Tube Amp soundstage

Fairy dust.

Excellent question!  I've made the same observations with many tube amps vs SS over the years, both in my system and in others, and is one of the major reasons I prefer tubes. The soundstage is almost always taller, wider, deeper, and more saturated. Along with this is often a lushness and clarity to the mids and upper mids, as well as air around the treble notes that’s less obvious when I listen to SS. I can’t say as though I know the answer for this definitely, and I certainly don’t mean to turn this into a tube vs SS debate, but I have always suspected that it’s related to higher resolution of the tube amps, which simply reveals more information  and brings us closer to the events of the recording, with both direct and ambient information that contributes to the sense of space.

Well said. If we trace this all the way back to its roots we find at its heart a twisted desire to place what we can measure above what we actually experience. Everyone but everyone actually experiences the superior lifelike depth and quality of tubes. But when we measure them we see the (totally arbitrary) few things we are able to measure seem to measure better even though the amps that measure better wound worse. So we have to go through the 80’s amplifier wars and the 90’s CD and now streaming. All the while anyone with two ears can hear tubes and records beat the pants off digital and solid state.

There’s technical reasons for this but seeing as its technical mumbo jumbo that got us in this fix in the first place you can be darn sure I’m not going down that rabbit hole. No one ever beats a measurebator at tech talk word salad. Learned that lesson long ago.

I will however offer one slightly technical reason. Those of us doing this a while tend to notice simpler is better. Every single tiny little thing affects the signal, and so the more of them there are the more they must be the absolute highest quality. Pop the cover off any two SS and tube amps, the tubes are almost always hands down the simpler circuit with the fewest components. Quality matters more than quantity, and so for any given budget the fewer the parts the more you can afford to spend per part. It really is that simple.

Because I’m a valve person, I have to be honest with you. Well I don’t have to be, but I’m gonna be. :-)

Sweet EL34s, plump KT88, and the all time best 6L6 (I think)

The distortion the valves offer, are the perfect form of chaos when they are done right. The wrong part, that valves ADD, according to a scope, are that "Mojo" you (and I) like.. The imperfect, becomes "Perfect".
I also think that’s why it sounds "THICHER", more of it....

I have heard low watt SS that could get pretty darn close to that perfect, imperfection. A lot of the Pass designs, and their influence on design, put a big smile on my face... The old Adcom, Threshold, First Watt, and Pass. Mark Ls, in a class of their own.. MHO

If I want surgical, clinical , sterile, Krell and a few others come to mind.

Class D, All together different, but they have a good place for me, and my gear...

Regards

The distortion the valves offer, are the perfect form of chaos when they are done right.  

There is a reason for this. Tubes, and analog devices in general, tend to the same even order harmonics that are so prevalent in nature. Everything from violins and drums to tambourines and human voices is chock full of even order harmonics. So when a tube amp adds even a few percent of even order harmonics our brains easily blend it into one seamless whole. 

Solid state and digital however are not at all like this. The distortions they produce are far lower in magnitude, that is true. But we are so much more sensitive to unnatural odd-order harmonics that this seems not to matter. We hear it as more, even while we measure it as less. 

Tubes made the music sound as it should. Christmas tree lights were thread-in incandescent bulbs. The Mistletoe was fresh, as you'd try to be after too much (homemade) eggnog.

+1 oldhvymech

The electrons are free of molecular collisions in the hot glass compared to all that doped silicon so more signal gets through. You could say that the vacuum gives you more air.

Throwing in my two cents: Tubes add harmonic distortions and I believe these distortions cause a slight smearing of the soundstage which gives the illusion of more width, depth and height.

Digital is ones and zeros. 
Analog isn’t. 
Thus the DAC was born to reclaim analog sound. 
Smooth Daddy oh. Smooth. 

I don't consider myself to be an audiophile just a listener that loves music especially hard edged rockin music with a driving bass. Being a guitar enthusiast I knew that most guitar amps used tubes so I was inclined to get a tube amp for my home stereo. This article from an experienced guitar amp technician captures the reasons for using tubes in guitars amps here is a pull quote: 'There are some solid-state circuits that do an impressive job for tone, but the reason guitarists gravitate to tube amps is the harmonics. The secondary harmonics of a tube are additive to the harmony of the note, where the secondary harmonics of a solid-state amplifier are dissident to the tone.' Here is a link to the entire interview which also goes over the differences in the tubes used in many guitar amps: https://www.sweetwater.com/insync/amp-anatomy-power-tubes-affect-tone/
Many of these tubes are the same ones used in home stereos. Hope you enjoy.


