solid state vs tubes

All of the tech talk aside,what it all boils down to is,you need to have a tube amp at home,in your own system.If possible,it would be nice if you also could have the solid state amp at home available to change between the two, and spend a good amount of time with each.The more time you live with each one,the more of a chance you have to find out what each has to offer.Being in this hobby for several decades, and many different amps,plus other types of components in and out of my system,I find that tube amps do offer a natural sound about them that solid state never has offered me.That aside,I do use solid state also,but mostly for convenience.I am not saying solid state amps are bad.They just can't do the same.People say tubes can't either,mostly in the bass resign.Ever since solid state came out(over fifty years plus ago),they have been trying to give the consumer what they noticed is missing,since their introduction.After all those past years of them (the designers),trying to achieve this,it hasn't changed much,if any.I don't think the tube amp builders are feeling any loss to the serious listener,that has spent a lot a time with both.On the other subject about Bob Carver,that got him taken as being a serious designer in the audio world.He himself stated that the Transfer Function is not going to take place of tubes.He finds that he could be satisfied with solid state.If they did that test at the reviewers home,in their own systems,I imagine the outcome would have been totally different,and would have been more fair.With all of this said,you need to compare the two in your own system,for some time.How long depends on you.I don't think there are any rules in general for the time it may take for someone to notice the plus and minus of each amp type.If they took my amps away,and gave me a choice of one tube amp,or one solid state amp,I think I myself would settle for the tube amp.

Hifi,

Yes, I think each person has their own goals and motivations that determine the right solution for them. Each approach has its own strengths and weaknesses with considerable overlap possible.

In my case, my speakers are the determining factor. My OHM speakers are the key ingredient in my system that cannot be easily replaced by other designs cost effectively. In lieu of using a separate sub perhaps, these speakers require SS amps to get everything they are capable of out of them. That dictates my course. The results satisfy me when I compare them with the best reference systems I have heard, which includes various systems run off tube amps.

So its worth r-iterating again that it is hard to focus on switching just one component (a tube for SS amp) and delivering similar or better results. USually a major change like this will have ripple effects that require other changes to go along with it to achieve the desired results. You should be prepared for that if you make a major change to a system you already like, regardless of teh technologies applied. If you are not ready to potentially have to start all over again, then stay put.

Soft clipping means that dynamic range is restricted to some extent as I understand. That means loudness cues are reduced relatively, all other things aside, as well, right?

What I was talking about is the types of distortions made by tubes and transistors, VS how the ear hears. It is true that the soft clipping of tubes means you will get less of the odd-ordered harmonics, but this has nothing to do with dynamic range. That is a completely different issue!

Minorl, I do take exception to one comment you made about
"well engineered/designed tube or solid state amps", which is the issue of the human ear. If the equipment is "well engineered" to look good on paper, how "well engineered" is it to obey the rules of human hearing? In my book, it is thus not well engineered to the task that it was built for, since the bench specs have very little to do with how human hearing rules.

Have you seen this link? IMO this is one of the more serious stumbling blocks MrT has to face in his quest, and why I commented earlier on the particular SS amps that I did.

http://www.atma-sphere.com/papers/paradigm_paper2.html

"It is true that the soft clipping of tubes means you will get less of the odd-ordered harmonics, but this has nothing to do with dynamic range."

Less loudness cues perhaps then. If you perceive the peaks as less loud because that is how people hear, that would seem to infer that the dynamic range is affected, at least as perceived, since the peaks do not seem as loud anymore, just as those nasty loudness cues due to negative feedback that you are focused on make you perceive things as louder as you describe. Two different things causing perhaps opposite effects in regards to how loudness cues are "perceived"? Only one is adding and one is subtracting. I suppose the truth lies somewhere in the middle then when negative feedback is applied appropriately to not produce the undesired side effects.

Compare the 'best' with the 'best' and see....and not just the amp, but an entire system.
Source, pre/amp and speakers.

I'll bet the BEST of each when properly matched have much more in common than differences. Some of these esoteric differences which I see bandied about, may be unheard in a 'best' system.

Even the best tube amps will fall flat with highly reactive loads of huge impedance swings, while SS has its own limits, maybe when dealing with single driver / full range speakers.

hi magfan:

you make an interesting point regarding differences in sound between "the best of the best" ss and tube amps. i agree with you, but i suspect that such differences will probably be detectable in most cases.

i think it would be interesting for a designer to try to duplicate what bob carver did years ago, when he "fooled" a panel of stereophile's "golden-ears", when he designed a ss amp that could not be distinguished from a cj tube amp by that panel ?

obviously, a particular tube amp would be selected as a bench mark and a ss amp would be designed to sound like the hypothetical tube amp.

can anyone do what bob carver did, again ?

