What do you see as the downside of tubes?

I have decided on getting a tube amp and it will be the integrated Mastersound 300B driving a pair of Living Voice Avatars, so at least that decision has been taken.

My main question is what you see as downsides of having a tube amp. As I've decided on getting an integrated tube it's really about what the downsides are I might want to know about beforehand.

The ones I'm aware are the following.

-The tubes need to be replaced and in the case of a 300B this will be somewhat costly.

-Bias is another issue but I'm not sure how big an issue. Do you plug in your meter every so often or just when you roll tubes or replace a dead one? The meter as such isn't gonna be a big issue as I don't think it's that expensive.

-Heat won't be a big issue as we have no kids nor a nosy dog that could get burned. Hope my electricity bill isn't gonna go through the roof, but then again, I can't quite imagine that.

I'd appreciate if you could add whatever your experiences are regarding this question are as I'd like to know more before I buy it.

You've hit all the primary points:

1) Higher operating cost due to tube replacement and increased AC draw
(unless you're coming from Class A solid state, in which case the AC use will
be comparable if the wattage of the amps are similar). 300B tubes are among
the costliest to replace.

2) More hands-on maintenance: biasing, checking and replacing tubes (be
sure to purchase a tube tester). Biasing is easy.

3) The amp's sound will slowly change as the tubes age, versus a solid state
amp's sound remaining constant. You may or may not notice the change in
sound over time.
I mostly agree with Tvad's item 3. The constant uncertainty detracts from enjoyment.
In regard to your item no. 3, (i.e. heat):

Don't forget that in addition to the worries about kids or pets getting burned by the hot tubes, that the heat from the tubes may increase the ambient room temperature several degrees, to the point that you might be uncomfortable sitting in your room after a couple hours of listening to music. This is usually only an issue though in the summer months, as in the winter you will actually appreciate the (rather costly) space heaters!
The major issues of tube amp ownership have been mentioned.

However, one factor for someone considering a tube amp is how well those issues match with the psychological predispositions of the owner. Whether "uncertainty" detracts from enjoyment is heavily dependent on the person involved.

I currently have a tube amp and have had many solid state and tube ones in the past. I've got no more "uncertainty" about the slow aging of my tubes than I do regarding the status of my car's tires or other consumable parts. They all fall into a category of expected "routine maintenance" for me.

Just as I don't run my car's tires until they are threadbare and unsafe, I periodically check my tubes with a tube tester I picked up on eBay a few years back. When readings indicate it is time, I just pop in new tubes, bias, and go back to listening.

Some people view the whole process differently. They might find they are happier overall with a solid state amp. As they say, "horses for courses."
This is usually only an issue though in the summer months, as in the winter you will actually appreciate the (rather costly) space heaters!
Oh so true with a pair of CAT JL-3's here in Minnesota.
I agree with the above comments.

1. Some people like the sound of tubes and like (or tolerate) the process of replacement/tinkering/service/expense with them.

2. Some people do not like (or tolerate) that process, even if they the like the sound.

3. Some people could care less or haven't experienced tubes properly.
Low damping factors that require speakers that do not need high damping in the bass. Limited load driving ability that requires speakers with sympathetic impedance curves, ie higher impedance and less variation. Sometimes, lower power that requires greater sensitivity in the partnering loudspeaker. Broadly speaking, greater cost per watt of power output. Potential exposure to high voltages, should the envelope of the vacuum tube be breached. These factors are often overlooked.
Three out of four of my tube amps don't work.
Major downside that has not been mentioned:

You will enjoy music so much more. Holographic imaging, silky midrange, liquid and smooth texture, air and bloom around each note, they are all addictive and intoxicating you might 1) lose sleep and listen all night long, 2) beat yourself up for not trying tube much earlier, 3) trip over cables walking in the dark to see the glowing tubes, 4) lose a few friends trying to save them from the dark side (SS).
I think Mlsstl has it exactly right. Whether you consider the extra fuss that tubes require a downside or an excuse to engage with your equipment depends on your perspective. I've found my Cary pre and amp to require minimal maintenance, just the occasional replacement of tubes as they wear out (and by occasional I mean every several years) and checking the bias of the amp.

Heat is an issue, as is the power demand of the amp.

