seek a threashold power amplifier


in the 80s,threshold sold a mono block power amps.one class a and one class a/b.i seek the class a/b to buy.maybe not available because none sold.do not remember tag or model name.it was listed as 1 horsepower at 8 ohms.look up watts horsepower conversion table.the class a and class a/b were indentical cabinets.huge.the current mcintosh labs power amps mc2kw are 2000 watts at 2 4 8 ohms.about 3 horsepower and cost a fortune.threshold less by a mile if burn time a year or two classical music.HELP?anyone out there knows anything about this power amplifier.i am trying to buy the pair.
goingnuts
I've been told that the two different amps are based upon the same chasis etc.. Threshold was very conservative about their use of transistors, with only about 20% of total capability actually used. As was mentioned above, each unit had two very large trannies. Nelson Pass has written a paper which would agree with the "sweet spot" concern. Either asking Nelson Pass on his section of the DIYaudio.com site or speaking with ex Threshold tech Jon Soderberg at vintageamprepair.net would probably give the most difintive answers.
You could call Threshold Audio and see if they can help you. please see

http://www.threshold-audio.com/
Have the manual right here. Same # of per channel output transistors 64, same uF size power supply = huge .25 Fahrad (key is cap voltage rating), bias current almost identical 1.1-1.2 amps with the lower the 12e, same peak current output 200 amps (35 for the 1600e versus 70 for the 12e class A). This suggests to me that you can tap the transformer to change the voltage & I believe NP told me once it was possible for my S/550e. Ask him at diyaudio or ask Jon. If I saw one I'd buy a 12e but I think they're very rare and I've never seen a S1600e here.