Bryston 4B3 or 14B3 ?

BHK labs measured the 4B3 at 354W into 8 Ohms, and 552W into 4 Ohms.  Bryston is conservative with their power ratings.  I chose the 4B3 to power my Magnepans and find it to be perfectly neutral and clean. I can not imagine ever needing more power or SPL than is provided by my 4B3.  IMHO it is the sweet spot in their line up but I do use Tube Pre-amplification to add texture. There is a difference in input impedance which made the 4B3 a better choice for me. The 4B3 measures at 29k/20K balance/unbalanced.

If you are using a Mytek for your DAC, strongly suggest you use a preamp.  I've had several instances of static causing the volume control to hit max.

I just bought a Bryston headphone amp and owned about 5 other 2 channel Bryston amps. I would not pair Bryston with any speaker with Beryllium. Not sure if this Focal has Be.