch distortion? If so, that's nothing new and been known about for what, a couple of decades? And in that time, solid-state designers haven't figured out a solution?

Myles, that's because a couple of decades of engineers haven't "emphasized the right area" to prevent the voltages from "fumbling the ball" and "mucking up the sound." If they'd just get those "big sharp wads" under control the "heavy lifting" would take care of itself and it would all be on song. Sorry you were having trouble following the engineer talk.

Tim

 

[Phelonious Ponk]

That line of reasoning is so fallacious as to be absurd. That's the same arguments presented as to why analog/vinyl lovers didn't like the sound of digital. Oh, people with LPs had a vested interest, blah, blah, blah. Yeah, well maybe a few souls but the vast majority of the audiophiles I know don't give a rats ass about the technology, only that the equipment (software medium) sounds good. And if were for the audiophiles, digital wouldn't have caught on; it was John and Jane Q. Public who adopted digital, and not because it sounded better, but it was more convenient, could be played in a car or boom box or a discman and they could man/woman handle the disc and it would in general play. Plus they took up less storage space.

John and Jane Q Public have always driven the market, Myles, and it has always been driven by convenience. Convenience is exactly what vinyl was all about. But none of that changes the fact that there is no audiophile market for solid state amplifiers built to sound like tube amplifiers. They are two separate camps, as is illustrated by this thread and a thousand like it. Is it absurd to believe those camps won't cross over in significant numbers because someone can build tubes that sound like SS or SS that sounds like tubes? I think it would be naive to believe anything else. But your mileage, of course, may vary.

Tim

 

[Gregadd]

Tim every field of endeavor needs a guy like Carver to shake things up.

Audiophiles and reviewers deal with finished product. If anybody failed to deal with the Carver challenge it was audio manufacturers. Reviewers can only review finished product. Audiophiles can only buy what is offered for sale I'm not aware of any white paper detailing with what Carver did. As far as I know the actual details of what Carver did was proprietary.

If anybody failed to deal adequately with the Carver challenge it was Carver.

BTW I did not consider what Carver did a trick. When I heard the amp it was just a nice amp. It certainly did not sound an all out design like the Carver Silver Seven.

 

[Gregadd]

But none of that changes the fact that there is no audiophile market for solid state amplifiers built to sound like tube amplifiers.

The term "tube like" is a common term. One of the highest honors bestowed upon a solid state device. Hybrid is an attempt to marry the virtues of both camps.