A very big advantage in my mind is that you can make changes in the sound of your system by rolling tubes. All of the other tweaks you can do to improve sound are common to both tubes and SS, but rolling tubes gives you one more way of fine-tuning the sound.
The cost of a portable defibrillator.You just might need one when you are deep into the ether of musical nuance and a big power tube blows a fuse and you wonder if it took your speaker with it.Think Godzilla in Tokyo.
Heat heat, slowly destroying the other electronic parts, have been known to cause circuit fire, burning down the house, can't turn your back on them. In addition they are wearing themselves out as soon as they are turned on, eventually there will be a tube shortage & all the tube amp owners will end up using them for expensive paperweights. Other than that, tubes sound pretty darn good.
the biggest drawback is the amount of inefficent speakers my SET will not drive

Then it's the price of 300Bs....
One downside that has not been mentioned and for me is the biggest reason not to own tubes is having to power the system up and down all the time so that you don't use up the tube life not listening. I like my system on and ready to go all the time. I found when I had tubes sometimes I wouldn't bother playing music if I only had 15 minutes or so. It just wasn't worth the hassle. Another thing that bugged me was a few different tube pieces I had could take up to 90 seconds to be ready to play. I had a CJ preamp and I would turn it on and then stand there until it clicked on and then adjust the volume so I could listen.

I think tubes sound great but so does solid state. Some people like the ritual of turning on the tubes and the fuss I'm sure.
Tbadder,"3 out of 4 tube amps don't work" That's God telling you you have too much money.
What Semi said, times 2
My tube amp (Pacific Creek E34i - 45 Watt PP) has difficulty sourcing a lot of current needed to drive speakers with low impedance in the lower registers. I've found this to be the case with my Vandersteen 2s. However, in the case of my Monitor Audio Silver RS6s, they are high enough efficiency and don't have such an impedance dip at low frequency to cause a lack of dynamics and transient response in the low end.
I'll quote from my virtual system:

...I wanted to go back to solid state. I've had tubes for years and loved them. I mean really loved them. However, there are compromises I'm willing to make because 1) I want something I can leave on 24x7, 2) I need something that doesn't generate as much heat, 3) I don't want to continuously wonder if a NOS set of Pope 6SN7s sound better than my NOS RCAs or if my 12BZ7s are aging and need to be replaced, and 4) I want hardware that doesn't require as much real estate.
Finding quiet, high quality, good sounding unused tubes.
I've owned some very good and quite expensive SS gear over the years but none of it has ever sounded(to my ears) as believable or satisfying as even modestly priced tube gear.

Many years ago, after hearing so many good things about tubes, I decided to replace my SS Symphonic Line RG-4 monos($9800pr) with a pair of 60wpc QuickSilver's(maybe $1500 pr). Long story short, no contest. The QuickSilvers just plain sounded more believable; more flesh on the bones, more relaxing and just plain more enjoyable. I found myself listening more often and for longer periods without the usual boredom setting in. The only downside to the QuickSilvers was their rather wimpy bass but I really didn't mind since everything else was so good.

After three years with the QuickSilvers I moved on to CJ monos(2 years), VTL monos(7 years) and five different CAT preamps over at least 15 years. Other than a power tube in one of the CJ's causing me some minor grief and an occasional re-tube, all of my tube gear has been trouble free

Over the years I've auditioned various SS amps and preamps and as good as they've been tonally, they always come across sounding 2-dimensional and rather uninvolving(to me).

Currently I'm suffering(NOT) with an Atma-Sphere MP-1 Mk3(w/phono) and MA-1 Mk 3 monos. Let's see, that's 56 tubes not including the four in my tubed CD player. For almost two years my A-S gear has been totally trouble free and the Telefunken ECC88's in my CD player are still kicking after being used in those 5 CATs over the 15 years. Not bad!

The downside to tube gear, it can be addicting. You probably won't want to go back to SS. Yah, you may have to bias your integrated on rare occasions and depending on how hard the tubes are driven you may need to replace a few of them over time.

Unless you're completely neurotic I doubt you'll be worrying about the status of your tubes while you're enjoying the music. That has got to be one of the lamest reasons for not going with tubes I've read!

Heat may or may not be an issue depending on your room but even with my 28 power tubes running Class A, it's not for me.

As EveAnna Manley would say, "Tubes Rule".
If a tube amp (or a class A solid state amp, for that matter) is located in close proximity to a room/house thermostat, it can create havoc with maintaining a constant room or house temperature.
The real down side is that you may be perceived as a picky person and ordinary things are not good enough for you. You pursuit your ideal to the extreme and don't make compromises for the 2nd best. You are too confident in what you believe. Anyway, you are just above this world...... ;-)
I believe the importance of what was mentioned earlier about the difficulty obtaining good quality, quiet, vintage tubes should be carefully considered. Tube gear can provide real benefits, but finding the tubes...and opening the wallet...can become a hassle unless one has deep pockets and lots of patience.
The tubes glowing in the dark make for a great ambiance. You may end up spending more time at home. It's even better if you can share that glow with someone else. It even works for us old married guys.
But a Lava Lamp is even better and requires less maintenance.
Mastersound makes great amplifiers. Enjoy! Tube amps need such simple maintenance. If you can change the oil in your lawnmower you will have no problem maintaining a tube amp. If you have to bring the lawnmower in for a new engine because you blew it up, think again.

