You are barking up the wrong tree for quiet or bedroom volumes.

A 100-watt JCM-800 is loud enough for an 2000+ seat auditorium gig without a PA system.  With the exception of playing clean outdoors, I could imagine ever needing that kind of power gigging in the cities I've lived in (LA, Vancouver or DC), the clubs were just never that big and most had noise restrictions.

But the amp is totally unsuited for quiet or bedroom playing.  Tube amps, in general, are poor bedroom solutions, the tubes have a certain saturation point before they even "turn on" and are often too loud at that point.  Even a 5-watt amp is too loud or very difficult to tame to bedroom volume.  Though attenuators, voltage/power scaling, and master volumes can be use to reduce the volume of small amps, bedroom volume requires a serious compromise in tone.  But a 100-watt amp?  No way.  Even playing distorted at low volumes means using buzzy preamp distortion only with no power amp overdrive to thicken it up. 

SS amps and modellers are far better bedroom solutions.  You just can't find an amp that does everything.