Tubes v. SS: can you mix and match?


Gentlepeoples - I was under the impression that a tube pre was always mated to a tube amp. Likewise, a SS pre would be mated to a SS amp. Of course, different makes and models of pres and amps could be mated, but I thought tubes should stick with tubes and SS should stick with SS, and never the two should meet. But this doesn't always appear to be the case with some of you. So, when and how are tubes mated with SS? Is it just a question of what sounds good? Are there any parameters at all?
webnick
You bet! Whatever sounds best to you. I'll leave the electrical compatibility issues to someone more competent than me.
Everyone is going to kill me but I believe that tubes can create tone that no solidstate device can achive ever!. Likewise, solidstate can do some things better than tubes. It's a tradeoff. I am totally into the tube sound if the equipment in question is the most musical/emotional available for the price. I think ALL tube cd players and preamps have limitations that do not allow them to reach the pinacle of what is possable today. These two components, with tubes of any kind, have limited dynamics and a loss of leading edge transients that make the music lose energy and to sound soft. This is unaviodable!! and unacceptable if you want all of the music to pass through intact. And I also believe that solid state amps of the non digital kind can not keep up with SET technology ever. This area is the biggest gap in all of audio. Single Ended Triode/no feedback etc. tech. is so far superior to the big SS. monster amps that it is hard to believe when listened to side by side. Digital amps have solved this problem but have only one drawback, TONE. If you can live without the ultimate in tone, then a all solid state system with digital amps or single ended low power solid state amps is the way to go ala the reasoning similar to what 47 labs promotes or placette or Final Labs. If you value tone in the ultimate, then SET amps with solidstate pre and cd are the way to go. I know this is backwards to conventional thinking (most would have a tube cd/pre and solid state amp) but the future is going to change this thinking I believe and an example is Audiopax which has SET amps and Solid state preamp allready! Check out Dr. Gizmo's site for an indepth discussion on why tube pre's are soft. These statements are for the cutting edge best of the best range. AT the other end of the spectrum, in the entry level world, tubes rule!!! Let the flogging begin.
Timo got it right. What ever sounds good to you! Electrically speaking, you would almost have to go out of your way, way out, in order to have Tube and SS electronics be incompatible.
I've been contributing to another thread which has gone in the direction of asking some similar questions. I'm going to snip and post some of my observations from that thread to this one in the hopes that some of the questions I ask may be seen by seen and responded to by more folks. The other thread started about Klipsch speakers. I'm not going to link to that thread as it is pretty long and there'd be much to sift through that is not to the point of this thread.

So here are some of my observations and questions regarding Tubes(+horns) sound as distinctive from SS sound. BTW, as a direct answer to the query of this post: Absolutely you can mix and match the two with excellent results. My reference system combines SET 300B's with Klipsch LaScala (horn loaded speakers). My taste runs along with Mahandave in that I've never heard anything that comes close to that sound (which is, needless to say, pleasing to my ears).

I'll try to snip the following down to just what is pertinent. The fine gentlemen I am referring to at different points are A'goners Bob_bundus and Tubeking:

...... I'm probably on another part of the audiophile spectrum than you and have only a fundamental understanding of the hardware, as well as lacking in ways to describe how it sounds to my ears (not hip to all the lingo, but I sure do know what I like).

