AKG SURROUND TECHNOLOGY
A Harman International Company.
➝Dolby Surround
These four channels are encoded by a special circuit and recorded in “piggy- back” fashion on the two stereo tracks. This allows the signal to be reproduced in mono, stereo, or (using a decoder) through four separate channels. For sur- round reproduction, the signal needs to be decoded. This is the job of the Dolby Surround decoder.
➝Dolby Digital decoder
The digital
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DOLBY SURROUND
P R O • L O G I C
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➝IVA processing
Patented AKG IVA processing for spa- tial sound is the heart of each HEARO surround headphone system. IVA pro- vides natural (binaural) imaging through headphones in a similar way as if you were listening to a pair or loudspeak- ers.
Binaural sound |
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A: Sound waves from a given source |
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arrive at one ear earlier than they do at |
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the other, and they “look” different, too. |
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Amplitude and phase shifts allow us to |
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localize a sound source in space. |
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B: Headphones usually eliminate | A |
these important amplitude and phase | |
shifts. Sound sources are perceived as |
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being inside the head rather than in the |
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room. |
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C:IVA processing developed by AKG adds to a stereo signal the amplitude and phase shifts that are necessary to create a sense of natural, spatial, “out-
side the head” imaging. | B |
In short, IVA processing provides a per- fectly natural, spatial (binaural) sound through headphones.
➝Digital transmission
Digital transmission ensures pristine
Inc.,
processed in the digital domain by IVA without any degradation of sound qual-
DOLBY
®
surround sound with a
are trademarks of Dolby Laboratories Licencing Corporation. Logic7 and the Logic7 Logo are registered trademarks of Lexicon,
ity.
➝LOGIC7 decoder
Up to now, the latest development by the innovative engineers at LEXICON was only used in
The LOGIC7 decoder automatically identifies the input signal as mono, stereo, or surround encoded and processes the signals appropriately.
The LOGIC7 decoder uses the localiza- tion cues contained in stereo signals to generate a
Along with the standard 5.1 surround format, LOGIC7 also provides left and right side channels, for a total of seven loudspeaker channels plus one sub- woofer channel.
In addition, another surround center channel is added in the headphone mode. In conjunction with IVA process-
D I G I T A L
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Digital radio links are immune to inter-
ference and “jamming” from devices emitting RF radiation such as TV sets or computers.
➝
➝Ear matching curves
Sound waves from a given source arrive at one ear earlier than they do at the other, (see also “IVA processing”, para A) because the head, trunk, and ears cause amplitude and phase shifts. All these changes can be illustrated by
➝Digital antenna diversity
Diversity reception is normally used in professional wireless micro- phone systems to ensure perfect reception even under extremely dif- ficult conditions. An adaptive algorithm makes sure the antenna that delivers the better signal is always active to prevent dropouts.
➝VMAx
VMAx provides surround sound from a pair of stereo loudspeakers, with no
extra hardware. All you need is aVMA
“Dolby”, the
ing, LOGIC7 provides its full perform- ance level with eight virtual loudspeak- ers.
The result is far more natural and accu- rate imaging.
stereo amplifier and speakers. The VMAx processor simulates the en- velopment of surround sound.
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