Sound Impressions
Because this is an AC-3 enabled system, we decided
to cover the sound impressions without even attempting a PC hook-up. We used
a stand-alone Dvd Player for the complete testing and impressions. Our DVD
player of choice was Sony’s DVP-S7700 Player, which currently stands at the
very top of Sony’s DVD product line. The movie of choice was The Matrix.
Once the unit was connected via the Optical S/PDIF
port, the decoder auto-detected the Dolby Digital (AC-3) mode and we were
ready to proceed. We used the DVD player to work on the complete impression
chapter. For the Dolby PRO LOGIC mode, we used a normal Stereo RCA cable.
The Satellites sounded great at medium volumes;
the highs were precise and crisp. At higher volume levels some minor distortion
was noticed. At maximum volume levels the distortion was becoming increasingly
present, in some scenes it was masked because of the high bass output. The
Mid-range units were also doing a great job on the sound enhancements. Getting
back to the distortion, it shouldn’t affect many people because it was present
in the 100dB ranges. 100 dB is a reasonably high volume level that not a lot
of people will use in the little rooms this system is meant for.
The decibel (abbreviated as dB, and also as
dB and DB) is a common unit of measurement for the relative loudness of a
sound or, in electronics, for the relative difference between two power levels.
A decibel is one-tenth of a "Bell", a seldom-used unit named for Alexander
Graham Bell, inventor of the telephone. In sound, the difference between two
sound levels is ten times the common logarithm of the ratio of their power
levels. Decibels measure a scale from the threshold of human hearing, 0 dB,
upward towards the threshold of pain, about 120-140 dB.
As examples: the sound level in the average
residential home is about 55 dB, average conversation is about 75 dB, typical
home music listening levels are about 90 dB, a loud rock band about 110 dB,
and a jet engine close up is 150dB. Decibel units are commonly used in audio
equalizers, both the hardware kind and the software kind, as a convenient
reference point while editing. Boosting an equalizer band whose center point
is 1000 Hz by 3 dB means that you have raised the volume level of that frequency
band by 3 dB as it relates to the other frequencies in the sound. A typical
equalizer has a range for boosting or diminishing a sound level of +/-18 dB.
The AC-3 mode was definitely the top choice for
movies encoded in Dolby digital. The effects were traveling across the five
speakers; gun shots in the back, explosions in the front channels. It was
really that live feeling you feel, as you were in a theater or present in
the movie scenes. The Subwoofer was also doing an outstanding job for its
25w-output rating.
The PRO LOGIC that uses four direct channels
was a pleasant experience, but not comparable to Dolby Digital. Effects were
still present in the test but at a much lower level than in the AC-3 mode.
The Subwoofer was doing a great job in the PRO LOGIC mode too. Because of
the little response of the rear channels that starts at around 100Hz, you
will here a clear difference between explosions in the mono surround channel
compared to the front channels.
The AC-3 mode is definitely the top their choice
for movie theater setups, the PRO LOGIC days are now starting to end. The
introduction of the AC-3 mode can be compared to the maturation of the old
sound days: as moving from mono to stereo technology.
