Magneplanar 3.7 - recommended preamp and amp

I own 3.6s
If I had to use a less expensive preamp I would be using an Audio Research Sp-15. The Sp-15 has a great three tube phono section, the rest is SS.
I got one a few years back for $1,500.
That $ was a little low, but that particular ARC item is not well known.
It is a great preamp for the price.
Hard to find though.
Another gem is the VAC Standard and is also around $1,500. Also rare. (I own both, neither for sale!!! even though my main preamp is a Bryston BP-26)
Both have separate power supplies.
Spend the rest on the amp. A used Bryston 4B-SST or 4B-SST2 could be found. Do not settle for a Bryston 4B-ST.

I replaced my Cary 500MB's with Cary 500.1MB's. Like many others (search the forums), I find the Cary/Maggie combo to be terrific. I have also found the Cary's low input impedance and high input sensitivity make them ideal for using a passive pre, and have found the Promitheus TVC's a great choice. You don't indicate if you can get by with a line level pre or have a vinyl rig. You should be able to hit the low end of your range with a Promethius Ref 4 and the Cary 500MB's. I used that exact combo in a room about the same size as yours, and was never hurting for volume. I don't have a specific recommendation on a full feature pre, but the BAT/VAC/AR's mentioned above seem reasonable. I'm skeptical as to the prospects of finding an integrated that will bring out the best the 3.7's have to offer. Full disclosure--- I still have my old Cary 500's sitting in my living room. If in the end, you decide to give those a try, let me know and I will list them. Otherwise, they are going to sit until I put out all the other fires I have going.

If you'd like to discuss in more detail, contact me directly through my ads for the Revel Salon2s and the Esoteric X0-5.

The recommendations by Elizabeth are great and add to that the 7Bst and 14Bst from Bryston. Pass labs is also very good. Just be sure to get at least 350-400wpc into 4 ohms. Great speakers. Jallen

Thanks for everyone's response. I am open to using a tube preamp coupled to a solid state amp (I've done that before). I'll look in them.
Jallen- for Pass amps do you think there are some that would provide enough drive and yet be within my price range?

I am also thinking about a Odyysey amp as it seems to be a good value for the money.

I will also check into the Bryston amps--appreciate everyone's comments about the various models.