Philips MX920AHT-37 - Manual (Page 36)

G lossary
A/V Inputs:
Allow injection of AfV signals, isolated from one another, to TV
receivers, VCRs, camcorders, and combis through discreet channels by
passing through the mner and other RF circuitry.
Balance:
Adjusts the relative volume levels of left and rights channels for optimal
stereo effect. Compensates for channel imbalance and non-symmetrical
loudspeaker positioning.
Bass:
The lower range of audio frequencies, up to approximately 500Hz.
Decibel (dB):
The minimum change in sound intensity that a human ear can distinguish.
A doubling of volume is a lOdB increase. To double volume in a stereo
system, a 10-fold increase in power output (WATTS) is required.
Dolby Pro-Logic® Surround Sound:
A movie or other source with audio encoded in Dolby Pro-Logic® creates
a very realistic soundfield-much like you would experience if you were
actually in the movie yourself. There are four components to this
soundfield: Front Left Channel (one speaker). Front Center Channel (one
speaker). Front Right Channel (one speaker), and Rear Channel (two
speakers placed to the left and right rear). The front center channel
contains mostly dialogue and center sound effects. The dialogue and
sound effects are therefor reproduced exactly where they should be-the
very center of the soundfield above or below the television, or through the
center speaker via a center channel output from the receiver. The front left
and rights speakers contain directional sounds (like a car going from left
to right across the screen) as well as other important effects that help
“steer” the audio more realistically to the listener’s ears. The rear speakers
help to re-create the reflective ambience of the original room in which the
audio was recorded. They generate short echos and delays that help make
the entire audio experience more lifelike.
Dolby® 3-Chauuel:
Dolby® 3-Channel operates like Dolby Pro-Logic© except in the Dolby®
3-Channel rear speakers are not used. Dolby® 3-Channel is usually
included on Dolby Pro-Logic® receivers for users who wish to wait to
buy rear speakers or for those whose home theatre environment is too
small to accommodate rear speakers.
Frequency:
In musical terminology, frequency generally refers to the pitch of a sound.
The frequency of a sound is measured in cycles per second (hertz). One
cycle is one complete audio waveform. Bass frequencies have a lower
number of waveforms (or cycles) per second, and treble frequencies have
a very high number of waveforms (or cycles) per second.
Frequency Response:
The frequency range in which an electronic component can accurately
reproduce its input. Humans can hear from 20Hz to 20,000Hz (20KHz).
An ideal component would have a Frequency Response, totally flat or
without any deviation, from 20Hz to 20KHz. Frequency Response
specifications are measured in db based on how closely a component’s
response resembles that of the ideal.
Graphic Equalizer:
Tone control device that cuts or boosts different frequencies within the
audio band. A graphic equalizer provides greater control over tone than a
single-knob tone control.
Hertz (Hz):
The basic unit of measure of frequency. One hertz equals one cycle
per second.
L/R Audio:
This abbreviation stands for Left and Right Audio.
Ohm:
A unit of electrical resistance or impedance calculated by dividing the
voltage applied to a circuit by the current (amperes) flowing in it. The
higher the number, the higher the resistance or impedance.
Signal-to-Noise Ratio:
The ratio, measured in decibels, between the ma.xlmum signal level and
the noise level with no signal present. The higher the value, the better the
sound reproduction.
Surround Output Level:
One select Dolby Pro-Logic® A/V receivers, this feature allow s you to
adjust the rear speaker level relative to the front speaker level according to
your viewing location and individual preference.
Surround Sound:
A system of audio reproduction that uses four or more speakers to
simulate the full three-dimensional effect of a live musical performance or
cinematic environment. (See also Dolby Pro-Logic® Surround Sound.)
Test Tone:
Dolby Pro-Logic® Surround Sound receivers offer this feature to allow
individual adjustment of all four channels (Left, Center, Right, and Rear)
according to your viewing location and individual preference. To set the
balance, a test tone is sent to each chaimel in a repeating cycle.
Total Harmonic Distortion (THD):
A measure of the distortion produced in an audio system as a result of the
production, within the system, of harmonics or multiples of the original
audio signal.
limer:
A radio receiver without amplification.
Wow and Flutter:
Audible periodic variations in the pitch of a sound from the audio system.
The low-frequency variations (up to about lOHz) are wow, while the
higher-frequency variations are flutter.
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