Yamaha RX-V2500 Manual Do Proprietário

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GLOSSARY
ADDITIONAL 
INFO
RMA
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IO
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ITU-R
ITU-R is the radio communication sector of the ITU 
(International Telecommunication Union). ITU-R 
recommends a standard speaker placement which is used 
in many critical listening rooms, such as mastering 
studios.
LFE 0.1 channel
This channel is for the reproduction of low bass signals. 
The frequency range for this channel is 20 Hz to 120 Hz. 
This channel is counted as 0.1 because it only enforces a 
low frequency range compared to the full-range 
reproduced by the other 5/6 channels in Dolby Digital or 
DTS 5.1/6.1-channel systems.
Sampling frequency and number of 
quantized bits
When digitizing an analog audio signal, the number of 
times the signal is sampled per second is called the 
sampling frequency, while the degree of fineness when 
converting the sound level into a numeric value is called 
the number of quantized bits.
The range of rates that can be played back is determined 
based on the sampling rate, while the dynamic range 
representing the sound level difference is determined by 
the number of quantized bits. In principle, the higher the 
sampling frequency, the wider the range of frequencies 
that can be played back, and the higher the number of 
quantized bits, the more finely the sound level can be 
reproduced.
THX Cinema processing
THX is an exclusive set of standards and technologies 
established by the world-renowned film production 
company, Lucasfilm Ltd. THX grew from George Lucas’ 
personal desire to make your experience of the film 
soundtrack, in both movie theatres and in your home 
theatre, as faithful as possible to what the director 
intended.
Movie soundtracks are mixed in special movie theatres 
called dubbing stages and are designed to be played back 
in movie theatres with similar equipment and conditions. 
This same soundtrack is then transferred directly onto 
Laserdisc, VHS tape, DVD, etc., and is not changed for 
playback in a small home theatre environment.
THX engineers developed patented technologies to 
accurately translate the sound from the movie theatre 
environment into the home, correcting the tonal and 
spatial errors that occur. On this product, when the THX 
indicator is on, THX features are automatically added in 
Cinema modes (e.g. THX Cinema, THX Surround EX).
Adaptive decorrelation 
In a movie theatre, a large number of surround speakers 
help create an enveloping surround sound experience, but 
in a home theatre there are usually only two speakers. This 
can make the surround speakers sound like headphones 
that lack spaciousness and envelopment. The surround 
sounds will also collapse into the closest speaker as you 
move away from the middle seating position. Adaptive 
decorrelation slightly changes one surround channel's time 
and phase relationship with respect to the other surround 
channel. This expands the listening position and creates – 
with only two speakers – the same spacious surround 
experience as in a movie theatre.
Re-equalization 
The tonal balance of a film soundtrack will be excessively 
bright and harsh when played back over audio equipment 
in the home because film soundtracks were designed to be 
played back in large movie theatres using very different 
professional equipment. Re-equalization restores the 
correct tonal balance for watching a movie soundtrack in a 
small home environment.
Timbre matching
The human ear changes our perception of sound 
depending on the direction from which it is coming. In a 
movie theatre, there is an array of surround speakers so 
that the surround information is all around you. In a home 
theatre, you use only two speakers located to the side of 
your head. The timbre matching feature filters the 
information going to the surround speakers so that they 
more closely match the tonal characteristics of the sound 
coming from the front speakers. This ensures seamless 
panning between the front and surround speakers.
Audio information
00_RX-V2500U_EN.book  Page 99  Friday, August 20, 2004  5:20 PM