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
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A Supratek DHT preamp would do the NS5000s justice.Say a Cabernet 300B/45 .Well worth trying with your Bryston power amps.
Other interesting integrated are Absolare (great sound) and Aavik.

Absolare (no dac, tubed input)
https://www.absolare.com/integratedAmplifier.html

Aavik (has dac). I have only hear another Aavik model but this is the newest
https://aavik-acoustics.com/products/u-380.html
As I said to yyz in dm. I may go from dual 4bsst (with sst2 mobo) to a single 14bsst2 with not much investment for the change. Hope thats not a side grade.