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.

Thanks
krauti
I was never more seriously involved with the music and this hobby until I started acquiring tube equipment. I don't see any downside at all. I personally would never consider the cost of tubes or biasing to be a downside. It's no different than performing maintenance on your automobile. Of course, this is just my opinion!
Unless you or your pets (or both) are having sex with the the amp, I wouldn't think burns would be an issue. No more than a hot stove and usually a warning will suffice there for those that don't know better (or they'll learn fast enough). Besides, most have covers or grills.

The majority of new tube amps should be reliable, but if replacing lightbulbs in your home is too much of a headache, then a tube amp may not be the answer.

I've owned both, to me my current tube amp sounds the best of any I've owned and it does great in home theater duty too.
Raquel's original comment had me somewhat baffled; the follow up post clarified things. A 4 ohm load is harder to drive and to do it properly does require more from an amp. That's not the case with a more efficient load. A properly matched system can work well with a "lesser" amp in a well matched system, though at some point a matter of "degrees" will creep into any discussion of audio equipment.

Unsound makes some interesting points. In my limited experience there's validity to them all, but, again, it comes down to matching equipment. But Unsound also makes the best argument of ALL for tubes, albeit indirectly. They keep life exciting! Taking my Seedwings Sensor (Google it) out most weekends isn't enough. I need the excitement of tubes, too! :-)
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my twin boys grew up with big tube amps sitting on the floor, wide open without cage. no, they never got burn.

my friend puts it best. if you can train a tiger to perform in circus, you can train your kids not to touch the tubes.