What do you see as the downside of tubes?

Unsound, taking your word that your not hitting the pipe, you may want to re-read your first post alongside the most recent post. The comparison may be revelatory and theraputic(just like good tube amps).

I haven't found a "downside" to tubes. My love for the sound of the real thing, and the frequency at which I get to hear it, demands that I get as close to it as possible at home. Ditto the cost of the best NOS tubes. My view of their cost is directly related to my love of music. Further: Tube rolling is an inexpensive/easy way for a person to give the sound of his/her system a gentle nudge in a particular direction. A flexible, purely subjective method of adjustment available, relative to the listener's tastes. Regardless of what aural preferences one may have: rolling a couple tubes can take one from merely, "OK" to Audio Nirvana. Try that with your SS system.

About tube-rolling, I was always a fan of NOS tubes and am now having second thoughts. I was using xf1 Mullard EL34s as driver tubes in my SET monoblocks and tried some of the reissue Genalex/Gold Lion KT77s instead and was floored at the improvement. Since the KT77s, while not exactly cheap, are MUCH less costly than the Mullards, it was definitely a win-win. Dave

Krauti:

You cannot run a tube amp 24/7 because the output tubes pass a lot of current and will wear out too quickly. This is generally not the case with gear like tube preamps or tubed DAC's that use small-signal tubes (little tubes) - 24/7 operation with small-signal tubes usually extends life and yields better sound, as turning gear on and off subjects the tubes to harmful thermal cycles, as well as a voltage rush on power up if the gear uses solid-state rectification, which is most gear. The latter factor is the biggest problem, which is another advantage of tube rectification and why a lot of tube preamps have a "soft-start" feature which applies voltage slowly to the tube filaments on power-up.

And as others have noted, a tube amp with a lot of output tubes will heat up a room (extreme cases, like ARC's 600 series reference amps, basically require a separate room or custom air conditioning unless you are running them in a gigantic room).

I have a solid-state amp (darTZeel) and tube amp (VAC Renaissance 70/70) in my living room, and run the solid-state amp most of the time because, like the poster who spawned your question, I like the convenience of being able to listen whenever I want. The VAC sounds good in 10 minutes, but sounds better after a few hours of operation, and I don't like powering up the amp and exposing it to a thermal cycle when I'm only going to listen for a few minutes. I do run the VAC in the spring and summer when there are frequent electrical storms, as I work far from home and am not able to get home to power down the darTZeel during electrical storms.

Just to be clear, the issue with tube amps and 24/7 operation is that the big output tubes pass a lot of current, even while idling, and this creates undue wear. Small signal-tubes, on the other hand, pass very little current in most circuits, and as I have written ad nauseum in other threads on this forum, when left on 24/7, they tend to either die within 200-250 hours from "infant mortality" (defective manufacture), or they basically last forever.

Maineiac, in my first post on this thread, I answered the Krauti's question. In my subsequent posts, I replied to the responses to my posts. "Revelatory, theraputic (just like a good tube amp).)"? Perhaps stepping way from the tubes for a while might offer you some perspective. It's not as though I am insensitive to many of the charms of tubes. I have yet to hear any speakers that do better with tubes that I care to own.

Good point Raquel. While I sometimes keep my preamp and CD player powered up for days at a time, my hybrid amps get powered down at night or whenever I do not expect to be listening for most of the day. I would expect it to be a good idea to power down fully tubed amps for the reasons you state.

As the original poster of this thread I actually like the fact that this thread has taken on it's own life. Think that's just what happens over time as once the downsides I've asked for have been stated thread drift sets in.

That some folks seem to find it necessary to ask what others may be "on" isn't what I had intended, but then again, I have no power over this thread and shouldn't. But hey, this is where that proverbial grain of salt may be helpful.

Raquel, thanks for a clear answer as to why tube amps shouldn't be run 24/7.

Well, it's a long weekend and as there's more to life than audio gear and so I shall try to catch a fish and check back later on the life this thread has taken on. In a way I agree that it has outlived it's usefullness as my questions have been answered and my decision is still the same. Hiho, hiho, and off to tubes I go, hiho hiho, hiho hiho......

Enjoy the long weekend
As far as how many times the same thing needs to repeated I think once or twice is good enough.

