Krell Phantom Manual - Manual (Page 6)

6
SECTION
ONE
Phantom Features and Technology
This section describes the innovative features and technology of the Phantom pre-
amplifier, and defines CAST and other key terms used in this reference.
The Phantom Stereo Preamplifier, evolving from the flagship Evolution Two, works
to carefully transmit audio signals without damaging the ephemeral staging and
dimensional components of the music. The Phantom is a two chassis design with
a separate power supply that isolates the critical audio stages for the lowest pos-
sible noise floor. A combination of advanced technologies and inspired design ele-
vate the Phantom preamplifier’s performance to the reference level.
Features
Preamplifier
The Phantom preamplifier is the first Krell amplifier to include an optional
crossover. The crossover fuctionality offers the ability to use a subwoofer/satellite
speaker arrangement and still maintain the highest quality sonic performance.
Previous to the Phantom preamplifier, this system configuration would require sig-
nals to pass through a subwoofer’s lower quality crossover circuitry. The Phantom
preamplifier is the centerpiece of a world class audio system where space is at a
premium.
Crossover Highlights
Owing to Krell’s work in the Modulari Duo Reference loudspeakers, the unique
crossover feature is a highly sophisticated option. When the optional board is
present, additional crossover menu items become available. Definable parameters
include independently assignable crossover frequencies and filter types for te high
and low pass sections. Choices include 40Hz, 55Hz, 75Hz, and 100Hz crossover
points with 12dB, 18dB, and 24dB Butterworth or 24dB Linkwitz-Riley style filters.
The high pass section of the crossover uses the full Phantom preamplifier circuitry
for its ouput stage.
Circuitry Highlights
The Phantom preamplifier is a dual monaural circuit design with the left and right
channels afforded their own power supply regulation and individual full chassis
sized boards. All signal gain is realized in surface mount topology using propri-
etary multiple-output current mirrors with nearly 500 times the open loop linearity
of other designs. Approaching 1 MHz of open loop bandwidth in a zero feedback,
balanced, Krell Current Mode, the Phantom output stage terminates in Krell CAST.
continued