Amp and Preamp recommendations for Yamaha NS5000


Currently have SOTM 200 ultra -> denafrips terminator +dsp board -> Audio gd he9 pre amp -> dual bryston 4bsst -> NS5000.
I am loving the sound... just sounds incredible. But wonder about amp and pre amp upgrades down the road. Any thoughts on what might work well? These speakers are 87 db efficient.
So far thinking all pass labs amps + pre.

Ok with buying used. Would like to keep things under $20k if I can. Thanks.
smodtactical
Wow, you want to keep under 20K?!!! Wth!

 You can get a great amp and preamp for SOOOOO MUCH LESS!!

use the rest for a CD player and a boatload of music!
and a down payment on a new car
YYZ did you already buy the ns5000? Would really love to hear what you think about the benchmark and Coda amps on the ns5000.
@arctikdeth Can you tell me what amp you recommend that would be better than my dual 4bsst?
Also no interest in CDs so i can focus on the amp.
@georgehifi what would you recommend for YG Hailey 2.2s? Unfortunately not sure measurements available and they are more efficient than the Sonjas and older Haileys.
@georgehifi what would you recommend for YG Hailey 2.2s

Sorry Keith, never heard them.
Also from what I can find, no "independent load measurements" has ever been done on them to see what kind of amp would really be suitable.
They apparently dip into 3ohms, I'd like to see where? and for how long?, also if there's high negative phase angle also at that frequency, they can easily start to look like 2ohm or even 1ohm to the amp.
Safe bet to run an amp like the Gryphon Diablo into them or a cheaper Parasound Halo A21+ or Halo JC1's if you can afford them.

Cheers George 
@ smodtactical Not yet, I am buying that last. I got a new DAC, preamp, headphones, and XLR’s this month. A pair of AHB2 amps are next and then the second amp. The speakers are going to be last because I think Yamaha will release a smaller NS 4000 sometime this year. They have already released a NS 3000 monitor. A smaller speaker would work better in my room, which is smaller than yours. However, if that does not come out then I will get the NS 5000 and use the Convolution file processing on ROON that I mentioned to you before to fit the speaker in the room.

I get the AHB2 after July 15th USA tax day. The second amp I hope around September.