I can't answer for Tubeking, but since I have a similar opinions about tubess+horns I can comment on what made me a convert. You will have to forgive my lack of audio-vocabulary to give creadence and color to my statements. The qualities that make tube amplification worth what little extra effort and $ it may take (though I don't know it's been a whole lot in my experience) are about air, atmosphere, soundstage and musicality. While SS has punch and dynamics in spades, bringing those quailities closer to a live performance in the way great SS can just knock the breath out of you sometimes....I do like that aspect of SS. What it lacks though, that the best of tubes, and even some really inexpensive tube rigs can impart, is a depth and airiness...an atmosphere that I've yet to hear SS give to music. There is a holography to the music with great tube amplification that I've never heard with SS. SS had the width, but lacks the depth in my experience (though I must say I was impressed with the Pass Labs Aleph 5 that I had for a short while in that it did have some sense of depth. I've also owned a tube rig that came close to having the 'slam' of SS (a Mesa Baron) but it was certainly at the expense of the atmosphere I get from my 300B SET amps. Ultimately I like the atmosphere over the amazing detail and slam. I was impressed at the detail listening to a good friends Levenson system. Around $50K+, wired well, in an outstanding room with NHT 3.3's (tight bass to write home about). We were listening to a cut on a Beethoven piano concerto disc I'd brought and was familiar with. By god I could hear the pianist feet on the peddles as he played. That was truly amazing. Yet still, bringing that same disk home to the SET amps, though it lacks that kind of crystaline detail (though the ALK's may bring much of that out), I just love the holography that is simply lacking on his rig. Another friend has a $100K Krell setup that raised the hairs on the back of my neck, but the novelty wore off as time went on and the listening session somehow grew tiresome. I never get tired of listening to my SET's and the sound remains engaging to me throughout, though poorly recorder music does become wearing almost immediately. I hope someone else may comment who knows more how to embellish their experience with all the fancy vernacular, or can add a different perspective on it.

That said, I very much doubt you did anything WRONG Bob. And, in fact, there may be nothing you are missing. Even if you listened to the two side by side you may still prefer the sound of SS over tubes. My bias is obviously strongly in the other direction, but I'm always open to hearing a system that will change my mind! I don't think it is a matter of either/or, but I sure love the combination of tubes&horns. For my tastes, I haven't heard better to this day.

Another post:

One thing Tubeking brings to mind in his response that I've been meaning to ask here: Just one more way I like tubes+horns......sitting there in the sweet spot you do get the full holographic effect and enjoyment of what they can bring to musical reproduction. But I also listen to my stereo at times when I'm not sitting in "the spot" (heresy!) and I've never read any posts on this. Perhaps no one wants to fess up....or do you all immediately shut down your system as soon as you leave "the chair"?! With my system obviously the holographic effect is lost once you leave the room. But one of the things I do like most about tubes+horns is that when I leave the room and go cook in the kitchen, or pound away at the keyboard in the office, it still sounds more to me like someone were down in my living room playing the guitar and singing (at best). The SS rigs I've owned and heard in others homes always seem to sound to my ears like there is a stereo playing in the other room once you leave that sweet spot and go off to another spot in the house. I think this can only be a generalization at best for me as my experiences are limited. It could also have a whole lot to do with the structure of the specific home and how the sound travels within that structure(?). But as a generalization it is certainly something I really enjoy about tubes+horns as well, and seems to be consistent in the limited experiences I've had. Can anyone else comment on that?

And still one more:

In an attempt to suggest a clue to the answer to my own question, .....and it may sound like I'm talking out of the side of my mouth here as I fully admit that I'm no sound engineer and the highly scientific and technical aspects of why this stuff works the way it does is as foreign to me as Chinese algebra. I had the pleasure once of visiting and speaking with George Wright of Wright Sound. When I asked him why tubes sound distinctive from SS, the explanation he offered had something to do with exactly how the two reproduced a signal. If you run a signal through a SS amp to an ocilliscope the graph will read as a stair-step hard straight line, rising and falling off like a cliff. Run the same signal through a tube amp and it reads as a curve, rising and falling off more gently. This reminds me of the difference between digital and analog reproduction where the digital represention of the curve of analog becomes a very fine stairstep that represents that curve. The other distinction that I've heard made is that tubes impart certain orders of harmonic distortion that our ears/minds equate more directly with music (or perhaps just as 'pleasing'). To further the description of what I like about tube+horn reproduction of sound that may relate to this: there is something about the way it lets the music just linger in the air and fade off that is very appealing and natural to my ears. SS tends to sound more abrupt and does not have the same sense of "lingering". OK, so enough of my butchering away at scientific (mis)information. Someone who is far more versed in this stuff needs to step in here and set me straight!

Marco
Marco, again I see myself in full agreement with your thinking. In practical terms this means in my case, that in the very complex system which I have built up through the years for myself, I have learnt to prefer all tubes preamps and amps for the midrange, class a solid state for the highs and SS again for the deep bottom end. Cheers,
The main parts of your question have been answered (The first rule is that there are no rules! - I am running SS preamplification with tube power amplification right now), so I'll try to answer your last question. The only real qualification that occasionally arises has to do with impedance mis-matches: Tube preamps *can* have highish output impedances, and SS power amps *can* have lowish input impedances, and the two factors combined *can* roll-off bass response. Axendo said it though - you rarely have to worry about this happening as a practical matter with most gear. One other thing to think about: The well-established existence of 'hybrid' gear, where tube and transistor circuits are combined within a single amplification chassis.
What are the parameters of highish output impedance in tube preamps and lowish input impedances in SS power amps to cause concern?

