Out of sheer necessity, I used to be archi-conservative (please note lower case in 'c' of conservative) in the use of my system. . . my Rowland 7Ms and the ARC Ref 3 were all gas guzzlers. . . my wife noticed with horror, whenever my stereo was active more than a few hours per week, that our power bill quickly grew into undesirable regions. . . One year ago my Ref 3 has been switched to a JRDG capri, which draws only 6W, and the 7Ms have been replaced by a class D JRDG 312 which runs as cool as a cuke. My stereo is now on 24/7 making music sounding better than ever. . . and my wife has not made a peep about power bills ever since.