solid state vs tubes

Atmasphere; I owned the ZERO gold ic and sp's. They were ok. I was never really thrilled with them. You spend that kind of $'s, even second hand, you should be ecstatic. I never noticed the improvement you speak of. I am not saying it did not exsist. They are very well made, as they should be, but very very stiff. Tough to install and feel comfortable with their instalation. Of couarse this is all secondary. It is the preformance that matters the most. Getting back to what I believe the original point of this post, SS and Tube. No simple answer, but prior to my exsisting system I had Krell evo 202 and Evo 600's. I still had the Zero's which were only change recently. The krell which I had for 2yrs were shipped the day before the Vtl arrived. So not side by side but pretty close. Many of the attributes are very close. Bottom end, mids and high's very simalar. The main differance to me is bloom. A wider sound with a slightly differant(deeper wider) stage. I will say the biggest change from any replacement of equipment in my 2 channel anolog setup was the cartridge(the source). An immediate(instant) change. In my case for the BETTER! The largest bang for the buck. At least in my system. Of course, it was the last change as well, so that may have something to do with it. But much more noticable then cables, amps or pre-amp at this level anyway. Having said that, I love my tub set up, down sides and all.

Rtn,

The problem with that is a lot of audio other than clearly audible distortion or noise, most of the rest is subjective. Otherwise, in the end, the owners opinion is really all that matters.

Of course its still always possible to discuss what one hears civilly in that almost everyone still has something that they can learn.

I think in the next 3 to 5 years Class D gear will over take tube gear (Sound Wise)

Dev,

There is a profound lack of criticism in audio, which is even more extra-ordinary considering the prices. I will not comment on Spectron, not having heard it, and not having an interest in hearing it.

Of course, your perception is not valid because of issues related to burn-in, cabling, speaker matching, component matching, music selection, or speaker positioning. Take your pick. And even if you went through all these items, in your own home, for every piece in the world and decided you didn't like it... Still, someone, somewhere, in some system might find it heavenly. Ergo, any piece of audio, once constructed, is infallible.

I wish people would come out sometimes and say, "It sucks". That would make this hobby much more simple.

Spectron or better mono's?

I finally heard these (mono's with all options) in another members system paired up with Analysis Audio Amphitryon panels who has been raving about his sound for a while now in other threads so I was very anxious to hear, well I did and I did not think much of the set-up, I actuatly felt sorry for the guy. Now before the bullets start flying it could have been something else within the chain but it was very disappointing and I couldn't find anything to comment positive on. A good friend went over to this members place at another time because he really wanted to hear these Greek speakers as they have been raved about and having a conversations afterwards also had nothing positive to say except he felt it could not be due to the speakers themselves but someting else farther up the chain.

How do you tell someone who is so convinced their system is all that when by far it isn't?

MrT, I have one word for you...Spectron! Or even better for your planars two words...mono Spectrons!

"i will repeat, i am not looking for tube-like per se, but rather to be unable to detect the difference between a ss and tube amp, driving a pair of planar speakers."

I don't think anybody can tell what you will or will not be able to detect. Only you know what you hear and like.

All I can add and then I'll check out is that good sound is good sound, regardless of the technology used to achieve it. And only you know what good sound means to you. So don't be hung up on it must sound like this technology or that. Just do your homework, try some good SS amps and hear for yourself. If you really want to ditch the tube amps bad enough, I am certain you will. Otherwise just live with the tubes for better and for worse.

Unsound the zeros have a 60 day trial period so you can try them on your own system with no risk.

LOL, Atmasphere, I've got hand it to you, you do know what you like. The Ridley runs hot and hardly increases power much at all into lower impedances. Just like yours.

MrT, there was a time when planars ruled the roost when it comes to resolution. That time has passed- there are a good number of cone systems now that easily compete with the best planars.

However, my comments were more the point that if you had a 16 ohm planar, any amp that you have tried so far would sound better on such a speaker.

IMO, one of the most musical transistor amps that is also reasonably priced are the zero-feedback Pass amplifiers, particularly the First-Watt amps. The Ayre is another good choice. So far the best I have heard, better than most tube amps, is the Ridley Audio amplifier. Beyond that, most transistor amps that employ large amounts of feedback are going to sound a lot more like each other than they will like anything else, including tubes.

