The maximum input voltage is 2.63174821 Volts

Actually, I can only make an educated guess that it is somewhere around the 2 volts that a standard CD player puts out. This would be easiest from an engineering point of view. I would think that an AGC would be kinda messy to engineer, one obvious problem being 'how long of a time constant do you build in?' If it wasn't right, the volume of the music would be rising and falling at most inappropriate times as the AGC hunts down the optimum input voltage. And what about classical music where there is one very quiet movement that goes on for minutes, followed by a sudden loud fortissimo? I just don't think any kind of AGC circuit would work well enough without messing with the dynamics of all the types of music and movie soundtracks out there. Of course, they have 144 db of dynamic range to play around with, so they don't need no stinking AGCs!

If my 950 wasn't in a very inaccessable rack, I would bench test this parameter; it would be easy to do. Of course, if they made the maximum input voltage really high, like 5 or 6 volts, the result would be that the analog to digital and back to analog conversion would be noisier than optimum. This _could_ be one reason the 950 is hissy in that mode. I have horn speakers that have 106db / 1 watt efficiency, and I can hear the hiss about 5 feet out - I consider myself lucky, as it could be a lot worse!