classe twenty five and classe fifteen

If that was true then the 15 would be 150 wpc and it's in fact 175 wpc.

I don't know about the DR15. 

The 25 in the DR25 is short for 250w into 8ohms

https://www.hifiengine.com/manual_library/classe-audio/dr-25.shtml

The idle current power consumption is around 100w with factory adjusted bias give or take. I took them up much higher so heatsinks were at 50c

Cheers George

Your link is standard specs and provides no support to your assertion that the 25 stands for 250wpc. As I stated, does that make sense when the dr15 has 175wpc? The DR 8 I suppose has 80wpc, the DR 9 has 90wpc and DR 3 has 30wpc? Do you honestly believe the DR 25 to be an outlier in the nomenclature?

Whatever

Jeez, the Model 10 amp was 120wpc, the 15 was 175wpc and the 25 was 250wpc. Taken directly from the specs in the owners manuals.   These are all into 8 ohms.  At 4 ohms they doubled their power.  I owned both the 10 and 15.  The 10 sounded better as the 15 was too dark sounding.  There is much better out there, used or not. 

The model numbers of the Classe amplifiers had nothing to do with the power rating.  They were close, but not exact.  Even the "Seventy" amp was rated at 75 watts.