As for the costs, you just dropped more than the cost of a car for 30% of the population. It will be worth the cost of tubes every couple years.
Every tube has it's own sound signature. Even so, I have them in my DAC, and that is what I hear. So, I guess I am a fan of tubes, as long as they are little ones in my DAC.
My friend has two lava lamps, Carver electronics and Double Advents, and a Members Only jacket.
Not sure if anyone mentioned that some tube amps may take a while to warm up and sound right after turned on.

I think tubes at the line stage level in the source or pre-amp rather than in the power amp are a lower impact way to get some of the merits of good tube sound while minimizing the exposure to some of the downsides mentioned. That's where I am with my system at present.
My friend has two lava lamps, Carver electronics and Double Advents, and a Members Only jacket.
Bizango1 (Threads | Answers)
You know Mr. Malolepsy, my junior high gym teacher?
For me the downside is lack of power, and thus
compatibility with my speakers...Usher 6381 that Usher states are mated better with SS. I'm guessing its because they're probably difficult to drive adequately with most tube amps. I'm bummed, I'd love to try one.
Wow, I've never received more replies to a post than this one. Guess what Semi said is what convinced me most :)

Seems that the availability of tubes will be the biggest issue to be considered, followed by the heat. As I don't listen for long stretches of time the heat should be tolerable and knowing that tubes are expensive simply means that I'll have some fun looking for them right away while they are still available.

Haven't actually dropped the money for it yet but will very soon and can't wait to get it. Right now I'm using my old Denon receiver and it's not quite what I want to use on the long run, otherwise I could have kept my Electrocompaniets as these of course were a lot nicer as far as SS stuff goes than the Denon.

Well, glad I got all the replies and feel highly encouraged to go for the tubes. The only direction I could imagine changing my mind to is to a tube amp that uses more affordable tubes and I'm not really considering that yet.

Thanks again
The heat is really only an issue if you don't use a tube cage and have small kids. I hate being hot. Yet I am not warmed up by the tubes in either of my two main rigs each uses either 8 output tubes fat botle 6CA7s or KT-88s.
I own 7 tube amps all work.
I own 4 SS amps 3 work.
Of all the preamp tubes I have used only one just one burnt out unexpectedly. The out put tubes in the past 7 years required 2 new sets and after two burnt out in that entire time giving me cause to replace all. Only one time did a now notorious KT77 go down requiring repairs.
The downside is the comment regarding the enormous variety of tubes to try. It can and did get ridiculous in my case fast. Output tubes cost too much to play around with very often.
The sound of a good tube is magical we all know this. Therefore when one gives you more magic it reinforces the idea that you should persue as yet others at first. Then you can honestly settle on your preferences and feel comfortable. I know the 12AU7 I like better than all the others I care to try I also know the 6922 I prefer. My largestbsingle group are 6SN7s but I am very close to shutting the book on that as well.
A downside is that there is no meter on the tubes telling you when they have given their best so you may experience mysterious declines in the tube magic.
I have some solid state for specific applications that you wish tubes would do just as well, but don't. The price of the finite number of NOS/OS tubes has made owning some classics quite prohibitive. A fortunate upsurge in the quality of new production helps alleviate the need for NOS. has made enormous strides but they are not cheap either.
Maybe it is just my luck but my SS amps have had at least as many issues as my tube amps.
Yes turning the rig off is a pain especially when it's the middle of a good session and the tubes are humming (figuratively). That is when they are simply glorious the downside is hearing the march to being in top operation every session knowing it will take time, you can't help but notice the delay.
I am a convert. Until I say I have had it! No more tweaking. And stick with just one rig and one favorite tube for each position and the search for a slightly better tube layout and brands is an albatross around your neck. When the economy didn't hurt me personally, the hunt for the best combination was fun. If I had to start now it would be quite onerous.
I hope my kids will like tubes when they get older and appreciate the collection I have. If not I better put a coda on my will.
As Eve Anna says, tubes rule. The other stuff pales into insignificance, for me at least Good luck, Dave
300b tubes are readily available as are all the other tubes mastersound uses. These tubes are all in current production. So many choices in new tubes plus if you want to roll tubes lots of vintage choices.
One of my output tubes flamed, welding itself to the socket and otherwise doing some damage to the amp. The amp's fuse blew, but not before a power surge blew out all the resistors in the crossover to one of the tweeters. The amp manufacturer repaired the amp, and the speaker manufacturer repaired the speaker. The speaker manufacturer maintained that the tolerances of the resistors would have withstood a surge from a solid state amp. My system is now all solid state. I like a quiet life.
Kusina, wow!

