Sunfire TGR401 User Manual

Page of 69
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  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