Rich Musical Ringtones - 40 Voices; Combined Wavetable And Fm Sound Synthesis - Sony Ericsson J200 White Paper

Rich musical ringtones – 40 voices
The human ear can perceive sounds from approxi-
mately 20 Hz up to 20 kHz. In most GSM mobile
phones, the speech sound range is from 300 Hz to
3400 Hz, which is good enough for speaking, but
quite poor for music. The J200 can handle up to
more than 20 kHz, which means excellent sound
quality.
The J200 has a dedicated speaker for ringtones
and sounds, to ensure the best possible sound
quality. This speaker is situated on the side of the
phone, ensuring that no discomfort is felt if a sec-
ond call is received during an ongoing call.

Combined wavetable and FM sound synthesis

Sony Ericsson has chosen to implement a combi-
nation of Wavetable (8 voices) and FM synthesis
(32 voices), which consists of sampled real instru-
ments (mainly percussion sounds) and generated
synthetic tones.
The quality of the sound heard from the speakers
depends on many different things, for example on
the synthesizer, the amplifier, or the speakers. An
important factor for sound quality is the number of
voices. The human ear cannot separate each voice
if the number of voices increases above 16 or so,
because then the voices merge together. But the
nuances in music increase, and the music is expe-
rienced as more sophisticated if the number of
voices increases. Many modern sound modules in
synthesizers used by musicians have 16, 24 or 32
note polyphony. The number of voices used in the
J200 is 40, which gives rich musical ringtones.
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J200
White Paper
November 2004