Sunfire IV User Manual

Page of 60
User's Manual
48
CHAPTER 5
The Holographic Image (also called 
"Sonic Holography") is a unique 
pro cess which enhances the three-
di men sion al effects and realism of 
stereo sound. This is modeled in DSP, 
from a design based on Bob's legend-
ary (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, a cymbal crashes, both your 
ears will hear it and the brain tells you 
accurately the position of the mu si cian. 
In a stereo recording of the concert, this 
cymbal crash will be heard from both 
speak ers. The left ear will hear the left 
speak er, which is fi ne, but it 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.
To summarize : 
1.   A real musical event will create 
only two direct sound arrivals, 
one at the left ear and one at 
the right. 
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.
The Holographic Image circuit was 
de signed to cancel out the unwanted 
second arrivals. The left ear will main-
ly hear the left speaker and the right 
ear mainly hears the right speaker. 
This 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 can-
cel 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 confi nes of the fl 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 the Holographic Image 
works by phase cancellation of the 
unwanted second sound arrivals, ac-
curate speaker positioning is required. 
You must 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 the 
next page to get the best results. This 
is the same as any standard stereo 
system, only with more care taken to 
position the left and right speakers 
accurately.
The Hologram circuit can be 
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.
Holographic Im age
Software CD
The TGIV Flash memory software 
can be upgraded by connecting 
your PC to the TGIV's RS-232 serial 
port, and downloading any avail-
able update fi les from our website: 
www.sunfi re.com. This is the preferred 
method, as the software can be up-
dated fairly quickly. See page 51 for 
more details.
Alternatively, the TGIV software 
can be upgraded using a CD avail-
able from Sunfi re Technical Support. 
This CD will be available periodically 
if there are major software changes 
since the initial release.
The following notes show the CD 
upgrade procedure. The CD or DVD 
player must be connected to the 
TGIV's digital audio inputs.
1.   Turn on your TV, your CD 
player and the TGIV.
2.   Use the TGIV remote to select 
the On Screen Display.
3.   Go to the Settings Menu and 
then select the Software Menu. 
4.   Select "Upgrade Software," 
which brings up a second OSD 
menu.
5.   On the TGIV, select the digital 
input which will play the CD. 
Press ENT on the remote (bot-
tom right).
6.   Press 1,2 and 3 on the remote, 
then play the CD. The TGIV 
display will show the status as 
the CD data is transferred into 
the TGIV.
7.   Turn off the TGIV when the 
software transfer is complete.
SOFTWARE
UPGRADE SOFTWARE
REVISION LIST