Loose bass, forward midrange, bright glassy upper mids/lower highs, rolled off upper highs. Variable performance. Unreliable. High maintance. Difficult to get replacement parts. When they break, they offer the potential to break other links in the system. Excessive heat. Potential burns to children, pets and others. Can cause fires. Requires more care in placement. Limited to use with high impedance speakers. High cost per Watt. Greater sensitivity to speaker cables. Sensitive to vibrations.

Why all the fuss - most of this is quite true although it is a matter of degree. Perhaps Unsound paints an overly negative description for sure, but if you asked people to make a general list of all the cons against tubes they would probably come up with at least four or five items from Unsound's even longer list.

Of course there are a great many pros for tubes starting with their sweet organic, harmonically rich, engaging and musical sound but the OP didn't ask for that.

Dopogue- I had always used Phillips ECGs for power tubes, until the prices and availability(you try and find a NOS, matched octet of KT88s or 6550s of anything, anywhere), made that unrealistic for me. I've been VERY pleased with the latest interation of the Winged 'C'(St petersburg) 6550s(from Upscale). Still- My system needs six 6922s(early 60's Siemens CCa for me), and four 6SN7s(1 pair each- 40's Tung Sol CTL/6SN7GT round plates and Sylvania CHS/6SN7W, tall bottles please) The presentation makes any time/effort to locate, or any money spent, well worth it.

In the last two years I have owned my first tube amps. rogue audio m150s. I too was afraid of all the bad things that can happen with tubes. so far they [the promblems ] have not happened. when I first got them an output tube blew within the first few days, and it just blew a fuse, no damage to anything else, and rogue replaced the tube for free. after that ,not a singe problem. they drive my revel f32s with ease. they are very easy to bias because they have a built in meter, and by changing the bias level, you change the sound of the amps, way cool ! same thing with changing tubes, if you want your solid state amp to sound different, you have to buy a whole new amp. I have tried all sorts of 12ax7 driver tubes, and the cheap as dirt sovtek 12ax7 lps sounds best in my system. so much for only the realy expensive tubes sound best bs. I have also tried 6 different solid state amps against the rogues and no one of them has had the body or 3d sound of the m150s. I love them , so good luck, and happy listening ! chrissain.

I recently obtained on audiogon a Kt66 SET Sophia integrated amp just for fun and installed it in my system for a trial period driving Quad 989,s.It clearly was not in triode capable of driving to high volumes but sounded terrific doing the relaxed female vocal thing.28 watts in pentode and the quads were almost getting there with rock but not quite.This amp is a thing of beauty and a keeper so I decided to get a second hand pair of Living Voice Avatars so it could realy shine.And the combination is great,making some of the best music in the room ever.All was rosy until I plugged the Avatars into the VAC 70/70 for the first time and sat there mesmerized, I spent all evening well into the night digging out all kinds of music I had not listened to for eons.I had traded for these beautiful santos rosewood first generation Avatars In the thoughts of building the perfect low budget system and now am left wondering if I shouldnt consider moving up the living voice line and possibly replace the quads.So the down side of tubes are they are not all created equal,listening to them is addictive,Good ones usualy cost serious money great ones cost more,they cause you to spend money on other parts of the system.Something like great transistor amps.

"I spent all evening well into the night digging out all kinds of music I had not listened to for eons"

Don't you love it when that happens?

Well Brian congrats - that is what it is all about. I take it that none of your children or pets were injured, and your house didn't catch on fire? Thank heavens for that bit of luck given that you were in the presence of not just one but TWO tube amps.

Unsound mind, I guess you can add being mesmerized by the music and not hearing the fire alarm to your list of tube amp sins.

I think owning tubes is like being in love with someone. Sure there are compromises, but when it's right, you can't possibly imagine being without them. Rfogel has the right idea. I run the same Atma tube amp and preamp as him. I have been an Atma-sphere user for 20 years (my first set of their amps were almost 20 years old and in perfect condition when I sold them to buy the very latest version - I have since even become a dealer for them) Over the years I have tried some very good SS amps and preamps, and while they were quite good or even excellent, going to the tubes simply always bettered them, in many different ways. The tangible sonic characteristics, and the ones that can't be described, in that one finds themselves so much more "into the music" that goes beyond audiophile attributes.

Also I think owning a set of good tube gear can get one off the audio merry go round much more easily. I think it would be an interesting poll to see who upgrades their gear more often, tube or SS users. If my hunch is correct, than that would mean a considerable cost savings by not buying new gear so often.

