Please give me some suggestion on tube amp

Hi all,
I'm in process of upgrade my 2-channel system and need your suggestion/help. My current system:
Theta David II transport
Stax x1t DAC
Clearaudio Champion Level II
Clearaudio Tangent Linear arm
zyx airy 2 Cartridge
Tom Evans Groove phono
Emotive Audio Sira-LE
Mastersound Reference 845
SAP J2001 MkII (Italian Hybrid Horn)
Nordost, Siltech & Virtual Dynamic top of the line
Hydra 8 (original)
PS Audio high current AC filter
Symposium Rollerblocks Tweak
SAP speaker stand Special for the J2001 Tweak

I'm happy with the system right now. However, lately I want to try bi-amp with the speakers to bring out the max performing. I just ordered a crossover from Marchand, model XM-126S-2AA, 2-way crossover, all vacuum tube w/separate power supply; low pass filter @ 800 Hz w/ 12dB per octave slope; high pass filter @ 800 Hz w/12 dB per octave slope; with attenuators (since my preamp only have 1 output).
I will have the Mastersound (40w/2x845 tube per side) for the high and mid. So here is the question. What tube amp should I get for the woofer. My budget range around 3-5k. Any suggestion and recommendation will be greatly appreciate. Thanks!
Link to my current system:
Beautiful system and listening room. Magical setting and sound, by the looks of it!
For this part of the musical spectrum there is a reasonably priced, over-achieving dual channel amp from, the Aronov LS-960. Very exquisite detail in the bass with control and extension truly rivaling best solid state. In the aesthetic context of your system, its in person elegant appearance should fit right in. Sonically, this company's amps somehow elicit the best bass from many speaker designs I have heard driven by it. And there is the monoblock version if two boxes would not be too room filling, and BASS is to be the boss.
Thanks for the reply. I'm serious looking into the mono blocks version. Would greatly appreciate if some one can share their thinking about this amp.
Holly Cow-

No advice for you, just want to say that I love your room. Looks like it feels as relaxing as the sound eminating from your speakers. Very Very Nice.

Thanks Tickfight. The room is an absolute need for me to relax after all the working day time.
I decided to go with Aronov mono blocks for the woofer. Just purchased them 10 min. ago :)
Thanks for all the input and suggestions.

Happy listening!
Wow! Killer listening room and set up... You’re in deep and it looks all good. Linkoping, you have excellent taste. As for your amp question, have you listened to OTL's mono blocks like Atma-Sphere? They really bring out the textural detail and have a better than average (tube) slam on the lower level signal. I don't miss my SS amps at all in that regard. Fact is, they sound great through the whole audible range and they have plenty of muscle watt wise. Enjoy!