Interesting Mrtennis. It makes me wonder: Do you think there a single set of speakers and components that are capable of revealing everything that the finest examples of each design have to offer?

I suspect, but don't know that the differences between current source and voltage source amps....and the speakers they go BEST with would preclude a single system with 'plug in the amp' testing possible....at the highest level.

As near as I understand it.....Carver nulled the amps by somehow comparing thru a single speaker. When the speaker made NO sound....or some large value 'down', they amps were producing the SAME sound. The louder the speaker, the greater the difference between amps. This is the source of the 't-mod' which was part of my now ancient Carver Cube, the M-400t.

I don't remember the exact numbers, but just for example, when the speaker being used was say......nulled to -60db, you could say they were the 'same' to 1 part in 10,000 or some such.

ONE possible flaw in this ointment is that of the speaker used. If it was a highly reactive load, the tube amp would not be at its 'best' while a speaker of the single driver/full range persuasion may put the SS at a disadvantage. I doubt there is an 'easy' or even 'best' answer here.

Buy / run / listen to, whatever floats your boat. Play safe, eat slowly and chew well. don't stay out late and respect your elders.

LOL Magfan, Just how many shots did you do between those last two paragraphs?

Magfan, You might appreciate this advise:
http://www.youtube.com/watch?v=bpTyG60zvcI&feature=related

This thread is one of those no-win threads.
Like a 'what is best' thread. No single answer.
I'll probably never own a system better than I've got now, unless I win the lottery or somebody tosses me the key and alarm codes to the local fantasy land.
Just trying inject some levity.....the opposite of gravity. It was getting too serious.
And seriously, don't you think I've got a reasonable viewpoint?

Enjoy!

10-05-10. Magfan: As near as I understand it.....Carver nulled the amps by somehow comparing thru a single speaker. When the speaker made NO sound....or some large value 'down', they amps were producing the SAME sound. The louder the speaker, the greater the difference between amps. This is the source of the 't-mod' which was part of my now ancient Carver Cube, the M-400t.

I don't remember the exact numbers, but just for example, when the speaker being used was say......nulled to -60db, you could say they were the 'same' to 1 part in 10,000 or some such.

ONE possible flaw in this ointment is that of the speaker used. If it was a highly reactive load, the tube amp would not be at its 'best' while a speaker of the single driver/full range persuasion may put the SS at a disadvantage. I doubt there is an 'easy' or even 'best' answer here.

You make an excellent point IMO, Magfan. A perfect or near perfect null with one set of speakers, or even a variety of speakers that represent relatively easy loads, would not be meaningful with speakers that are highly reactive, or that have impedance dips that demand more current than the amp's power supply can provide.

As you probably realize, the target amplifier whose transfer function the M400t attempted to duplicate was the Mark Levinson ML2, a pure Class A solid state amp, which although low powered (due to voltage swing limitations) could provide enormous amounts of current into low impedance loads. That effort preceded by a couple of years or so the Stereophile "challenge" where the target was a C-J tube amp, and was performed for and reported by Peter Aczel in "The Audio Critic." That was well before Mr. Aczel's later unfortunate conversion to the belief that all amplifiers meeting certain basic criteria sound the same.

The technique actually involved three speakers. One speaker was connected to amplifier A in the usual manner, except through long cables that allowed the speaker to be placed at an inaudible location. Another identical speaker was connected to amplifier B in a similar manner, and placed at an inaudible location. A third speaker, as well as measuring instruments, were connected between the red terminals of the two amps. It was reported that a 74 db null was achieved, with a variety of music, with the monitor speaker remaining dead silent except for a small ground loop hum. Which is pretty remarkable.

According to a follow-up article in "The Audio Critic" a few years later (Issue 10, in 1987), while the Stereophile challenge initially resulted in a 70db null between the prototype Carver 1.0t and the C-J amp, a later test of that same C-J amp and a production 1.0t resulted in only a 28db null. Unfortunately it wasn't determined if that was because the production 1.0t didn't match the prototype, or because of tube aging or other changes in the C-J, even though Carver had returned the original prototype to Stereophile to enable that determination.

I too used to use an M400t, which I still have although I haven't used it in several years. I found it's sound, with easy to drive speakers, to be quite respectable, but to me far less preferable than the sound of several tube amps I've had. The main differences being that it projected a considerably smaller image (that surprised me, and I have no idea why it would be so), and, not surprisingly, it lacked what I would refer to as the harmonic richness of the tube amps.

