Datasheet

VS1053b Datasheet
9 FUNCTIONAL DESCRIPTION
9.3 EarSpeaker Spatial Processing
While listening to 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 an unnatural, awk-
ward 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 of 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.
EarSpeaker processes sound to make listening via headphones more like listening to the same
music from real loudspeakers or live music. Once 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 17). 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 17: 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 accurately simulates the 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, suiting different personal preferences and types of record-
ing. See section 9.6.1 for how to activate different modes.
• Off: Best option when listening through loudspeakers or if the audio to be played contains
binaural preprocessing.
• minimal: Suited for listening to normal musical scores with headphones, very subtle.
Version: 1.22, 2014-12-19 35