I should point out though that the 3 amps I listed also are known for making heat, as the simple fact of the matter is that class A operation is part of how these amps manage to sound right. In fact, the Ridley employs a heater to raise and regulate the heat of the output devices. So other than occasional tube replacement, IMO you might as well have a tube amp, if quality sound like real music is your goal...

i will repeat, i am not looking for tube-like per se, but rather to be unable to detect the difference between a ss and tube amp, driving a pair of planar speakers.

i might be able to find a ss amp which exhibits tube like characteristics, yet it may also exhibit ss aspects. that is not my goal.

i'll give a crude analogy.

suppose i have an apple. i like to find another fruit that tastes like an apple that is not an apple.

from what i have read so far it is virtually impossible.

Dev,

In your case those mbls would pretty much dictate SS amplification.

BTW you are a lucky guy. Nothing does 3-d imaging of large scale classical recordings as holographically as the larger mbls I have heard.

Interesting read with lots of opinions but there is more to it than just the amp and in the end just that opinions and really no right or wrong.

That being said I replaced my CAT JL3 Sig. MKII mono blocks $40K with the new Bryston Squared 28's less than half the list price and I'm very pleased, I have not found any other amps no matter what price and/or design and I have had allot of world class pces making me want to change, my speakers are MBL 101E's. I'm after getting the most out of my speakers.

I know of others whom have been trying these amps and have been pleasently surprised also so you might want to try. My preference is haveing solid state paired up with a tube pre, I'm currently using a VAC Sig. MK2a and truely enjoying.

Another member said this;

09-26-10: Bryceeboy

The first time I ever got what the SET group was raving about was when I inserted the 28B Squared into my system. I am a tube guy through and through but when I placed these in my system nothing had come close in the past. I own Soundlab A-1's which are a bear to drive but these things can make them growl or purr like a kitty. Great amps IMHO! Good luck.

Atmasphere, silly me, I forgot about the Macs. I was referring to the Pass M2.

Mr T.

That's fine I think you need to state the question as might your speakers sound tube like with a ss amp. Nothing else really matters if that is what you seek.

I personally think it is possible with some SS amps, maybe even the better Class Ds. You might want to through some tube gear up front in the pre-amp or source in order to keep things leaning more towards the pure tube sound, but I'd be willing to bet you can do it with a SS pre-amp and maybe no tubes at all.

I would not hesitate to suggest trying the Carver m4.0t that I used with mg1cs for years with no real tubes. A used one would only cost a few hundred. Or maybe even a m1.0T which is the amp that was voiced to sound like the CJ reference amp. My only reservation with this combo was that a sub was needed for the low end to be competitive with truly top notch systems in that regard.

hi mapman:

the issue of discerning the difference between a tube amp and a ss amp, ceteris paribus, is of great interest to me.

if i can be foooled or cannot tell the difference between a ss or tube amp as party of a stereo system, why have the tube amp.

ralph: i thinki the issue is planar vs cones , not impedance.

it may be harder to tell the difference between amps using cones, than panels, regardless of a con designs impedance curve.

in my case , a planar owner, i think it is easy to tell the difference between ss and tube amp. electrostats and ribbons do not have the same impedance curve, yet they are -panels.

i have heard rowland and avalon sound very pleasant , when combined, but i have yet to hear a panel speaker with a class d or ss amp drive an electrostat or ribbon, or planar magnetic exhibit a well beheaved upper midrange, treble response.

i realize it is preference and i expect that finding a ss amp that will be livable is almost impossible. i have no illusions, but will not give up the quest, as yet.

Unsound, in this case Mr. Norber was telling me, as did the other manufacturers, that indeed their amps do sound better into higher impedances, despite making less power.

The Mac autoformers are used to load the transistors at a lower impedance if I recall right, quite the opposite of what we are talking about. I have to tell you, I was quite surprised to find that the ZEROs have a benefit to transistor amps in the same way that they do for tubes, although when it was pointed out that this has to do with the behavior of the output devices when more current is put through them, it makes perfect sense.

With regards to speaker cables, it appears to be simple DC resistance.

Atmasphere, auto-formers aren't a new concept. The only ss amplifier I know of that includes an auto-former appears to do so in an effort to adapt to an otherwise speaker mismatch. If auto-formers were of such benefit and without deficits, why wouldn't they be included in all original amp designs? Or if not amps, why not original speaker designs? Of course we don't listen to amps, but speakers powered by amps. That para-phrased statement of Mr. Norbert is quite a bit different than claiming that ss amp sounds better into higher impedance loads.
What aspect of the speaker cable is this attributed to?

