ADP 303 (serv.man3) - Harman Kardon Audio User Guide / Operation Manual. Page 4

Introduction and Safety Information

So far we have mentioned five channels,
yet Dolby Digital is a six channel system.
You may have also heard this system
referred to as “5.1” channel audio.
Where, you may ask, is the sixth
channel, and what is the “.1” channel? 

The answer is simple. The sixth channel
is a special low frequency effects channel,
or “LFE”. This is the bass channel that
sends the thunder of explosions and
other effects to your subwoofer.

It is separate from the other five
channels, brining the total channel
count to six. This is true even though the
“sixth” channel is non-directional, as
opposed to the highly directional nature
of the other signals. The reason for the
“.1” designation is that the LFE channel
is bandwidth limited. By definition, the
LFE channel has a restricted bandwidth,
while the others are full range. Thus, the
system’s inventors decided that although
they could call Dolby Digital a six
channel system, since there are six
separate channels, it is more properly five
“full” channels plus one separate, but
limited channel. 

In this case, “5.1” equals six!

■

High quality Dolby Digital decoding
chip, manufactured by Zoran.

■

AC-3 RF input, for connection to
compatible laser disc players with AC-3
RF output.

■

Coax and Optical Digital AC-3 inputs,
for connection to other sources, such
as DVD and/or DSS.

■

Individual channel level controls and
internal test tone generator, for precise
system setup. 

■

Master volume control and mute
function.

■

Adjustable delay time.

■

Bypass feature.

■

Rear panel speaker configuration
switches to match the ADP303 to a
wide range of speaker types and sizes. 

■

6 discrete channel inputs and outputs,
for connection between existing
surround sound pre-amp/processors
and power amplifiers, featuring RCA
jacks for full compatibility with high
quality A/V cables.

■

Dolby Digital AC-3 indicator light,
shows the presence of AC-3 coding.

3

In order to help you use this manual and
make the proper system connections,
certain conventions appear throughout
the manual.

å

– (letter in a circle) indicates a

specific front panel control

¡

– (number in a circle) indicates a

rear panel connection

– (number in a triangle) 

indicates a specific step in the
installation instructions

24093_ADP 303 Eng.  27/02/1998 10:34  Side 4