I think when i was younger, I was also more impatient. I didn't want there to be any downtime fussing with tubes, and it annoyed me when I had to. I just wanted to listen to music.

Now I look at it as a process, and more of a hobby than just strictly listening to music. I know I may have to hunt down a microphonic or blown NOS tube every so often, but it is seldom and in my mind well worth the investment of time, for the 99.9% of time when I am enjoying the system so much.

Ultimately a well designed tube based system doesn't just make recordings sound nice, but makes them sound like the real thing.

Oh, and as far as tubby or uncontrolled bass, I recently posted about hearing an extremely well regarded speaker, with a well known SS amp that sounded thick and undefined in the bass. Another user posted back that that same combo produced those results when he heard them too. So it isn't just tubes that in the wrong combo can produce a lack of controlled bass.

To reply to the OP, the chief downsides of tube components are as follows:

1) you will have less time for your wife/GF/etc., leading to resentments if they are at all insecure.
2) your career will suffer as you spend way too much time listening to music instead of working.
3) your net worth will be diminished as you spend more coin on LPs and CDs, etc. than you did before emerging from the SS forest.

We put a Standby feature on our amps so that you could keep the amps warmed up 24/7 if you wanted to- and rated the amps accordingly. The nice thing about tubes is that if you want the system warmed up properly, it only takes about 3 hours, where solid state requires about a week. So IMO, why waste the energy- I don't run the amps 24/7 because I don't *have* to for best sound, though I certainly could and have done so many times in the past.

As proof of that I just came home from vacation and found that I had left my preamp on while I was gone. Sheesh- I hate wasting the power, but the preamp was none the worse for wear.

Anyway, if the tubes are in Standby (filaments but no B+), they will make very little heat (unless your amps use 6C33s). Most of the heat a tube amp makes is due to the class of operation, not the filaments. IMO if heat is what is the priority, your system is going to sound like it too. I would not call that a high end system- a high end system is all the stops out to create the realism and experience of music. To do that will make heat, tube or transistor not withstanding.

There is a common tendency to trade convenience for performance; digital vs analog and tubes vs transistors are examples of this tradeoff. If there was any way that transistors could be made to make the music that tubes can, I would not be making tube amps- but I put up with the base nature of tubes because also therein also lies the closest you are going to get to the music.

AMEN!!

"If there was any way that transistors could be made to make the music that tubes can, I would not be making tube amps"

Atmasphere, is there a scientific explanation for why this is? What is it exactly about tubes that inherently make them sound different than solid state?

Well. actually, a couple of decades ago Bob Carver demonstrated that characteristics of an audio amp can be taylored to match those of any other amp. Also, Behringer, (sorry about that Rodman99999) makes a device that can be added to a system to simulate tube sound. There is a selector switch to choose what tube type you want to match.

But if tubes turn you on, it's probably easier to just use tubes.

Mapman-I sure it has to do with the flow of electrons in solid state junctions of pnp or npn materials vs the flow in a vacuum from cathode to plate thru the grid(s) in your output tube; somehow harmonically there is a difference that can be heard.
I sure Ralph will expand on your question as well if he sees it;thats the best I can do.

Actually, Carver showed that an amp could be *modeled*, but even in his tests the modeling did not match the actual behavior of a tube amp.

Mapman, here are some primary differences.
1) Tubes are often much more linear than transistors. Triodes are the most linear form of amplification known. This results in far less need or no need at all for feedback to reduce distortion.

2) tubes produce mainly lower-ordered harmonics, transistors tend to produce higher ordered harmonics, especially odd-ordered. This can be easily seen in the overload characteristics of the amplifiers where these behaviors are exaggerated. Anyone who has run an amplifier into clipping and observed the output with an oscilloscope knows what I am talking about

3) tubes tend to high impedance while transistors tend to low impedance. In addition, there are capacitive effects in transistors that are magnified at higher currents. The effect of this is that both transistors and tubes will sound better (lower distortion, smoother sound, greater transparency) when driving higher impedances.

Atmasphere...As I recall (and it was a long time ago) after "modeling" Carver inserted networks to match what was modeled. Listening tests by a gang of golden ears were unable to distinguish the modeled amp from the real thing.