Gotta admit that as someone who just wants to spend as much time as possible listening to good sounding music for reasonable cost high power tube amps employing many tubes in particular do scare me. I'm sure they are fantastic when things are going right but when something goes wrong, then what? Even in lieu of a big bang like Kusina relates, it must take considerable time and energy to replace just the bad tube or tubes when needed.

I have one tube in my DAC, 3 in my phono section and 3 in my pre-amp line level stage. I've been running this setup for about half a year now without issue, but frankly, the thought of dealing with a tube amp capable of delivering in my system scares the crap out of me.

If I used high efficiency horns or some other high efficiency speaker design that did not require lots of juice to sound good, I might take the plunge.

Actually, my 2nd 2 channel A/V system running the Triangle Titus 202s fits that bill. Maybe someday there.....
I've seen a few mythologies espoused on this thread so maybe we can sort some out.

Triode-based amplifiers tend to have very consistent performance over the life of the tubes, which in general also lost longer. In this case, Krauti is considering a triode amp. Pentode tubes do degrade much faster, with far less consistent performance.

The idea of 'damping factor' is confusing and not helpful. It is certainly **not** required to produce deep, articulate bass with plenty of authority and slam. All speakers and amplifiers do not work together; if for example you think that because you have a solid state amplifier it will drive anything, think again. There are plenty of speakers out there that it will not be able to drive correctly, just as if you have a tube amp, there are plenty of speakers out there where the same applies. It is in fact a matter of equipment matching in all cases, see
http://www.atma-sphere.com/papers/paradigm_paper2.html for more info.

Heat: if properly designed, the components in a tube amp will last as long as they will in a solid state amp. Its as simple as that- otherwise we would not see vintage tube amps still in service after 50 years...

Also, it is a fact that class A operation makes for the best sound (all other things being equal that is), whether tube or transistor. So if we are talking about a tube amplifier, the heat it makes will be only slightly higher than a transistor amp that makes the same power. Granted, the heat **sources** are more concentrated in a tube amp, but for the record the difference between tube and solid state **if we are talking about class A operation** (and we are in this case), is only about 15%. IOW, the heat comes from the class of operation, not so much the device. Try running a transistor in class A with no heat sink and see how hot it gets (hint- it can melt plastic)!
What a great thread! I have been fascinated by tube amps for years and have never had the money or gumption to go that way,though the systems that I have heard have been magical.I am leaning more and more toward taking the plunge and going with a tube rig.I have a set of the original Snell "E 1s" and they should be a good fit for a tube amp or integrated.My main system has Acoustat 2s and unless I could aquire some serious big mono blocks would be a problem to drive.(If this is faulty thinking please say so)
The Dynaco ST70 and the upgrades/restorations available seem like a good starter path.Also I was thinking a tube preamp for the Acoustats might bring a touch of the tube sweetness I long for.
The Dynaco refurb route has a certain symmetry for me because I am driving the Acoustats with a Hafler 220,so I would have David Hafler's early and latest designs to compare a contrast.Also, it seems to me that since there are so many of them in use still that they must be doing something right.
The idea of tweaking and tube rolling sounds fun and interesting to me as well.Nothing is more fun than tweaking and discovering new magic in your system;after all,this is a hobby.
As for tubes going away in production;it seems that the Chinese and Russians are making them (military grade)in great number.(planning for Nuclear winter?)
Now if this recession/depression would just turn around,I could start shopping.:-)
I lost patience in trying to read all of the above - here are some random thoughts:

Viridian makes the most important comment in my mind - you have to spend a lot of money on a tube amp to get a good one, i.e., one having power supplies and output transformers of sufficient quality to enable it to properly drive most audiophile speakers. It's hard and risky to define "a lot", but let's say well north of $10k retail - many (if not most) tube amps are overrated and not understood by their purchasers.

Your Living Voice speakers, however, are excellent and present a benign impedence load, allowing you a lot more flexibility with respect to amp choice. I have no personal experience with the Mastersound amps. I do not want to steer you away from single-ended amps on Living Voice speakers, but a hassle-free tube amp that is really well built and sounds truly great is the VAC Renaissance 30/30 push-pull amp. It biases the output tubes automatically and has a tube shut-down feature that kills the power to any output tube that is about to blow (these features take all of the hassle out of owning a tube amp). All point-to-point wired (no boards on those babies). It runs four 300-B's and puts out 32 watts/channel - it would sound like a 600 watt/channel Krell on a highly efficient speaker like the Living Voice.