No real rules of thumb, eh?
I agree that you can do whatever you want. While I have used a tube pre with solid state power and all tube system as well, it occured to me (after many months) that mixing the two can be very nice but, I started wishing I had the best qualities of tubes or the best qualities of SS thru out the amplifier chain. In other words when you mix the two it compromises the best qualities of either, the sound was neither glowing with the sound of tubes or the real direct quality I associate with SS, it was smooth and detailed but missing a little of the magic of either.

Having said the above, I have always wondered what a SS pre and tube power would be like as you would have SS amplifying the lower signals and it would (probably) be quieter than a tube pre and the majority of the amplifying would be done with the tube power amp and you could get the benefits of the tube sound there.

Also what about the posts that mention that SS has only odd harmonics (or is it even?) and tube have only even harmonics? When mixing the two do you get neither or both? I have a hard time believing the even/odd posts, does anyone know of a link that proves this?

Anyway, enough babbling, just have fun :)

i think it also depends on the kind of music you listen to. if you listen to heavy metal only . ss would be better. i think the combo of tubes and ss is a good idea for the audiophile who is on the fence. most audiophiles will eventually prefer tubes i think. the pieces i have heard that would do double duty for the big bucks gryphon has more slam than any ss i have ever heard .it also has midrange like tubes. extention on top like the best ss. if you took my tubes away give me gryphon. tube research gives up nothing to ss in any way. for the person on a budjet the conrad ss amps are awsome as they do vey good double duty as well.
OK, I'll put my unqualified neck on the chopping block...

Webnick: It's the ratios, not the absolute values involved, that matter most. Convention says that there should be a factor of at least 10X between the output impedance of the soucre component (the lower of the two) and the input impedance of the load in order to minimize LF frequency response roll-off (keep in mind that in actuallity, these impedances will vary with frequency, which is usually not specified). Again, the vast majority of preamp/amp combo's will satisfy this criteria. (The other thing that should be watched for if one is using a tube preamp having a highish output impedance, say more than a few hundred ohms, is to avoid long runs of highish-capacitance interconnect, the combination of which can cause premature HF roll-off.)

Philojet: Simplistically speaking, the differences between tubes and transistors that people talk about as far as distortion spectra go has a lot to do with the way they behave when driven into or near clipping (tubes behave more 'nicely', meaning higher overall levels of THD can be less objectionable with tubes). Below clipping, the main differences between distortion spectra have as much to with circuit design as the type of active device(s) used, although tubes will usually display higher overall distortion and noise levels. Simpler tube designs (triodes) are usually considered to display 'nicer' distortion properties than the more powerful tetrodes and pentodes, and a similar characterization is often applied to FET's as compared with bipolar transistors.

As for the distortion spectra themselves, low-order products (mostly the 2nd and 3rd harmonics) are considered less undesirable ('nicer') than higher-order harmonics, a smoothly descending harmonic series (from low-order to high-order) is considered preferable to an unevenly descending/ascending series, and even harmonics tend to be surpressed by typical push/pull amplification circuits (yielding a harmonic series that emphasizes the odd-order products, which by definition are higher-order than the even-order products, and results in an uneven roll-off of the harmonic series). This description ignores a lot of other considerations and types of distortions, including the questions of distortion levels vs. distortion qualities vs. other considerations (such as higher power capability) that may come into play as design trade-offs. (EE's forgive me...)
Wow, that was a mouthful Zaikesman. I didn't understand all of that, I'm sure. Hmm . . . I'm a little long of tooth, now, but I listen to rock a lot, yet enjoy classical on occassion. The speakers are currently Energy A5+2s, but I'm searching for Energy Veritas 2.3s. I want to bail on my faithful SS Adcom 500II preamp and 545II amp, and try a SS preamp/tube amp scenario. No phono here; simple line staging. So passive SS preamp coupled to a tube amp capable of 50 watts and up should do it. I'm looking for a more musical, warmer sound in my Blue Oyster Cult to U2 rock; my reggae's bass will take care of itself. Any thoughts?

