marantz pm8006 vs peahtree nova 150.

I would look into some Rega analog integrated amps. All Rega integrateds are analog no DAC class AB amp design. Sounded fantastic very refined smooth very musical tend to be on a warm side of neutral but it isn't like tubey warm, no, nothing like that. 
Rega integrated amps range in prices from around $1500 to $10k. 
If you can swing $3k I highly recommend the Rega Elicit-R integrated retails for $3k new unless if you can find a used for probably around $2k and less. 

This may work? Rogue Audio Sphinx V2 Integrated Amplifier, if you don't mind used versions you can swing some excellent integrated amps that may not have all bells and whistles but can be sonically better performing.  Well your Tannoy xt6f is around 88 dB/1 W/1 M ?

Hi---I have the 8006 with a pair of Dynaudio Special 40s which like lots of power--they're not very efficient but sound incredible. The 8006 can be used as a preamp if you need more power. :)