New speakers but old Rotel Amp


I got the Harbeths 30.2 XDs about a month ago and love them.
I have a PL Evo 300 preamp (an Evo 400 without balanced connectors), have a VPI Prime Signature TT with a Hana ML low output MC cartridge, a Musical Surroundings Phonomena (1st edition) phono stage that will be replaced next year, and my 19 year-old Rotel RB-981 amp.
I'm wondering if I should just get a PL Evo 400 amp, but the dealer I bought the speaker from said I could have done better, and is suggesting a BAT-56 (non SE) or a Rogue, or a Bryston 3B3 amp.
My budget was $5k, but listening to Riders on the Storm my wife heard so many new layers of the music she actually said the speakers were definitely worth the money and was interested in it sounding even better. I didn't tell her the stands were extra. The closest audio dealer is 45 min away and he suggested SimAudio. I was thinking tube amp not solid state.
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I think Rogue would be a wonderful choice.  The Stereo 100 is a nice amp for pure tube.  Countless great reviews and it is a first rate company.  

The Hydra is spectacular for a hybrid but the stock tubes leave something to be desired.  If you opted for the Hydra, you want a pair of Cifte NOS tubes as that will deliver incredible clarity and add to the soundstage. 

I personally own a Hydra and have used it to drive a variety of speakers.   
You can easily tweak / modify / damp the chassis of the RB981, eliminate the ringing of the internal heat sinks, replace the stock power cord ( I am aware it is not a removable cord ) with a quality, heavier gauge cord, change the feet, upgrade fuses, etc. If you are not familiar with doing any of this, or are afraid of opening it up, I can help you. MrD.
suggest you stick with a good sounding (better than rotel) class a/ab solid state amp, especially since you have tubes in the linestage already

harbeths (and esp. the monitor 30) can, imho, use good bass control that most lower cost tube amps have trouble with

many out there to choose from, but i suggest considering:

hegel
pass
ayre
luxman
mccormack

I would go with the Prima Luna Evo 400 amp. Synergy is the key to a great sounding system.