Simple: high-end quality build parts in a top-end high-end French design, with quality labour in France = A top-end performer.
AUDIO REFINEMENT ("AR") was their cheaper second line offering - a designed-in-France kit with YBA designed family parts but assembled in China line.
Personally, I can speak to the AR prowess. I scrapped my very top-end 7.1 CAMBRIDGE AVR in favour of separates:
- AUDIO REFINEMENT separate 3 channel power amp and
- separate AR 2 channel power amp along with
- a quality built separate USA AV pre-amp processor and
- direct pass-through my main 2-channel integrated.
The sonic improvements over the AVR were not subtle with the AR power amps introduction.... They were a fine complement to my REGA OSIRIS integrated amp
highly recommended.