Unsound, Paul Speltz who makes the ZEROs has a letter from Steve McCormick, in which Steve asserts that his amps, which have no problem with 4 ohms at all, sound better driving 4 ohms through the ZEROs.

Upon hearing about this (which was about 2 years ago) the next time I was at CES I asked about this subject with several of my friends in the industry who make transistor amps. I was surprised that there was a consensus amongst them, that I can paraphrase (this one stated almost verbatim from Edge's Steven Norber) 'just because it is comfortable driving four ohms does not mean it is sounding its best', this specifically in relation to 16 ohms.

One thing that you may not be considering is the role of the speaker cables, which is critical with 4 ohms but not so at 16 ohms. For example if you do the math, you find that no matter how high the damping factor of the amp, there are no speaker cables that will allow the amp to express anything more than 250 into 4 ohms.

In short, in high end audio there is no compelling case for 4 ohms. Its bad for tubes, bad for transistors. How this might relate to MrT's inquiry is that his job would be easier were he to use a higher impedance speaker.

BTW, I do concede that in my comments 'all other things being equal' is a serious caveat. They never are. Because of that, it took a long time to figure out how important this issue actually is.

Finally, I would like to point out to MrT an issue that must be considered: speakers that are designed to work with transistors may not work with tubes, and vice versa. This is an old conversation, that of equipment matching, but touches on a larger subject:

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

So many possible responses.
Isn't it true that when connecting to the various taps on a transformer that you are using more or fewer windings? Won't that change sound more than the load variations to a SS amp?
I like the talk of sensitivity and efficiency as different things. Also on the plate is impedance...and not just a single nominal number, but the range, along with min / max for any given speaker.
Than again, nobody has yet mentioned phase. I am told that Harbeth makes LS 3/5a type speakers and though they are about 83db sensitive, make a wonderful match for tube amps. Benign phase and moderate impedance range are key.
My panels should work with tubes, as well. Reasonably flat impedance curve and no wacky phase problems.

Naw, I think the concept at least is pretty simple. Compatibility / synergy can be chosen electrically. Magic happens when you get it REALLY right. It shouldn't take a lot of money for a good, basic, solid, good sounding simple system. No need to spend a bundle on cables, either.

Again, damping has come up. And nobody has mentioned speaker 'Q'. What role does the design of the speaker have in all this? Can't a critically damped speaker produce fine bass in an 0 damping factor system? I suspect so.
You don't need a DF of 10,000 to get good bass 'control', which is one of the red herrings of audio. A speaker with 'Q'=1.25 will be sloppy almost no matter WHAT you do.

"The break down rate on the tubes was only slightly higher retubing for my preamp was $ 550. per year , my power amp $2200. per year"

Wow, that's scary.

The tubes in my ARC sp16 are coming up on 2 years with a lot of play. I have had minor noise issues that I have alleviated by shuffling existing tubes, but I think the time is coming to replace all. From ARC, the cost of doing that is about $30 a tube or $180 dollars total for 6 12AX7s.

I really like the ARC but if I were shelling out hundreds a year just to retain the good sound, it would probably be out the door and back to all SS for me.

I have had many tube and solid state components , I've slowly gone all S.S. . The last 3 to 4 years tube and solid state has nearly reached convergance , at least in the higher end . The break down rate on the tubes was only slightly higher retubing for my preamp was $ 550. per year , my power amp $2200. per year , the odd time you would get a bad tube and have to start over . Go over your recommended tube life and things would start to go very wrong , so I was listing less to save tube life , also the heat from the tubes in the summer meant reduced listing time . I loved my tubes , but I have found S.S. gear thats equally as injoyable , although somewhat more pricy up front . M

Mapman, One of the advantages of ss amplification is it's inherently low output impedance, low speaker impedance speaker loads are almost never a concern. There are some, that believe that the best results occur when impedance's are more closely matched (Jeff Roland?) rather than having a low to high ratio. I suspect it might have more to do with application. It appears to me that it is much easier to achieve better bass response and steadier impedance loads in lower impedance speakers than in higher impedance speakers.

MrT:

That was not your original question.

Which is it?

my original question has not been answered:

has anyone participated in a "blind" test comparing a solid state amp to a tube amp and been unable to discern the difference between them , say 7 out of 10 times ?