 

"Sweet EL34s, plump KT88, and the all time best 6L6 (I think)"

oldhvymec-That's what I hear. Not the modern 6L6, but the lower power RCA 6L6G.

He meant dissonant but I get his drift and he is right, its just what I said above, SS odd order harmonics simply do not sound as good.

@dtapo

now you just need to go down the rabbit hole of SET tube amps and take that tube soundstage, depth, nuance, texture to the next level ;-)

So when a tube amp adds even a few percent of even order harmonics our brains easily blend it into one seamless whole.

Solid state and digital however are not at all like this. The distortions they produce are far lower in magnitude

MC’s assertion that SS amps aren’t mindful to 2nd harmonics is complete rubbish. It’s simply a matter of how the circuit is designed. For decades Nelson Pass has placed a large focus on balancing the right blend of 2nd and 3rd harmonics into his designs, or providing amps with different harmonic flavors to the market. He’s stated in interviews that about 1/3 of listeners prefer 2nd harmonics, 1/3 prefer 3rd, and the rest prefer a blend or have no preference. MC loves to be categorical in the "truths" he pushes but often he is simply asserting a bias.

My bias? Okay, explain to me then how any amp, solid state or otherwise, can be "mindful"?

Okay, explain to me then how any amp, solid state or otherwise, can be "mindful"?

Of course an inanimate object can’t be mindful but the designer of one can be which is my point and you know that regardless of how cute you try to be with your word selection.

You can build your own SS 2nd harmonic generator if you like. Nelson Pass "mindfully" designed it.

http://www.firstwatt.com/pdf/art_h2_v1.pdf

My bias?

And you’re right...it may not have been due to your bias...rather your lack of understanding of SS designs.

Its not a game. You took my perfectly correct post, ran it through your cuisinart and turned it completely around then want to pretend its me. I never said anything about designers being mindful or otherwise. Designers never came up in my post at all. Now you're pretending it did. Crazy. 

What I did say is people prefer 2nd order harmonics. You yourself then argue with this and offer as proof that Nelson Pass himself states that 1/3 of people do indeed prefer 2nd order harmonics. In other words you say I'm wrong while proving me right. Word games, indeed!   

Never anywhere said anything about solid state designs, or designers, only talked about what people prefer, which you just proved I am right about that.  
Could it just maybe possibly be you completely misunderstood everything I said? I genuinely want to know. Because it happens a lot. So either you are a hard one to communicate with, or you are deliberately misleading. Which is it?

MC - you were asserting that tube amps sound better than SS due to their even/2nd harmonics and that SS amps are "not at all like this".  Your words, not mine.  While I agree that tube designs naturally lend themselves to producing 2nd harmonics, so do SS amps if designed that way.  This is not a matter of tube amps categorically producing more even harmonics over SS - it's all about design and implementation.

I'm sure you will enjoy wringing your hands to respond in your usual condescending obtuse way to me so I'm done responding to this thread.  I've made my point.  

Classic MC closing, 

"Holy crap. See how easy that was?  Next question."

Okay so here we go again, only mercifully for the last time. You are now down to admitting, "if designed that way."

Reminding me once again what a good idea it was to create the Hateful 18 list to keep track of which people are worth engaging with and which are not. It doesn't literally mean you are hateful. Although some of them surely are. (And not alone in saying this, I get PM's)
Its easy to pick one of my deliberately provocative comments and get your poor tender feelings all hurt. What a meanie. Boo hoo. What you miss in all this three_easy_payments is you took something I said that was perfectly correct and which you yourself proved you even agree with and then distorted it all to hell in order to call it rubbish.

I do not suffer fools gladly. So sue me. But neither do I deliberately make stuff up (also called LIE) just to insult. That is what you do, and all the time. That is why you made the list. And that is why I promise to do a better job in checking that list and avoiding having anything to do with your distasteful self ever again.  

IMO, Pass has done it right with their SS amps.  As well, Balanced Audio Technology has done it right with their SS amps.  I chose BAT SS amp, a BAT tube preamp, and a Manley tube phono stage and am perfectly pleased with them and that combination.

We buy what we like.  It's all good.  Just enjoy.  Make changes if you wish, there is nothing wrong with that.  No need to argue about it.

