Tube Amps Watts vs SS amp

You are better off using that speaker with solid state. It is not an easy speaker to use with tubes!
http://www.thevintageknob.org/acoustic_research-AR9.html

Oh no...

One of those SS watts threads!

Someone explain to the OP how he isn't even listening 20 watts of power.

If you are starting with the premise that you need 400 wpc, and you have a somewhat tight budget restriction, most tube amps are not good candidates.  I think that even ultra expensive high powered tube amps don't sound very good and would stick with solid state for delivering that kind of power.

But, are you certain you really need that kind of power?  There are meters that can tell you how many watts are being delivered to your speakers.  If you use one of these meters while playing at typical volume levels and at the highest volume levels you play your system at, you will have a better idea of your power requirements.  If it turns out you do need more than 50 watts, it might best to just stick with solid state.