Maybe.

In general, I believe higher ratios of input impedance on a device downstream to output impedance of the device upstream to always be a good thing, all other things aside.

Of course, in reality you can't just conveniently focus on on e factor and push all others aside, so who knows in any particular case. No one ingredient alone makes for good soup.

Mapman, I am not convinced that a higher impedance is a technically better playing field. In fact I believe the opposite to be true.

Unsound,

I think speakers are generally voiced to sound a particular way with certain kinds of amps and vice versa. I suspect tweaking the impedance load in any given case would change the sound and present a better opportunity for the right amp to now deliver better sound. I doubt that in practice though this would always necessarily be the end result. Its all about amp/speaker synergy which can be achieved via many combos, warts and all. Providing a technically better playing field as a higher impedance likely does does not necessarily assure better results.

Mapman, I suspect that in narrow technical terms there might be something to it, but I wonder if it would hold up in broader technical terms. More importantly, I agree with you, that in practice it might not matter.

I think Atmasphere's assertion regarding higher ohm speakers is one of those things that is probably accurate in a technical sense but in practice does not always determine what will sound best to an individual.

Still, I do think there is something to it and would love to do the test if there were a way to do it cost effectively and with no risk up front in case it does not pan out for me.

Atmasphere, you have still not convinced me that your opinion is a fact. That I have always preferred systems that have amplification driving loads under 8 Ohms to those with amplifiers driving loads over 8 Ohms, leaves me to doubt these assertions. In the end, the final sound is what counts, and at least to my ears, that holds true regardless of whether one uses sensitivity or efficiency as an amplification guide line.

Atmas,

Assuming providing 16 ohm loads is not more costly, which seems to make sense to me, where can I buy or try the tweak that does it inexpensively without dropping big bucks on something fancy like the zeros up front?

An inexpensive solution would seem like a natural thing for a company like yours to offer in order to enable your amps to drive a larger assortment of common speaker designs better?

Aren't 4 ohm loads more problematic for tube amps in general? Isn't that part of teh [sic] reason why you advocate 8 ohm or higher speakers for use with your tube amps?

This is true. The fact of the matter is that **all** amplifier technologies sound better (better= smoother, greater detail, often more authority, and in tubes less lower-ordered distortions that contribute to the 'tube sound') when driving higher impedances. IME 8 ohms is OK (better than 4) but where the 'magic' happens is with 16 ohms.

So I usually put it this way: If *sound quality* is your goal, 16 ohms will sound better than 4 or 8 ohms, all other things being equal. If **sound pressure** is your goal, then 4 ohms (or possibly less) is preferred if you have a transistor amp that can handle the load.

The point is that in high end audio, we are more concerned about getting it to sound real rather than anything else. Quite often (as in Unsound's case per his last post), things might be sounding *good enough* so that one is satisfied, but that is rarely the same as saying that the sound is as good as it could be. Its whether one is interested in making that step in the interest of better sound. I say this because quite often a speaker design could be a 16 ohm design or 8, rather than 4, without seriously altering the design. It does not have to be more expensive. Its really up to the speaker manufacturers, but I think most of them don't want to raise the impedance because they fear loss of 'voltage sensitivity'.

Have you noticed that there is speaker efficiency, 1 watt/1 meter, and there is also sensitivity, 2.83 volts/1 meter? The fact of the matter is 16 ohm speakers might be less sensitive, but they will not be less efficient. If this seems hard to get your brain around, consider the idea that the sensitivity spec was created to cover for the fact that many speakers are not as efficient as they are made out to be.

Wolf,

I'm largely with you in regards to my view of tube and SS amps.

Class D is a godsend for getting the most cost effectively out of most recordings in particular modern ones which can tend to be more challenging due to loudness levels applied with modern speakers that tend to be less efficient and are often difficult to drive to the max properly.

I've found Class D is like one of the last missing pieces I needed for getting good sound all the time out of my system.

I think many who complain about the sound quality of modern digital recordings need to get with the times and give Class D a try perhaps. Or continue to just live in the past and complain about anything that is new or different.

I want the best of both worlds. Class D helps more people achieve that.