Personally, I like it all and enjoy it all.

There are solid state amps that can make a sound stage as good as a tube amp, but most of them are class D.

The differences you hear between tubes and traditional solid state has been about distortion for the last 60 years. Solid state amps have higher ordered harmonic distortion that is more audible than that of tubes, and so tend to be bright. They also can have more distortion at lower power levels, and that can mess with low level detail. But on paper, they appear to have less distortion. But 'less' should be taken with a grain of salt, since the ear reacts differently depending on the kind of distortion being produced.


This stuff is pretty audible; its measurable too but understanding what the measurements mean, and more importantly getting the right measurements is a bit of a trick. One trick that is used commonly in audio is to measure the distortion of the amplifier at 100 Hz. Any solid state amp will measure well at this frequency. But the problem is that such amps have feedback to control distortion, which goes down as frequency increases, because the Gain Bandwidth Product on which the feedback relies is insufficient. So distortion rises with frequency. That is why its measured at 100 Hz, to cover up this problem.

The has been going on for so long that many people, including people that test amplifiers, don't think of it as a problem. But if you measure that amplifier at 3KHz things start to look different- you can see how its distortion is increasing.

So you have two ways to avoid this- either no feedback at all, or so much feedback that the amp is able to compensate for the distortion added due to the operation of the feedback. Feedback does this, if in **insufficient** amounts, through a process called 'bifurcation'. When there's **enough** feedback, this process is suppressed. But that takes north of 35dB, and traditionally to do that at 8-15KHz hasn't really been possible with most of the semiconductors available to designers in past decades. So we still have tubes, which are fairly linear even with no feedback, although they will make more 2nd and/or 3rd harmonic.

The lower ordered harmonics, the 2nd, 3rd and 4th, get treated by the ear the same way- they add a little 'bloom' or 'warmth' (audiophile terms for this) which is relatively innocuous compared to the higher orders, to which the ear is keenly sensitive. If the 2nd or 3rd is present in enough quantity, it will mask the presence of the higher orders and the amp will sound smooth. They also allow you to hear a greater perception of the sound stage- this is the part that most people don't get. The better class D amps have a similar distortion signature (although at a much lower level than tubes, but nevertheless mostly lower orders) and so they can sound quite tube-like (i.e. musical), including the wider deeper soundstage.

The thing is, you might think this to be an error of amps like this, but if you've had the opportunity to hear what the actual musical performance sounded like, you find out that its helpful, because in this way despite the distortion, the sound stage is presented much closer to the original than amps that don't have this property!

tablejockey1,815 posts12-20-2020 8:16am"Sweet EL34s, plump KT88, and the all time best 6L6 (I think)"

oldhvymec-That’s what I hear. Not the modern 6L6, but the lower power RCA 6L6G.

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>

TJ I know the old RCAs will take a heck of a beating, the military metal cover is another tough valve.

Something about a good 6L6, my buddy in Sheldon, great musician, great person. He use to be a BIG time bass player. ALL his bass amps were 6L6. He plays just about anything well, so he starts working on his 6-12 string stuff, again, back to the 6L6. He doesn’t like the British sound, EL34. KT88 are to fat on the bottom, he is tinkering though.. After 55 years of rockin’ he’s not gonna change to much..

I’ll say this though, DON’T buy the cheepos’ (6L6) that are being advertised on EBay from, the Eastern block.. BAD, design and sound. They come out of the box at 10-25% of a new Sylvania, RCA or GE. Just JUNK.. They won’t hold a bias, and take a while to sound OK.. I lost over 10% due to out of the box failure and another 5% with a 24 hour break-in. BAD.

Merry Christmas Everyone.. / Have a Good Holiday..

Regards

MC says "Designers never came up in my post at all. Now you’re pretending it did. Crazy."

Look...the inconvenient truth is that when talking about tubes vs SS You CANNOT separate the equipment from the design if you want to discuss the harmonics that are produced. Period!

Any device, tube or transistor, will display the same basic character with respect to odd or even harmonic distortions depending on how it is used. In a single ended design there is one amplifying device covering the entire musical signal while in a push pull or complimentary design there are two: one for one half of the signal and the other the remaining half. The simple fact that second order harmonics are louder than third order harmonics in most any device dominates the single ended approach while push pull and complimentary designs cancel these distortions by the very nature of their operation. What this means is that any device, tube or transistor, will display the same basic character with respect to odd or even harmonic distortions depending on how it is used.