Best regards,
-- Al

The m4.0t I had did very well with Magnepan mg1c speakers for years delivering a lot of tube-like attributes in the sound. Most notably, zero fatigue....the longer you listened, the longer you wanted to listen. I cannot go so far as to say the sound was indistinguishable from the tube amp it emulated since I never did that comparison. My perception was it did what it said it did pretty well and I'd leave it at that.

However, it failed miserably when I went to the big OHM 5S3 speakers I currently run. It was a high power 360w/ch amp but had relatively low damping factor and did not deliver much current. Bass was weak. It was never spectacular on the Maggies either, but I attribute that more to the speakers than the amp. The bass on the OHMs is rock solid now with a suitable high curren, high damping amp, the BelCanto ref100m Class D IcePower monoblocks I currently use.

If you perceive the peaks as less loud because that is how people hear, that would seem to infer that the dynamic range is affected, at least as perceived, since the peaks do not seem as loud anymore, just as those nasty loudness cues due to negative feedback that you are focused on make you perceive things as louder as you describe.

Mapman, that is true but is not the same as real dynamic range. I don't think it is a good idea to promote a practice of intentionally distorting the loudness cues in order to make something sound louder than it really is. A lot of amps do that though, and is why they sound loud and shouty, as in: "Turn that !@#$%^ down!!"

IOW, if your system has the ability to sound loud, the loudness cues are being distorted. It is possible to build a stereo that does not seem to play loudly, so that even 105 or 110 db is comfortable. I'm a fan of being able to play the system to life-like levels, that is not possible if it also messes with the loudness cues!

IMO/IME in about 90% of the conversations that audiophiles have about dynamics, the word 'distortion' can safely be substituted without changing the meaning of the conversation. It is the reason I avoid using 'dynamics' except in for this context.

Atmas,

Darn, I thought I submitted you on this topic.

Oh well...

So another way to look at it then is the soft clipping approach distorts the loudness cues by reducing them to make them more digestible to human ears.

OK, but real sound in the real world is what it is. There is nothing there to process the loudness cues in a more digestible manner. Not to say that may not be desirable in an amp.

Distortion and dynamics might be used interchangeably in discussion, but they are clearly two different things albeit often related despite what people might say or think.

Mapman, I agree, the problem is this: distortion, in the form of exaggerated 5th, 7th and 9th harmonics (compared to the original sound) **masquerades** as 'dynamics'.

A simple way to tell that a system is lacking this distortion is that you can't tell how loud it is, until you find that you are shouting to talk to someone sitting right beside you.

Oh, and FWIW, soft clipping does not reduce the loudness cues. Its just more likely to not distort them as much. However clipping in any form is to be avoided, so we are talking about how the loudness cues may or may not get distorted when the system is not clipping at all.

I always chuckle when i here the great tube verses S.S. debate . The choice is simple , as long as you haven't made up your mind on one or the other . Bring home and try as many of both as you can , the one that sounds the best is the one . Its not the means its the results that are important to the true music lovers , I thought we all new that by now . MAX

Tmsorosk, this one was a little different as the OP wants a transistor amp that does what a tube amp does, without the hassle of tubes, if I read things right. There was a discussion of some differences between the technologies that you don't see in the usual debates.

Atmashere Sorry didn't mean to get off topic , it's an audiophile thing . I guess what I was trying to say , do we really want an amp or component thats trying to sound like another technology , or like real music ? MAx

Tmsorosk, I agree we want equipment to sound as much like real unamplified, acoustic instruments as possible (don't think amplified, electronic instruments have a real reference). Now if tubes happen (for arguments sake)to reproduce sound that has properties closer to unamplified, acoustic instruments in a real space compared to SS generally, then an SS that could be indistinguishable from a tube amps in those properties that make tube amps sound better, than I might very well want an SS amp like that, not becuase I care about the technology used, but all things being equal it does seem easier to own an SS amp, even if you have to give up the "joys" of tube rolling to alter the sonic signature of the amp - though even there, I tend to think a tube amp sounds like its circuit design far more than whatever tubes you happen to use. It seems that Nelson Pass, for one, has always tried to make SS amps that can perform like tube amps, which he decided not to make since he felt there were already alot of good tube amps out there and preferred the challenge of making good sounding SS (not that I know him, he sort of says things in his various amp manuals from the Aleph and XA.5 series). They certainly are excellent amps, are they indistinguisable from tube amps? Well, there are alot of Pass/First Watt owners out there that might be able to add their 2 cents on that....

Tvad, I had the Aleph 2,3,J and XA30.5 - I no longer have any of them, but three tube amps; I really did want to have an SS amp, so I tried some of the "best" - but with my speakers.....

