Thank you @Dan
Assuming same as Cascade they both have a do not exceed for prolonged periods temp of 122F (50C).
Director (Steady State): 24W
PowerBase (Steady State): 225W
Forced air cooling using 24 degree ambient and 40 at the heatsink is 48.25 CFM (ideal) but 100 CFM (realistic). The good news is these numbers are fairly low and achievable at very low noise levels
The Sentinel draws relatively constant power that does not change based on playback state, but will change slightly based on changes to mains voltage. Higher mains voltages than 120 volts, or 240 volts, AC will result in slightly higher power than the 250 watts total and lower mains voltages will result in slightly lower power consuption. Other than the inrush current when the Sentinel is turned on and about 10 watts greater dissipation while the Sentinel is warming up its clock ovens (about 3 minutes) the Sentinels power draw is constant. Unlike an amplifier you do not need to budget any additional dynamic power.
@Dustin_Symanski Thank you, I am just double checking my forced air approach, I will need to perform the same calculation on the Sentinel Amp once you can share the numbers but so far it seems very doable 
