VS1033C Datasheet, PDF (32/74 Pages) List of Unclassifed Manufacturers – MP3/AAC/WMA/MIDI AUDIO CODEC

VLSI
Solution ^y
VS1033c PRELIMINARY
VS1033C
8. FUNCTIONAL DESCRIPTION
8.4 EarSpeaker Spatial Processing
While listening to the headphones the sound has a tendency to be localized inside the head. The sound
field becomes flat and lacking the sensation of dimensions. This is unnatural, awkward and sometimes
even disturbing situation. This phenomenon is often referred in literature as ‘lateralization’, meaning
’in-the-head’ localization. Long-term listening to lateralized sound may lead to listening fatigue.
All real-life sound sources are external, leaving traces to the acoustic wavefront that arrives to the ear
drums. From these traces, the auditory system in the brain is able to judge the distance and angle of each
sound source. In loudspeaker listening the sound is external and these traces are available. In headphone
listening these traces are missing or ambiguous.
The EarSpeaker processing makes listening via headphones more like listening the same music from
real loudspeakers or live music. Once the EarSpeaker processing is activated, the instruments are moved
from inside to the outside of the head, making it easier to separate the different instruments (see figure
13). The listening experience becomes more natural and pleasant, and the stereo image is sharper as the
instruments are widely on front of the listener instead of being inside the head.
Figure 13: EarSpeaker externalized sound sources vs. normal inside-the-head sound
Note that EarSpeaker differs from any common spatial processing effects, such as echo, reverb, or bass
boost. EarSpeaker simulates accurately human auditory model and real listening environment acoustics.
Thus is does not change the tonal character of the music by introducing artificial effects.
EarSpeaker processing can be parameterized to a few different modes, each simulating a little different
type of acoustical situation and suiting for different personal preference and type of recording. See
section 8.7.1 for how to activate different modes.
• Off: Best option when listening through loudspeakers or if the audio to be played contains binaural
preprocessing
• minimal: Suits well for listening to normal musical scores with headphones, very subtle
• normal: Suits well for listening to normal musical scores with headphones, moves sound source
farther than minimal
• extreme: Suits well for old or ’dry’ recordings, or if the audio to be played is artificial, for example
generated MIDI
Version 0.9, 2006-08-15
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