What do you see as the downside of tubes?

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.