Gryphon Colosseum - Manual (Page 13)

Class A, so we repeat with no
apologies: TRUE PURE CLASS A
means heavy transformers, very
large heatsinks, lots of heat, lots of
electricity, expensive parts and
costly assembly.
While we appreciate and endorse
every effort to conserve energy and
preserve our global resources, our
research into efforts to obtain Class
A performance from class A/B
topologies makes it clear that there
simply is no substitute for the sheer
magic of pure class A.
However, based on thorough analy-
sis of typical listening situations, we
have devised Green bias (green for
reduced environmental impact).
Green bias offers TRUE, PURE
CLASS A with considerably lower
power consumption than the tradi-
tional solution.
With the DM100, Gryphon was the
first amplifier manufacturer ever to
offer programmable Class A bias as
a means of reducing power con-
sumption without compromising
Class A performance.
Green bias in the Gryphon
Colosseum allows the user to
select the amount of Class A at any
given time, taking into account such
factors as speaker sensitivity, room
size , musical dynamics and overall
volume level.
Green bias improves on our pro-
grammable bias by giving the fortu-
nate owners of a Gryphon pream-
plifier the option of letting the pre-
amplifier automatically control the
bias.
Instead of a conventional poten-
tiometer, the Gryphon Mirage and
Sonata employs a attenuator type
technology, which can be used to
select the bias to match the overall
playback level, thus ensuring pure
Class A at all times.
Unlike signal-sensing "auto-biasing
systems" Green bias does not
attempt to follow the signal at all,
the current selection of the volume
control determines the bias setting
whether music is playing or not. In
effect, this means that if the user
selects, for instance, position 11
( Sonata Allegro ) on the volume
control, then the bias will increase
to 100% (High Bias) producing 150
Watts pure Class A. This bias level
will be maintained even when music
is absent or when the amplifier or
preamp is muted. If the user turns
the volume control down below
position 10, the Preamplifier will
automatically instruct the amplifier
to reduce bias to 50 watts of pure
Class A.
Bias low is selected manually from
the top panel. To leave low bias
,you must select mid or high bias on
the top panel.
If Green bias is activated, in the dis-
play manu and the amplifier will
automatically adjus bias to match
the postion of the preamp volume
control.
While Green bias does not offer the