Oh, and I'm prety sure my interconnect action is fine. (.5 meter Audioquests)
Webnick, are you sure you meant to say "passive" preamp, not linestage? The two are different (though not mutually exclusive) things. You probably know this, but "linestage" just means there's no phono pre-preamplification included. "Passive" means the inputs and outputs are not actively impedance-buffered and the 'preamp' offers no gain, just attenuation. Going passive *could* offer a theoretical advantage in ultimate transparency under ideal conditions, but there's the rub - it can be very condition-sensitive. I'm guessing that for a relatively non-tweaky audiophile and bass-enthusiast like you seem to be, an active linestage preamp might be the safer bet, especially if you listen at a wide range of volumes.

(My presumptive description of you as a listener and audiophile - if correct - could also point towards SS power amplification over tubes, which generally won't give quite the bass or carefree operation that SS can. This is why many audiophiles who want to incorporate some tubes go the tubed preamp route, but that's another kettle of fish, and as a tube-lover myself I don't want to discourage tubed experimentation. In any case though, you should be able to improve greatly on the Adcom stack, whether you go all-tubed, all-SS, or a combination of the two.)

For your proposed combination of SS preamplification and tubed power amplification, I've found this can work very well, provided of course the gear is up to snuff. In particular, forgoing tubes in the preamp can eliminate some potential hassles with tube noise and finding decent tubes, while I feel that a tubed power amp is the main contributor to providing the greatest traditional strengths of tubes (as well as some weaknesses, but in areas I don't value as highly; I should note that this assessment is probably a minority view). Impedance concerns won't be a factor here: SS preamps (active ones, that is) have low output impedances and tube amps have high input impedances, so the minimum 10X ratio differential rule of thumb will be handily exceeded and no roll-offs will occur. Your options are pretty wide-open, but the way I'd approach it personally would be to get your speakers first, then find an amp that works well with them and your room and tastes, and save the preamp for the crowning touch (well, relatively speaking...next you'll start itching about your source, cables, power... :-)
I'll throw my two cents in the mix, I have a Jolida 1501RC, and have had everything else (SS), well, not everything else (would like to try Pass), but with my Triangles, my current system, is the best I have ever had in 20 years of this obsession, and I am truly pleased..
Hey, Zaikesman. Thanks for your input. Let me address your insights in the order presented.

I thought passive meant 'no tone controls.' Active meant otherwise. My bad. I'm just looking for the cleanest warm sound I can get.

I'm not really a bass enthusiast (even if I seem to be), but rather one who likes sharply defined bass (I don't like it loud, just accurate). So I don't need 'punch' for my music.

So you like the tube amp route? After filing my last post to this thread, I second guessed myself and began to wonder if a tube preamp/ss amp might be a better route. Listeners seem to be dumping a lot of ss amps on the market right now (for example, I've noticed a lot of Adcom 565 monoblocks on the market for relatively cheap). Conversely, seems that the new tube amps on the market in my price range have very low power ratings and the ones that specify the requisite power are older. And as related side questions, do you leave your tube amp on all the time? And is it a relatively new feature that some preamps and have have a power-on standby circuit?

Tunes4me: have you replaced the stock tubes in your Jolida? What did you give for it, if you don't mind me asking, and what did you have before it?

Thanks folks.
Webnick, I think if you consider setting your sights a bit higher (and maybe spending a bit more) than another Adcom - even a more powerful one such as the 565 - you'll be happier in the long run. The speakers you plan to get deserve it. Get the speakers first, then audition some amps, maybe in comparsion to a 565; I don't think you'll be very hard-pressed to find something better. Most audiophiles will allocate at least as much, and often more, to the power amplification than to the speakers. Getting yourself a pair of fairly expensive and revealing speakers, and then trying to power them on the cheap, will rarely work out well - the speakers often wind up highlighting the amp's inadequacies. Listen for yourself and you'll likely agree (and don't neglect trying a speaker cable upgrade at the same time).

