-> Did QSC buy out Stewart, or just try to copy the idea while -> 
sidestepping the patents?
 TT> I'm not exactly sure what you're speaking of.  I don't have any
 TT> knowledge of Stewart's product line - I don't even know if they make a
 TT> large format amplifier - to respond to this statement.
Stewart was a new startup company several years ago.  4 or 5 years ago at AES 
NYC they were annonymously advertising for a design engineer to work out 
details of a pair of products they were demoing the following show there.  
Those amps sound like they could be what you described from QSC, with 1800 
watts from a 2 RU 17 lb. box, and a smaller 1 RU unit.  
They obtained the light weight by avoiding iron, direct rectifying the AC 
power line rather than use a transformer.  They obtain bipolar rails, 
efficiency, and safety isolation by using a smart SCR rectifier for primary 
power and only rectifying a little more energy than the audio amp needs, and 
then feeding that to an ultrasonic toroid based DC>DC converter.  
Terry
--- Maximus 2.01wb
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