Can anybody tell me a pair of speakers that sounds the same well with either tube or SS amplification?

I can think of different speaker/amp combos, some SS and some tube amps, that sound very similar, but I cannot cite a case where a tube and SS amp sounded the same with the same speakers. They will almost always sound different with different resulting sonic strengths and weaknesses, the the listener must decide which is better.

Unless you are Bob Carver and your goal is to emulate one amp with another. I do not know any vendor whose busines is based on that these days. Each quality vendor typically does their thing well, be it SS or tube amps or both. Choice of amp will determine choice of speakers or vice versa.

I think this is the bottom line. Build your system to meet your needs. Use tubes or SS as desired, but do not expect touse either to the same effect with the same speakers.

Harbeth seems to be as fasinable with SS as tubes, whereas my speakers are proabably 98% tube users.

mapman:

i heard avalon ascent and eclipse sound quite good with rowland and audio research ss amps. i've also heard them sound great with tubes.

in my opinion, the issue of ss vs tubes is more critical when the speaker is an electrostatic, ribbon, or planar magnetic.

i have heard vandersteen 2s sound "good" with ss and tube amps.

there are probably other acoustic suspension designs that can perform well with amps of either type.

i have not heard a panel sound as well with a ss amp as with a good tube amp.

i am trying to go cheap and am considering the khartago (odyssey) and vincent hybrid 331. i would like to audition them before buying, if possible.

since both are under $1000, i might take a chance.

MrT.,

yes, no doubt either might sound good with any good speaker design, not just electrostatic.

What I was wondering was do two different amps, much less a SS and a tube amp, ever sound the same. They can sound different and both good in different ways. That's different than sounding "the same".

If any two amps sound the same, then I suspect in most cases the speakers may be the limiting factors. I would expect most high end speakers to not sound the same with two different good amps, even if both were tube or SS, but even more so if one is tube and one is SS.

Unless of course Bob carver or equivalent designed the two to sound the same up front.

So to sum up, bottom line to me is that it is possible to get two amps to sound the same or at least so close the differences are negligible, but this is not likely to be the case in practice, especially if one amp uses tubes and the other transistors.

a hybrid amp--having a tube input stage and ss output stage which is both a tube and solid state amp, has a chance to sound very close to a pure ss or tube amp, by virtue of the ability to alter tube types, may be the answer.

having the versatility of varying tube manufacture could create a more tube like or ss like sound, perhaps creating a sound that is so close to either a pure tube or ss amp, that differences are barely detectable.

mapman, regarding your last point, there was a sss designer, a college professor who designed a ss amp with greater amounts of 2nd and 4th order harmonic distortion, mimicking the sound of a tube amp by creating the pscho acoustic affect of dempahzing treble response. i heard it several years ago at ces. when i can remember the brand name, i will divulge it.

i wrote about this amp, in my review of the ces show at that time.

my point is that like carver, a manufacturer who understands both tube and solid state design and performance could incorporate in a ss amp those features which could create the type of amp i am looking for.

i don't think designers deliberately wish to incorporate coloration, so i will agree that ss and tube amps, will reveal differences , as you have stated which will be recognizable.

personally, i may be willing to accept a solid state amp which can sound pleasant in the treble, yet incorporate greater extension and resolution, so long as it doesn't drive me out of the room. this condition is very subjective.

i would like to keep cost as low as possible and as i indicated would like to audition the odysssey khartago and vincent 331, which is a hybrid amp.

i compliment you on your reasonableness and realistic perspective regarding this issue.

its so basic in audio, that i suspect there is no definitive answer, rather one which one can generate confidence and principles to guide ones personal selection of a particular amp.

i have learned to give up some of my unrealistic desires regarding sound and adopt a more flexible approach.such an approach will allow me to expand my willingness to consider products which i would have not considered years ago.

my stereo system no longer evinces a dark and syrupy sound which i espoused in the past. i have learned to accept a certain level of detail, so long as frequency response is truly balanced.

When considering my latest amp purchase, I strongly considered an ARC SS amp in that I was very impressed with the sound of the sp16 pre-amp and I did not find it to sound overtly "tubey". HAving heard ARC tube gear but not SS, based on what I read doing research, my expectation was that the ARC SS amps would retain the basic house sound which I liked to a good degree. I ended up going Class D instead, mainly foe ergonomic reasons. If the BC refs didn't work out, going with a well received SS amp by a reknowned company like ARC would have likely been my next try. Their SS amp specs certainly indicate that in general they are designed to work with tube pre-amps well.