You are correct in thinking that you can buy more power for less money going the SS route, although that will not necessarily translate into better sound, or even sound that sounds 'more powerful' - lower-powered tube amps have a habit of exceeding expectations in this area compared to moderately-priced SS amps, so don't get bogged-down in the numbers game of counting rated wpc. Go for quality over quantity.

Bass will usually be more "sharply-defined" with equivalent-quality SS amplification than with tubes. Again, this won't automatically mean 'better' (as in 'more natural') to many listeners, but these things are why you might want to try and hear some tubed amps for yourself before committing, if you can.

To answer your other question, a tubed amp will be turned all the way off when not in use, but it will arrive at fully-warmed-up sooner after being turned on than a SS amp would if it were not on stand-by. Stand-by on preamps is not new, but is more common for SS than for tubes, and running tubes continuously can shorten their life, although so can turning them on and off frequently. Probably most audiophiles turn their tube preamps off when not it use, but there is a large contingent than leaves them on - if you get a tubed pre, you can try this and decide for yourself.
Zaikesman: thanks; very informative. My gut said to wait on a SS amp purchase: I began to wonder if the older SS amp was the way to go. And if I'm buying new, why not go with tubes. I think I'll keep the Adcom around, though. It might be useful in a multi-channel setup powering a subwoofer. What sort of power in a tube amp do you think I need for the Energy Audissey A5+2s? What about tube amp configuration? Pentode, triode? Any particular features I should look for? What manufacturers make entry level 'acceptable quality' tube amps? Thanks for your help, Z.
Webnick, I'm not sure any more what the main thrust of your question is. Listen to some amps of both types if you can. Tube amps aren't made for the mass market, so quality will be at least "acceptable" or better, but sound and quality tend to be pretty comensurate with price until you get above the price range you're likely to be looking in. As for your present speakers, I'm not qualified to offer advice on powering them, but focus on sound quality, not watts. My point is that if you want the better speakers, get a better amp than an old Adcom - be it tube or SS - and I recommend either getting the speakers first or auditioning your amp options through those speakers if you plan on buying them later. The tube options you'll want to look at in your range will not be triode, and basic stereo amps don't have many features to compare. Let your ears be your guide. :-)
I guess I was trying to understand what makes a particular tube amp a quality tube amp. I think I understand now that you were talking in general terms, and that in general, tube amps tend to be of a higher sound quality than SS amps. I'll get to some local shops and start listening to tube amps. Do you have any reservations about three channel tube amps? Do you have any reservations about the Jolida tube amps?
Can't answer for Zaikesman, obviously, but I do have experience with tube gear including Jolida. Jolida do make some great products for the money they charge. Most are built in China as I understand (the company itself is based in MD). The quality is more on the scale of a mass-produced item rather than the more hand-built level that much of the higher-priced tube gear reflects. The Jolida amp I owned was their 302B and was the first tube amp I owned. It was well built but certainly did reflect that distinction I made. If I compare it to the Cary and Quicksilver gear I now use one could certainly tell the difference in quality upon examining both products. I found the Jolida to be immensely enjoyable coming from SS, and would certainly recommend them as a solid introduction to tubes that has pretty good resale value as well, though you may even like it enough to hold onto for a while. You can certainly purchase more refined, hand-built tube products that sound even better still, no doubt about it. You will likely have to add some more $ to your Jolida price tag though, and or buy used gear (which is not necessarily a bad thing). The Jolida 302B I had did yield much of the wonderful qualities tubes have to offer without a huge $ commitment. Eventually it made me yearn for more of what I loved about those qualities. Some of the things that will make the difference in price and quality of tube gear are just how well the amp is designed, the quality of the components used in the amp from capacitors, to transformers to attenuators to tube-sockets to wires and more. Also how well constructed it all is....how much care went into the assembly...is it point-to-point wiring or are printed circuits utilized...are the tranformers hand wound or machine wound and sourced from some other country. As far as three channel amps, I'm not sure if you are asking about Jolida's additional output for a subwoofer(?). I think the use of a subwoofer is a matter of taste. Nothing wrong with it if done right. The Jolida output (subwoofer-out) does not put out much power as I recall so going that route may not give all the punch of going through an separately amplified sub. Perhaps you may be referring to using a center channel, which I have no experience with, but understand it can also be done very effectively. Anyway, hope that input helps.

