Solid state to tube

@ecpninja if you are more use to the type of drive your Meitner MTR-101 mono amps have now, and even though your speakers spec is 8ohm / 92db sensitivity, the room size and desired volume listening levels is a real factor to consider.  

Coming from your existing SS Mosfet amps, I could see why Will Vincent might lean you towards Mono amps instead of the ST70 stereo amp build he does.

If you go with Quicksilver and want more Transformer capability and drive, the Mono 60s, Monos 120s, or the latest QS Monos in order to run a wider array of output tubes ranging from low to higher power ranges, and different sound types.

Second up is a very inexpensive preamp that is, IMO, a tube rollers dream (and/or nightmare depending upon the individual).

I have gobs of the various tubes it can use (all old production) so it would be a nice dream, and fun, for me.

https://www.musicalparadise.ca/store/index.php?route=product/product&path=59&product_id=103

DeKay

Last up is a kit amp by Bottlehead (I've used their early inexpensive offerings for the past 20 years, thus the interest in this new product).

I was not aware of it until a recent "user" post that I read here on A'Gon.

If you are not interested in building a kit I think that they have someone (with a long standing positive reputation) mentioned in their forums/site who will do so.

DeKay

Lastly:

I thought that this inexpensive/well reviewed ($1500 300B based DH/SET) amplifier might be a fun option, but  due to the size of your listening room I'm not certain if it would work.

I gathered that you would like to limit expenditures @ $3k or less.

In my opinion the difference between decent DH/SET and other designs (excluding a few OTL amps I've heard) is not subtle.

DeKay

Quicksilver all the way. I love my Quicksilver Mid monos, and phono stage.