ML22Q573-NNNMB Datasheet, PDF (26/66 Pages) List of Unclassifed Manufacturers – 4-Channel Mixing Speech Synthesis LSI

FEDL2257X-05
ML22Q573/ML2257X
Mixing Function
The ML22Q573/ML2257X can perform simultaneous mixing of four channels. It is possible to specify FADR,
PLAY, STOP, and CVOL for each channel separately.
• Precautions for Waveform Clamp at the Time of Channel Mixing
If channel mixing is done, the possibility of an occurrence of a clamp increases from the mixing calculation point
of view. If it is known beforehand that a clamp will occur, then adjust the sound volume of each channel using
the VOL command.
• Mixing of Different Sampling Frequency
It is not possible to perform channel mixing by a different sampling frequency group.
When performing channel mixing, the sampling frequency group of the first playback channel is selected.
Therefore, note that if channel mixing is performed by a sampling frequency group other than the selected
sampling frequency group, then the playback will not be of constant speed: some times faster and at other times
slower.
The available sampling groups for channel mixing by a different sampling frequency are listed below.
8.0 kHz, 16.0 Hz, 32.0 kHz … (Group 1)
12.0 kHz, 24.0 kHz, 48 kHz … (Group 2)
6.4 kHz, 12.8 kHz, 25.6 kHz … (Group 3)
Figures below show cases where a phrase is played at a sampling frequency belonging to a different sampling
frequency group.
fs＝16.0kHz
fs＝16.0kHz（Invalid、Will be played as fs＝12.8kHz）
Channel 1
Channel 2
fs＝25.6kHz
Figure 1 Case where a phrase is played at a sampling frequency belonging to a different
sampling frequency group during playback on channels 1 and 2
Channel 1
Channel 2
fs = 16.0 kHz
Played normally if not being played by
other channel.
fs = 25.6 kHz (Valid)
End of channel 1
Figure 2 Case where a phrase is played at a sampling frequency belonging to a different
sampling frequency group after playback is finished at the other channel
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