May I submit that a D/A conversion (digital amp) can be much more linear than any analog component (eg: tube).

Clipping characteristics are of academic interest. I don't operate my amps into clipping.

Eldartford-Was the modeling used by carver the t that he started to add in his amp names?

Atmasphere,

Are those things inherent in all tubes versus all transistors, or just more common in practice?

Also, if inherent, technically what is different that accounts for these differences?

Atmasphere,
1)Tubes are often much more linear than trasistors?
2)Eldartford already addressed this, but isn't easier/cheaper to keep ss amps away from overload?
3)Perhaps you can explain these "capacitive effects"?

No need to apologize Mr E- There are also companies that manufacture outboard effects pedals, and guitar amps with options, that attempt to digitally simulate the sound of tubed gear. The vast majority of us still opt for tubed amps though. Nothing sounds quite the same, after years of the real thing. Kinda like bank tellers: After they've handled real money for a while, they can tell fake stuff as soon as they touch it.

Eldartford, digital modeling amps have been around for years in the guitar world. As far as I can tell, people only play them out of desperation as they are a far cry from the thing that they are trying to model, i.e. a Marshall Plexi or Fender Twin. Its going to take more convincing than is possible in a thread to make modeling a plausible exercise for high end audio!

Mapman, not exactly. Pentodes are less linear in some ways than some CMOS devices, but still are more linear than a bipolar device. So the comment is a generalization, but only barely. In the case of triodes, there are no transistors, even the best fets and their variants, that are as linear.

Linearity in the device is a big deal if you want true audio/musical performance. Without it you will have to run less gain per stage and more feedback, making for a considerably more complex circuit. The simplicity of tube circuits is one of the ways that they rule over transistors.

Simple transistor circuits are rare. Their master is Nelson Pass. He has sorted out some of these simple facts, and built some of the best-sounding transistor amps around. But when you examine them, you will find that many of the so-called advantages of transistors (low output impedance, low heat) have been thrown out in favor of real advantages (performance that is musical to the human ear).

:) I just got home from a somewhat unsuccessfull fishing trip to Charlevoix and you guys have kept going on this thread and I found it's even in those three threads right on top. How did it get there? Really didn't plan on that.

Still don't have the amp as I need to wait how the whole GM thing will play out this week as unfortunately I work for a company which is directly affected by that. Hope I won't be knocking on the door of the unemploment office downtown next week.

Well, I shall keep coming back as I kinda like a thread with it's own heartbeat. As far as the usefullness goes I guess it has outlived it a little, yet if we were to no never through in something a little different this could be a somewhat boring forum.

Thanks guys

Krauti, GM as well as some other major car manufacturers are very capable of building some of the worlds best vehicles but it is a terrible shame that top management failed to make the transition from gasoline vehicles to greener transportation. They had plenty of time to contemplate this years ago. Global warmer is a serious threat and if we continue to on the path were on, no one will be employed. Will be too busy trying to survive.

Anyway there is a downside to everything, both solid state and tubes, just pick your poison.

Kruati, I bet next time you'll phrase your question differently. ;-)

98% of this thread is complete nonsense, but Phd's last post really took things down the crapper.

This thread has outlived it's usefulness and as Dan_ed points out, it's definitely gone "down the crapper" with Phd's asinine remarks. Maybe we should all scrap our inefficient gear and go with class D amps to save the planet. NOT!

When did this forum become so mean spirited? I can't rememeber when we've seen so many personal attacks in one thread. It would nice if we could return to succintly responding to queries and approriate discussions without the personal afronts. Perhaps those that feel the need to lower the standards of this type of dialogue should frequent that other site?

Unsound, perhaps you don't see that the majority of the posts on this thread are answering the question "what do I not like about tubes". After reading the original post by Krauti, the question being asked is really "if I own tubes, what do I need to know".

It would nice if we could return to succintly responding to queries and approriate discussions without the personal afronts.

And the bullshit political rhetoric as well! I don't care which moron or which moronic cause anyone supports in politics. It just doesn't belong here.

Dan ed, my comments in regards to GM were directly related to Krauti's last post that he was hopeful that he would still be employed by GM because of their recent filing for bankruptcy. So you see sir that that he himself injected a comment that had little to do with his own thread. I was just pointing out that part of GMs trouble is related to some of their failures to change.