Just ask any (experienced) guitar player. ALL amps sound different, as well they should. I think the bottom line is that tube stereo amps sound better than ever but they're fussy, relatively expensive (relative to SS designs), and tubes start to kill themselves off pretty quick. I love the harmonic richness and appropriate tactile response tubes give to my various guitar amps (when biased correctly and using good tubes), but SS hifi amps (well designed ones) can, of course, sound amazingly musical and they seem to keep sounding that way much longer than tube amps with less upkeep. I prefer MOSFETs (warmer or something), and I am gonna try a class "d" hifi amp soon (modern pro audio is all about class "d"...those "phased array" speakers you heard at that concert with your girlfriend on your shoulders spilling beer on your head...likely class "d" powered).

In my youth there was a definite difference in sound between tubes and solid state. Audio Research and Conrad Johnson vs. Krell and Mark Levenson. Today, the very best designs have closed the gap so that there isn't a solid state or tube sound. There are excellent examples of each. Today,Audio Research and Ayre sound more similar than different.

aTMAS,

Aren't 4 ohm loads more problematic for tube amps in general? Isn't that part of teh reason why you advocate 8 ohm or higher speakers for use with your tube amps?

I will gladly try the zeros if someone wants to loan me a pair. If I ever experiment with a SET amp down the road, the zeros might come in handy.

Atmasphere, until I see more compelling evidence, or get a free trial, I'm not spending my hard earned money on something like this. I don't hear the need.

Hello Unsound, you can see the issue in the curves of most semiconductors, perhaps easier when you compare input capacitance to current.

At any rate, its easy enough to hear! Get a set of ZEROs and a 4 ohm speaker, listen to the difference when driving direct or though the ZEROs.

Mapman,
http://www.conrad-johnson.com/It_just_sounds_right/a-pr4.html

Mapman, yes, as the footnote confirms it was a conrad-johnson Premier Four.

Unsound,

Yes, I recall that. It was a CJ amp that the Carver m1.0t was emulating I think?

I had a Carver m4.0t with silver seven transfer function to sound like Carver's statement tube amp for years. It did sound more like a tube amp than most SS amps perhaps and put out 360 w/ch to boot. It worked very well with Magnepan mg1cs, conveying a lot of typical tube amp strengths and weaknesses.

The devices made by IR are 100% not symmetrical MOSFETs. The gate and source are on the top of the device, while the drain is the bottom of the wafer, which, while I can't discuss fabrication details, has an ohmic contact with the package.

So, gate/source is very low cap while the drain is many microns away, so should have much higher capacitance.

No effort at all for a groove-type symmetry. This is strictly a planar device.

Rleff (nice, diffusion oriented name).....I'm not knowledgable about probe enough to know who makes what. The last HP stuff I saw in a test area were the frequency meters used to tune quartz crystal oscillators. This was no later than about '80.

Mapman, you might find this interesting:
http://www.stereophile.com/features/the_carver_challenge/index.html

From what I have read about the line, my impression is that CJ gear is not a line that can be emulated practically by SS in that it has a distinctive signature and less neutral tube sound. My impression of VTl is similar but perhaps not to the same extent.

as i have stated before, my favorite amp is the conrad johnson mv 125. i am convinced that there does not exists a solid state amp that comes close to the cj.

i don't own the cj. i own a pair of vtl deluxe 120s.

based upon the comments so far , i am confident that i will not find a solid state amp which sounds like the vtls. that is , i would expect that in a blind test, i think i could identify the difference between my vtls and any ss amp.

thus, all i can do is listen to some more ss amps until i throw my hands in the air and give up.

i suspect i should look for class a amps for likely candidates.

incidentally, i once owned a pass aleph 0 and was using it with a pair of quad 63s.

i did not like the treble response and sold the amp.

Magfan the hp4062ux is a parametric tester used with probers to test wafers when they come out of the fab.

Atmasphere, how is this "non-linearity" measured, and at what level does it become an issue?

Magfan, here's a nice nutshell explanation that touches on this subject.

That there are capacitive elements of semiconductors should not come as a surprise to anyone- most tuners these days do not rely on variable capacitors to tune the station, instead they use variactor diodes, which take advantage of this capacitive element. Literally by changing the voltage (and thus forward current) on the device the capacitance changes and is useful as a tuning cap in the RF front end of the tuner.

Here's the link for the MOSFET capacitances (you can find many others on this site):

http://www.diyaudio.com/forums/tubes-valves/155106-ss-followers-drive-power-tubes-3.html#post2316318