Why Tube Amps Sound Different (and better) Than SS Amps

[Orb]

The other thing worth noting. Carver said his amp was nulling -39 db. One would expect that might be audible. And as JGH said, 4 out of 5 is not significant. Suppose he was just one less. 3 of 5 or one the other way 4 of 5. Many complain when this sort of objection is brought up. One can use the random number function in a spreadsheet to see how often 4 of 5 happens. I just did and in 100 trials, which done 5 at a time is 20 runs, it occurred 5 times that 4 of 5 at random turned up. That is one in four by chance. Suggestive, but simply not enough to be conclusive.

Hence why I mention nothing can be concluded either way in the discussion apart from the engineering and this goes beyond distortion/FR, and that it is very easy to go in unprepared for blind listening
Even JGH states the listening test would need more results to be conclusive, however worth remembering the initial listening (where seemed there were no differences between amps) and the follow up were casual sighted, eventually they went to blind test selection to provide greater validation that unfortunately run out of time with just 5 tests.

Most would use the Clark rule that would need 11-12/15 correct, however even this is way too simplistic because outside of AES other JND research use a sliding scale regarding %; the basis being as something becomes smaller it may still be noticable but accuracy will be much lower in dbt.
I posted several scientific papers or parts from ones I have 1-2 years ago relating to a broad spectrum and diverse range of JND, including biases-determination-weighting-etc, but it is something I am not bothered about doing again as it takes an insane amount of time to ensure context,validation and use is correct.

Anyway worth remembering that initially they (JGH and JA) did not notice differences and was only over time; whether this was because the amp tolerances-spec-performance due to the nature of its build were compromised or the fact greater length of time listening enabled a more methodical approach in terms of music-sounds used that then focused on emphasised traits we cannot say.
However key aspect is JGH mentioning using specific segment music-trait to "engineer" differentiation.

Not disagreeing btw.
Cheers
Orb

 

[Ethan Winer]

In this you are wrong, operating out of ideas over 40 years old. What you don't seem to understand is ...

I was extremely clear in my explanation. All you have is "you're wrong" which is not compelling. Please read what I wrote again, and maybe it will make sense to you. If it doesn't, please cite my specific points individually, and hopefully we'll come to an understanding about what is audible and what is not and why. Here it is again for your convenience:

What you miss is that the magnitude of distortion matters much more than its specific makeup. Nobody will hear 0.01 percent distortion whether it's mostly odd or mostly even, and even budget amplifiers often achieve distortion that low. Further, the notion that odd-order harmonics are more objectionable is simply false. It depends on the context, and how far away (in frequency) the added harmonics are compared to the fundamental due to the masking effect. A clarinet produces mostly odd overtones, so adding a 2nd harmonic will change its timbre more noticeably than adding a 3rd harmonic which is already present anyway. Further, even or odd THD is much less important than IM distortion, which is vastly more objectionable than any THD. Since THD and IMD are always present together, IMD is the most irritating type of distortion.

Next you wrote:

We can hear odd ordered harmonic content that is so low as to be unmeasurable.

No we can't, and this shows a fundamental misunderstanding of how we hear and what can be measured. Now, I'm always glad to change my mind, but you'll have to prove it by posting an audio example file or similar evidence. I'm also curious where you got that from, and why you believe it's true. Can you cite a legitimate scientific reference?

IMD is quite audible, but Don here seems to have the better grasp:

What Don said does not disagree with what I said.

--Ethan

 

[Ethan Winer]

If you have a sound editor like SoundForge, you can use the synthesis generator to produce a fundamental and up to three harmonics at the same time.

Yes! I suggest this all the time to people who don't understand how to relate dB or percentage distortion amounts to what can be heard.

Even order harmonics are hardest to detect. In fact, up to 3% THD may go unnoticed on simple waveforms. But if the harmonic is not an even-order multiple of the fundamental, harmonics can be detected at low as 1% THD.

Yes again. In extreme cases such as a fundamental plus only a very high-order harmonic, it can be detected at an even lower level. I can hear a 3 KHz sine wave 60 dB below a 100 Hz tone. But the notion that anyone can hear 0.001 percent distortion is pure fantasy, especially when you consider that loudspeakers typically add 100 to 10,000 times more distortion!

--Ethan

 

[Phelonious Ponk]

OK, maybe i'm being too cynical guys. Bob Carver has made a $700 chip amp sound like a high-end tube amp. He can do that. So you tell me...why is he building this:



Tim

 

[DaveyF]

OK, maybe i'm being too cynical guys. Bob Carver has made a $700 chip amp sound like a high-end tube amp. He can do that. So you tell me...why is he building this:

View attachment 13881

Tim

My guess would be he's gone into partnership with the tube manufacturing company.

 

[esldude]

Infinity must have done something different in later models as the EMIMs/EMITs in the RS1bs and Betas were 4 ohm.

Well I think they called them 4 ohm, but of course a single number is not a good description of loudspeaker impedance as I am sure you know.

http://www.stereophile.com/content/infinity-irs-beta-loudspeaker-measurements

Here are some measurements of the Beta. Notice how the range covered by ENIMS and EMITs is a roller coaster between just below 2 ohms and 6 ohms. Several up and down peaks between a 1 khz and 10 khz. An amp like the VTL is going have its frequency response altered a noticeable amount vs. a Threshold that likely would not be effected to any significant degree. If for no other reason than the impedance interaction those amps will sound different.

