User's Manual
4
CHAPTER 1
Dear Friend,
Thank you for purchasing a
Sun
fi
re Theater Grand Ampli
fi
er
. We hope you enjoy it and the music it
makes as much as we have enjoyed creating it for you.
The
TGA-7400
can pro duce
400 watts rms per channel into 8 ohms
and
800 watts rms into 4
ohms
.
The
TGA-7200
can pro duce
200 watts rms per channel into 8 ohms,
and
400 watts rms into 4
ohms
.
The big breakthrough is the uncanny tracking downconverter, which uses 18 Herculean Mosfets
in the TGA-7400 and the TGA-7200. This allows the ampli
fi
er to produce phenominal power output,
without the heat generated by conventional designs.
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-
fi
lm. Critical ca pac i tors are
fi
lm devices with high
dielectric strength and ultra low absorption characteristics. An enor mous power source built around a
massive power transformer provides the ultimate muscle for limitless dynamics.
We could go on and on, but here’s the best part: we’ve included two kinds of outputs on the
front
left
and
front right
channels:
(1) a standard
voltage-source
(i.e., near zero im ped ance) output for all typical applications and:
(2) a higher-impedance
current-source
output, which many prefer for electrostatic, planar
mag net ic, 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 in ter face between the ampli
fi
er and the speaker system.
Whichever way you decide to hook up the ampli
fi
er, it will create a multilayered sound stage that is
deep, wide, three-di men sion al, and utterly be liev able. The optional cur rent-source output can coax
forth a sen su ous, delicately detailed musical voice long associated with low-powered classic tube
ampli
fi
ers. (The current-source char ac ter is tic of vacuum tubes is the dominant factor in the sound-
stage delivery of classic tube ampli
fi
ers).
Bob Carv er, Ampli
fi
er De sign er, Physicist
Introduction
