Sunfire TGR401 - Manual (Page 45)

User's Manual
45
CHAPTER 5
Sonic Holography is a unique
pro cess which enhances the three-
di men sion al effects and realism of
stereo sound. This is from a design
based on Bob Carver's legendary
(and much sought after) Carver C-9
Sonic Holography Generator.
This circuit was designed to over-
come a problem in ob tain ing accurate
sound re pro duc tion:
In a stereo system, both ears will
hear the output from both speakers.
The left ear hears sound from the left
speaker and from the right speaker.
To see a problem with this, compare
what happens when listening to a live
musical performance:
During a concert, each ear will
receive one direct sound arrival. For
ex am ple, both ears will hear the piano
playing, and your brain tells you ac-
curately the position of the mu si cian. In
a stereo recording of the concert, this
piano will be heard from both speak ers.
The left ear will hear the left speak er,
which is ¿ ne, but the left ear will also
hear the crash from the right speaker.
These extra sounds tend to confuse the
sense of sound source location.
The stereo effect in a good pair of
head phones is enhanced because the
left ear only hears the left head phone,
and the right ear hears only the right
headphone. There are no extra sound
arrivals.
Sonic Holography
To summarize :
1. A real musical event will create
only two direct sound arrivals,
one at the left ear and one at
the right. We can accurately
judge the depth and positioning
of the piano on stage.
2. Stereo playback will give four
arrivals, as both speakers
are heard by each ear. These
second sound arrivals reduce
our naturally accurate sense of
positioning.
3. Sonic Holography cancels out
the unwanted second arrivals.
The left ear mainly hears the
left speaker and the right ear
mainly hears the right speaker.
The depth and positioning cues
are restored.
Sonic Holography is accomplished
by send ing a complex crosstalk signal
from the left and right speakers in
addition to the normal program. These
extra signals are virtually identical to
the unwanted second sound arrivals
but they are out-of-phase with them
and they cancel each other out.
The result is a more three-di men -
sion al and wider soundstage, where
the positioning clues are restored. In
a way, the musicians have been freed
from the con¿ nes of the À at plane be-
tween the speak ers. You will per ceive
them as playing forward or playing
behind the speakers or to one side
or the other, not just somewhere in
between. We recommend that you ex-
periment with its effect, remember that
you are listening for a more accurate
sense of the location of the different
musicians.
Because Sonic Holography works
by phase cancellation of the unwanted
second sound arrivals, accurate
speaker positioning is required. Make
sure that the left speak er is the same
distance away from you as the right
speaker. Follow the front speaker
place ment on page 46 to get the best
results. This is the same as any stan-
dard stereo system, only with more
care taken to position the left and right
speakers accurately.
Sonic Holography is engaged using
the remote control or from the front
panel. There is a short mute period
until the circuit is fully engaged or
dis en gaged.
1. Press the remote's MAIN button a
few times to reach the main menu.
2. Press TG401 to set the remote to
operate the TGR-401.
3. Press PAGE twice to
reach page 3.
HOL ON and OFF
allow you to turn the
Holography on or off.
stage
stage