Sunfire architectural choice series ii User Manual

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User's Manual
Introduction
Dear Friend:
    Thank you for purchasing my 
Sunfire Architect’s Choice Series II  two channel power
amplifier. I hope you enjoy it and the music it makes as much as I have enjoyed creating it for you.
This magnificent amplifier represents my very latest thinking - and my best amplifier design
ever. I’ve spent over twenty years developing it, and cannot imagine how I could make it any
better, or refine it any further. No matter what, its performance is, at first, somewhat difficult to
believe.
The 
Sunfire Signature Edition can produce 625 watts rms per channel into 8 ohms and
1250 watts rms into 4 ohms.
The 
Sunfire Standard Edition can produce 325 watts rms per channel into 8 ohms, and 650
watts rms per channel into 4 ohms.
The big breakthrough feature of the 
Sunfire Amplifier is its uncanny tracking downconverter,
which uses 18 Herculean Mosfets in the Signature Edition and 12 in the Standard Edition.
The circuit boards are heavy glass epoxy, double sided, with a Faraday shield on the back
side. All resistors in the signal path are 1% tolerance, metal-film. Critical capacitors are film
devices with high dielectric strength and ultra low absorption characteristics. An enormous 
Sunfire
power source built around a massive power transformer provides the ultimate muscle for limitless
dynamics.
I could go on and on, but here’s the best part: I’ve included two kinds of left and right outputs:
(1) a standard voltage-source (i.e., near zero impedance) output for all typical applications and
(2) a higher-impedance current-source output, which many prefer for electrostatic, planar mag-
netic, or ribbon speakers. Or you can biwire your system with the voltage source driving the
woofer(s) and the current source driving the upper part of the system. In many cases this provides
by far the best possible interface between the amplifier and the speaker system.
Whichever way you decide to hook up the
 Sunfire power amplifier, it will create a multilayered
soundstage that is deep, wide, three-dimensional, and utterly believable. The optional current-
source output can coax forth a sensuous, delicately detailed musical voice long associated with
low-powered classic tube amplifiers. (The current-source characteristic of vacuum tubes is the
dominant factor in the soundstage delivery of classic tube amplifiers).
Bob Carver, Amplifier Designer, Physicist
Introduction