My Roon CPU is on 88-103 (!!!) % while playing 44.1/16 tracks from 5 TB Thunderbolt HD. Two years old iMac with loads of RAM (20 GB). When I play Tidal (via Roon) it´s CPU is still 71 %.
UPDATE: Just checked Tidal running (without Roon) is about 0.9 %
Roon finished importing several days ago, but crashing every 3-4 hours or so today. My Mac is running hot, only running Roon (while typing this about 75 % CPU), Dirac (CPU 2.8%), Show Desktop (CPU 0.0 %), Quicksilver (CPU 0.4 %) and Safari (for typing this, otherwise it´s turned off - CPU 0.1 %)
KnockKnock ;=)