MC makes these erroneous claims about even harmonics being attributable to the tubes themselves...and SS gear (w/o any design considerations) produces more odd harmonics. This is just plain wrong regardless of how MC chooses to spin it. It’s not about a tube vs a transistor - it’s all about implementation...yes, the friggin’ design!

From a practical standpoint most SS designs are not single-ended and lend themselves to producing odd harmonics so MC falls into the trap of believing it must be due to the gear using SS components instead of valves. Wrong. So very wrong. This isn’t word play MC, this isn’t a game, this isn’t dastardly use of a Cusinart...this is just you not understanding something.

The Sylvania 6L6 is very nice indeed.

Ralph post is a Phd,

of course SS with a tube front end SS output , liquid cooling, no emiter resistors, etc and a few other tricks can sound incredible, see Vandersteen M5, M7
of course soundstage depends on preserving those subtle time and phase related cues as well as not burying them in whatever flavor of distortion you may prefer.... lots of feedback kills image depth, easy test with an SPL meter, genius ( mindful designer ) Roger Modjeski designed RM-9 with variable feedback :-) ears are required

@dtapo
You may have already answered your own question, comparing first hand. Trust your ears. Maybe there is some magic in the distortion and 2nd and 3rd order harmonics.   

Gotta ask oneself why many of the high-end class A solid state designers and amp builders continue to try and build circuits and test various output transistor types to try and make their amps sound like valve tube amps. Getting closer, not fully 3D or as layered yet.   

Ralph’s post is perfect to demonstrate how the design and implementation are applied to get the desired outcome from an amp. Designers of both tubes and transistors make choices and tradeoffs to achieve their goals. Tubes have a relatively high output impedance and are not easily capable of driving a loudspeaker directly – where the opposite is true for transistors. This is why most tube power amplifiers have large output transformers and transistor amplifiers do not. The transformer addresses the tube output issue but certainly has sonic drawbacks. This is why a number of Ralph’s designs "fix" this problem by creating output transformerless amplifiers. It’s all about the implementation.

lots of feedback kills image depth, easy test with an SPL meter, genius ( mindful designer ) Roger Modjeski designed RM-9 with variable feedback :-) ears are required

A bit of a correction here- feedback, properly implemented, does not kill image depth. **Improperly** implemented feedback does that and other things (brightness, harshness) as well.


For feedback to really do its job, it needs to be really a lot. Like over 35dB or so. Less than that and you have those problems above. One thing about sound stage BTW- to do it right you need zero phase shift in the audio band. This is why in our tube amps we've had 2Hz to 200KHz bandwidth, since you need to go 1/10x or 10x the cutoff frequency to prevent phase shift components in the passband - in this case the audio band of 20Hz to 20KHz.

But you can get around this with a class D implementation, since you can apply a lot of feedback with class D- so much that the amp goes into oscillation. The trick is to use the oscillation as the switching frequency. Then the amp might only have good bandwidth to 20KHz, but it can have so much feedback that its able to correct for phase shift that might otherwise be present on account of the filter at the output of the amp. Class D distortion is caused by errors in the the encoding and by something called 'dead time' (topic for another thread) but both tend to cause lower ordered harmonics. Because of this, a class D amp with a lot of feedback can have as much depth and stage width as a tube amplifier.

"I wondering if someone could explain to me the reason my tube amp has a deeper soundstage than my SS amps?"

Maybe the SS amps just aren't designed that way. I have a ML 335 that has as much if not more soundstage than any KT88, EL34, etc based amps I've owned. But then again maybe the tube amps I've had were not designed that way.

I don't have the tools (a brain) to quantify why the OP's statement seems mostly true. But I let my ears accept what I hear even though I don't know the hows or whys. The measurement folks just reject everything as being in our heads and don't care about what they hear. 

The reason why i bought 2 integrated from Sansui ,one of the top one in the AU series (7700) and one of the Alpha series(a601) was their tubelike quality in imaging and their flowing organic non analytic but detailed S.Q.

Sansui takes a seriously S.S. amplifier versus tubes amplifiers.... They designed the 2 types...