Marco
Yes, Marco, that does help. And I had been looking at Quicksilver as a matter of fact. Also VTL. Both companies somewhat close to (my SoCal) home. I'm open to older/used equipment but since I know little if nothing about tube amps, I am wary of buying the stuff. The Jolida 1703 is a three channel amp.
Well I'm a big fan of Mike Sanders' Quicksilver gear. Damn fine gear on every level, and the man knows what he is doing. Hand built, point-to-point wiring and overbuilt in every respect. I've owned four different pairs of Quicksilver amps and currently still own two. Love his amps and the one's I've had would all be a step up from the Jolida I owned. Still, for the money the Jolida is hard to beat if you are on a budget. A step up might be Quicksilver Mini-mites paired off with a Quicksilver Line Stage. On the used market that combination can be had for around $1100-1300. With the right speakers you may be very happy with that combination. The music you mentioned that you listen to would be well suited to a push/pull design like the MM's. I don't know how efficient those speakers you mentioned are, but I'd look for something around 92db or more for the MM's. Don't know how big your room is, or how loud you like to listen so you may want to provide that info to get more specific recomendations from others. I don't know VTL so cannot comment. I do recall a friend who had them mentioned his were biased pretty hot so may go through tubes faster and he said that they required hand-picked tubes to run best (I think he said his EL34's were supposed to run at 300ma if I recall correctly). You may want to ask VTL owners about that aspect of it. He did also say that he loved the sound of his VTL's (I think he had the dual mono 100's(?) and was pushing Martin Logan's with them). I never got to hear his rig, so again, cannot comment beyond that.

Marco
The Energy A5+2s are 91db efficient. VTL is a Manley (and son) operation, if I recall.
Webnick, I was not trying to say "...that in general, tube amps tend to be of a higher sound quality than SS amps" - both can have their strengths and weaknesses, and I don't like to generalize sonics as far as 'tube sound' or 'SS sound' types of characterizations. I wasn't clear whether your question was about build quality or sound quality, but all I was trying to say is that tube gear is a specialty product, not made in the hundreds of thousands for general consumption, and will likely have acceptable build quality. My comments about quality being roughly comensurate with increasing price, at least in the sub-several-thousand-$ range, apply to both sound and build (beyond a certain point, you're into luxury cache goods, where all bets are off and image, status, and fetish play equal roles to sound and build quality).

But some brands off especially good value while eschewing fanciness, and VTL and Quicksilver are prominent among them as far as made-in-USA goods go. I can't comment on the current Quickie offerings, but I have heard the VTL ST-85 sounding extremely good with SS preamplification powering 6 1/2"-woofered small floorstanders, so I would certainly give it a listen with the Veritas 2.3's if you're so inclined. (BTW, David Manley hasn't had anything to do with VTL for a number of years, or for that matter the company he founded after he left VTL, Manley Labs. VTL is run by David's son Luke Manley plus Luke's wife Bea, and Manley Labs is run by David's ex-wife EveAnna Manley; David Manley had gone back to Britain or Europe the last I read, and I don't know if he has any industry involvement now. His design concepts do seem to continue to influence both companies to a fair degree, if not always in the same ways.)
I see, thanks. I'll research both VTL and Quicksilver and see if I can audition their stuff. Thanks, again. Whether to tube the pre or the amp or both remains a good question for me. The simple upgrades I've made so far have really improved the sound of the stuff I have now. I appreciate the comments of all of those who have responded.
Why not? It's a good bet that the music you hear has been through many transistor circuits during the recording and disc mastering process, so even if your equipment is tubular you can't attribute its sound to that feature. Maybe it's good for other reasons.
I do know people who have tube amps and SS in the same room. One fellow in particluar has the Mcintosh 2102 tubed amp (100 wass per channel) and he also has the a six channel SS McIntosh amp, for home theater. what is most amazing is the differance in how each of these brnd new amps can sound, in the same room, and wired through the same speakers (only for the sake of comparison). Especially for music listening the 2102 sounds really fantastic. Based on this experience i bought myself a 2102. Anyway, i think this thread has gone the old, well trod route of SS vs tube. I think the qustion was one of routing one through the other. I doubt you can hurt anything.