Despite the high initial downstroke, good 300-B's (Sophia Electric, Full Music, E.A.T.) will last a very long time (10,000+ hours / 5+ years).

While some tube gear is truly problematic to own, a high-quality tube amp running standard-fare pentode or triode output tubes is arguably more "reliable" in the long run than certain high-end solid-state designs - when a tube amp is retubed, it's basically a brand-new amp, while some high-end solid-state designs have been known to become irreparable because they use rarefied output transistors that go out of production. Also, you replace output tubes, while a $50/hour tech repairs the solid-state amp you had to pack up and send away to him.

A high-powered tube amp that uses a lot of output tubes can be a pain in the ass to own because of the higher likelihood of tubes losing bias and fact that easy biasing is not always a design priority (Brunhilde and Wotan owners with burnt fingers know what I'm talking about). However, if you are running a single-ended amp with one or two output tubes, or a high-quality amp that auto-biases like a VAC Renaissance or Audio Valve, there is little or no more demanded of the owner than with a typical solid-state design.
You don't have "to spend more than $10K to get a good tube amp" That's simply a fairy tale.
Raquel, just a FWIW, we probably have as many tubes in our amps as anybody, but they are autobias and hold together quite well, even if a tube fails. Having a lot of tubes does not have to be a pain in the neck if the amp is designed properly.
Rolled off highs, bloated bass? :-)
Hard to tell, Madfloyd, if your post is a question, or sarcastic statement.

I can say from experience, rolled of highs and bloated bass do not have to be a
downside of tubes provided the amp/speaker match is correct.
Regarding the comment by Markwatkiss about supposed fairy tales, high quality output transformers are mandatory (as are hefty power supplies) for controlling the woofers in the typical audiophile speaker featuring a 4 Ohm or less load in the bass, and they are extremely expensive. I am not aware of any tube amp that retails for less than $10k that can properly control the woofers of such speakers assuming a normal listening room and average program material.

Ralph (Atmasphere): I agree. I have owned auto-biasing VAC Renaissance 140 monoblocks (sixteen 300-B's) or a VAC 70/70 (eight 300-B's) for almost nine years - they have been completely trouble-free. Having an amp that, if I may quote you, "is designed properly" is the key - cheap tube amps do not play in your league.
How do you reliably diagnose the bad or failing tubes for replacement when an amp has so many tubes in use?
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.
Every time I come back there's more. Looks like I started a small avalanche here :)

I shall take a look at the amps mentioned in the thread though so far I haven't chamged my mind. The only thing I don't like so much is the price of tubes. But at least it seems one can get them. Can't say that about ammo for my target gun (hmmm, yeah, sometimes I like things that make boom.

The other thing that does seem to crystalize is that there is somewhat of a potential for damage to the speakers if a tube says goodby in the shape of a wee supernova. Is there anything that can be done to prevent any downstream damage like additional fuses?

Well, thanks again and I shall check back later on.
Nice thread and some very good points both pro and con. I like the sound of tube amp and the ease of a good sounding SS amp, I use both, but all of my SS amps lean toward the sound of tube amp. Since I also own the Mastersound 300B SE I am going to address your questions with this amp in mind. The Mastersound only has 6 tubes, 2 of which are the 300Bs so heat is not really much of an issue, compared to most tube amps this one runs pretty cool. My Mastersound amp is the higher output version which uses either the 32B or 300BXLS tubes and yes these tubes are quite expensive, probably around $625 for a pair of 300BXLS tubes, the 32B tubes cost much more. However, new regular 300B tubes can be found for around $150 for EH to around $350 for a pair of really nice Full Music Mesh Plates all the way up to very expensive Western Electrics with various price points all the way up. The other tubes, 5687s and 12au7s are very inexpensive, so overall tube replacement is not all that expensive or much of an issue.
Biasing the 300Bs will require a meter but those are cheap and biasing the output tubes only takes a few minutes. Once the tubes settle in I only need to check the bias about once a month and rarely do I have to make any adjustments. So overall the downside to this particular amp is very small in relation to the sound it produces.
I was a solid state amp/tube pre-amp man for years. My systems sounded great. Then I purchased Canary monoblock tube power amps and mono-block pre-amplifiers. I have not listened to my superb solid state set-up 30 minutes over the last month or so.

The sound of an all tube system is so seductive. Semi hit the nail on the head, at least for me, in his post. I don't like the maintenance but I am now convinced that the sound of tube amps make the headaches of biasing and testing tubes worth it.

Now that I have tried tubes, I will never go back.........