Sansui go on for almost 50 years in audio and the goal for their last 30 years was reproducing their best tube amplifier sound (1965) in a solid state version(1995), they accomplish that after more than 30 years of continuous research... Name one company in audio that have the same goal for 30 years ? Not an indefinite improvement goal, nor a general one, but a very difficult task and precise one, finally accomplished just before their bankrupcy..... reproducing in S.S. their best tube amplifier sound....Read that review... this is astounding...






«Sansui has been a company that improves its products step by step. The early Sansui transistor amps, such as AU-999, AU-9500, AU-9900, AU-919, and AU-D11 all sounded like trying to be like tube amps, and never got there. Sansui stated to change that from AU-D11II, AU-G99X, and AU-X701(this was AU-Alpha607 in Japan (1988)). The high frequency of AU-X701 is so sensitive that Sansui has succeed to go to the root of tube technology; however, they were definitely weak in low compared with tube amps– this is nothing more than comparison, I still like the sound of AU-G99X and AU-X701 much better compared with todayÂ’s expensive transistor amps.

By knowing this Sansui tradition, the astonishing resemblance in sound between 907MR and AU-111 tells me that Sansui might have been designing its amps to reach the ultimate sonic submit they have already reached thirty years ago. Even, they might have been using AU-111 as a reference amp for their goal – I can ask those questions to those Japanese engineers whom Mr. Motoki has introduced to me.

This suspicion also coincides with what Sansui did. As I said, Sansui has been a company that always tried to improve the product by one step at a time. The last high-end integrated amp Sansui ever produced was AU-111G in 2000. This was AU-111 specifically redesigned on the pre-amp section for SACD and DVD Audio use. By considering the Sansui tradition, if AU-111G had not sounded equal or better than AU-Alpha907NRA, they would not have introduced AU-111G. This thought process and the result of my test also tell me that Sansui finally archived its goal before it ceased to exist in high-end audio market; to produce the ultimate transistor amp that is equal to the best tube amp Sansui ever produced.»

http://www.sansui.us/issues_AU111vsAL907MR.htm


If i "upgrade" my 2 Sansui that give me a ratio quality/price over the roof, one of the choice i had without risking deception, will be the ZOTL technology of Berning design.... A completely new tube technology without any negative reviews...
Like for my Sansui go on the net and try to look for a negative review....Good luck.... 😁😊


For answer to the OP question, my Sansui S.S. give me a soundstage filling the room and an imaging totally differentiated with a natural instrument timbe BUT in a controlled mechanical, electrical, and acoustical embeddings...

Without these embeddings controls the Sansui is not so spectacular even if this is a very good S.S. design...

Then it needs ac embeddings controls to make you amplifier reach his optimal......Then tube or S.S. is not the true question.... The embeddings are....

Merry Christmas...

Independently from theory (which is of course interesting by itself) I was (and  continue) comparing the soundstage of Stingray tube integrated amplifier (in push-pull) and  Cherry Megascino class D that I use with Wyred4sound STP2 preamplifier. Stingray (with EL84) in push pull gives a wonderful soundstage. Although  I cannot complain about the soundstage in the SS settingas neither. I would say the tubes  give more echo like soundstage (which I personally love)  whereas the Cherry gives reasonably natural soundstage which is further expanded by the STP preamp. I can feel the " body " of each instrument in all three dimensions without an echo-effect (perhaps, because of a very low THD). 
Given that with class D you can also hear more details (especially in mid-high frequencies), the sound is more clear and natural (nothing to say about non-auditionable benefits of class D), perhaps I like more my SS setting (thought again I love my tube integrated). 

Marry Christmas

niodari thanks your post illustrate the difficulties to reach an absolute conclusion...

The reason is simple the tube gear and the S.S. gear in the same room will not react in the same positive or detrimental manner in all the aspect of the S.Q. delivered in THIS room...

Mechanical, electrical, and acoustical embeddings of an audio system works marvel but not in the same way on 2 audio systems... IIt is particularly evident in the case of 2 different speakers but it work the same for different audio system...

This is the reason why my embeddings controls, mechanical, electrical, and mainly acoustical are installed by my ears for my actual audio system....

If there is no or minimal embeddings controls in your room this will work the same, no 2 different system feel and work the same way in an environment, in particular the acoustical one....

MC likes to twist what he said to drive his point or dispute someone. He can change his words as he goes, post to post, thread to thread. Never two alike.
He also likes to twist what others say, but we won’t go there now.
Whatever is convenient at the time. Got to keep that post count up higher than anyone.