A minority of members carry so much anger that they have to resort to cursing. It is ok with me, I know times are tough but it makes little sense to lose your credibilty even though the thread was briefly misdirected.

If every audiophile purchased class D amps, it still would have little effect on the enviroment since we as audiophiles represent a small segment of society. You buy what ever turns you on but my final comment that there is a downside to both tubes & solid state holds true and it's just a matter of chosing whatever turns you on.

Unsound your 100% correct - it is a real turnoff!

Phd, for me to continue would make me guilty of what you have done that I object to. These forums will become what all of us tolerate. You guys want political (Yes, discussions about GM and global warming ARE political) discussion, go right ahead. But there is already a forum that has been dragged down by that nonsense. It's called AA.

And if the word "bullshit" puts you guys off? Well, good luck to you all.

Just a little more on integrating the living voice avatars into the home system.I tried my old pair of vtl 225,s on the Avatars with great results lots of control and as I move the speakers around in the room searching for the perfect placement I am playing them mostly 4 feet from the side walls and just over 6 feet from the rear wall slightly toed in. The order of preference in amp choice of my available units is the vac,s then the sophia then the vtls.As the Avatars are so efficient small microphonic noises not audible on my other speakers become apparent and annoying between cuts.Source equipment quality changes very easily detected and the speakers are extremely transparent.I dug out a home built pair of supertweeters using focal T120 Ti,s and they are integrating well using a 1mf cap in line and the soundstage is wider deeper and imaging improved I really will have to get permanent enclosures completed for these and santos rosewood would be a safe choice.I think the only downside to your amp is that it may not have enough power if you wanted to change to less efficient speakers at a later date and you would greatly narrow your choices,but with the avatars no problems at all, I think they would play to satisfying levels with a transistor radio.

Thanks Brianhutch, always glad to hear from guys who run the same speakers. As I did buy these speakers with this particular amp in mind I think I'll be ok for the future. Also can't see myself wanting to change the system that much anytime soon.

If anything will change than it should be the sources as they will be the weakest link then.

For now I'll get the amp and we'll see what comes after that.

there is a risk that when purchasing a pair of allegedly matched tubes, there is a difference sonically, between them. i have experienced this myself.

Have fun, live and learn and most of all...enjoy the ride:O)

You become obsessed with tube rolling and spend way too much money doing it. "tongue-in-cheek" but also true.

MIke,

I think that can be true.

More toys to play with. That can be either good or bad.

I had fun tube rolling my Jolida 100. There weren't that many brands, and they were fairly cheap, including the best, the 5751 Sylvania black plate. That is until other folks found they liked them too. Within months, the price grew by 10 times.

Knowing what I found out about tube variety, I will not buy amps, and preamps. The cost is just too high. I watched a $600 tube get blown by a ham fisted listener spinning the bias knob. I could have cried for the owner, who just got finished telling us how long it took him to get the pair of big bottles.

I have been in and out from pretty serious SS gear to tubed designs and viceversa for the last 30 years, I learned to live with the mentioned tube disadvantages on behalf of the musicality and engagement they produce.

It happens to be that I got rid of SS amps at a faster rate than for tubed amps along the road.

Why not just put aside a few bucks eack week and get new tubes every 12-18 months? It's really not that much each week.

Polk - Good idea - but sometimes that saving flow shoud be a bit larger than a few bucks, I bought NOS Genelec KT88 at a thousand dollars the pack of 4 !!!!

Again... To me it worths every penny (and pain) the tube route.

Fernando

Exactly Fernando- I don't see ANY downside to tubes AT ALL. Your perspective will be based on your love for the sound of music.

For me it has mostly been about clarity or transparency. I want to sense that there is nothing between me and the players. Anything that dulls, rounds off or clouds the soundstage is unacceptable! Most tube based components get in the way, despite whatever plus they may offer.

>>07-23-09: Dave_b
Most tube based components get in the way<<

This clearly demonstrates a lack of experience.

Or poor listening skills.

Again.

No, it's called having ears Audiofeil. Again, I stated MY preference. I've owned several tube based systems and enjoyed them. System synergy is the most important aspect to getting good sound anyway, but in the end I prefer Pass, Krell, MF, Spectral etc. I have had tube preamps mated to SS amps with varying degrees of success as well. It's all good fun...unless someone invites YOU Audiofeil. Aren't you out of business yet?