 

[esldude]

OK, maybe i'm being too cynical guys. Bob Carver has made a $700 chip amp sound like a high-end tube amp. He can do that. So you tell me...why is he building this:


Tim

Yes, and in regards to his old motivation, whether honest or not, he said he made the original Silver Seven to create the ultimate tube amp. Which he then copied in his SS mainstream amps. He agreed to sell Silver Sevens at what I believe he considered a price so high not many would be asked for. And probably made more than he imagined. The Silver Seven was simply a reference for his other amps to shoot for according to him.

So why is he making this now? Like I said, I believe he was surprised at how many Silver Seven's sold. So going back into it now, sure this is what he is drawn to. Maybe he just wants a statement product people will remember and talk about. He knows even in his serious SS work like the Lightstar, it won't garner attention like the amp pictured above. Maybe it is a fraud, maybe it is cynical, maybe he just at this point wants the attention.

One would think replicating the sound of what some thought the SOTA amp of its time for $700 would have gotten enough note. Even if he was in need of hand building such copies seems it would have gotten him kudos. It didn't. That is not a lesson that escaped his notice.

 

[mep]

Tim-Two things to keep in mind:

1.The amp that you posted a picture of is the one that Bob is giving a 20 year warranty on the output tubes which is simply unheard of.
2. At this stage of Bob's career, he can do any damn thing he wants to. The fact that he wants to design and manufacture vacuum tube amps is telling.

Maybe, just maybe, Bob wants to leave a legacy of building some of the finest tube amps that have ever been made. No one who has been involved in audio for any length of time doubts the brilliance of Bob Carver. Bob was the first engineer to bring high watt SS amps to market with his Phase Linear company. I still have a pair of the Phase Linear 400 Series 2 amps and I wouldn't be embarrassed to play them for anyone. Bob then went on to form two other successful companies under the Carver and Sunfire names. With the exception of the original Silver 7 amps, Bob made his reputation with building innovative SS gear. Again, he may want to leave another mark on the audio world by designing and building world-class tube amps. More power to him.

 

[treitz3]

Mark, if you have ever had the chance to hear one of the smaller tube amps he recently designed.....you may be right. The one I heard below bested a VTL tube amplifier and not by a small margin either.

Tom

 

[Gregadd]

Imitation is the sincerest form of flattery. This thread is about tubes besting solid state. So far we cited his ube amps and tube clones. Can someone remind me of his his solid state designs ?

 

[treitz3]

Hello, Greg. I take it you are referring to Carver. Yeah, they do not sound like his tube amps. Even within the same lineup, the SS amps do not sound the same.

Tom

 

[esldude]

Imitation is the sincerest form of flattery. This thread is about tubes besting solid state. So far we cited his ube amps and tube clones. Can someone remind me of his his solid state designs ?

Unless you are simply posting in jest, I guess he was first noted for his Phase Linear designs. Skipping the in between, the last and greatest of his designs in solid state was probably the Carver Lightstar, and the very similar Sunfire amp.

 

[thedudeabides]

Imitation is the sincerest form of flattery. This thread is about tubes besting solid state. So far we cited his ube amps and tube clones. Can someone remind me of his his solid state designs ?

Hi Gregadd,

With all due respect, can you make your posts a bit more "coherent"?

The grammar hurts my ears.

GG

 

[Whatmore]

Mark, you and I are hung up on the same statement:
it is unheard of, but has anybody seen his warranty in writing? Signal level tubes, I know last for 10 years running around the clock 24X375 and who knows how long after that...but power tubes lasting 20 years...that would be a game changer for many and i do not think there is any circuit in his amp that can extend the life of a filament/cathode but he is a magic audio designer...but.....naaaw. maybe he is getting special tubes....

It's here in black and white under the heading "warranty"

 

[Gregadd]

Hello, Greg. I take it you are referring to Carver. Yeah, they do not sound like his tube amps. Even within the same lineup, the SS amps do not sound the same.

Tom

Hello Tom. I think my thinly veiled suggestion is that Carver is a tube guy. Using him as an advocate
for the superiority of solid state is probably a mistake.

 

[Gregadd]

Hi Gregadd,

With all due respect, can you make your posts a bit more "coherent"?

The grammar hurts my ears.

GG

thanks for asking. I can always do better. There is a reason. But it is my own private business

 

[thedudeabides]

Greg,

My bad. Sincere apologies. Your input is always appreciated.

Best,

GG

 

[Gregadd]

Apology is accepted. I am happy to expand on any point you could not comprehend.

 

[thedudeabides]

I must admit that I learn so much from you and others who have a much better background on the technical side and other related aspects of music reproduction than I.

GG

 

[esldude]

Hello Tom. I think my thinly veiled suggestion is that Carver is a tube guy. Using him as an advocate
for the superiority of solid state is probably a mistake.

'

Well see if we get past personality and preference whether someone is a tube guy or not is of no consequence. One is of superior fidelity to the input or they both equally are. We know they generally as manufactured aren't of equal fidelity.

Tim deParavicini has said he can get identical sound from tubes or SS. When asked why he used tubes he said that is where the market is. People will pay more for and pay more attention to tubes than an identical sounding SS unit. I suspect Bob Carver has found the same. The visual impression that you have something special in his Super Silver Seven is beyond that of a solid state unit. The heft, weight, all the glowing tubes is not something that seems as substantial in transistor form.

BTW, Mr. Carver worked with Mr. deParavicini on his current design. Mr. deParavicini desinged the input and driver stages, they collaborated on how do to the feedback while Mr. Carver handled the output stage and power supply.