Yamaha Pocket Miku User Manual page 13

 If your device is out of tune
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Execute "tuning command" and calibrate the carbon keyboard.
To ensure that the notes and characters that Pocket Miku sings are consistent,
an internal program monitors the electrical conditions of the carbon keyboard
while the device is on. However, many factors, such as scratches and stains on
the carbon keyboard, the condition of the power source, and moisture in the
atmosphere may cause instability in the pitch and pronunciation. You may also
find that the pitches produced while playing in "do re mi" mode do not match
the corresponding position on the keyboard. Execute "tuning command" to
fix this condition. "Tuning command" reexamines the voltage condition of the
carbon keyboard and corrects its positions to their corresponding pitches. To
execute "tuning command, " press the [O] button while holding down [volume
up] and [volume down] simultaneously. A beeping sound will be heard,
confirming that the command has been executed. After executing "tuning
command, " the carbon keyboard will switch to calibrate mode, and the LED
will flicker. Touch each key from one end of the carbon keyboard to the other
using your stylus at least once. After touching every key, the LED will stop
flickering, indicating that you have finished tuning.
Concerning NSX-1 application compatibility mode
Although Pocket Miku is equipped with the sound chip NSX-1, by
default it will not receive CC or SysEx for NSX-1's character data. If
NSX-1 receives MIDI data or applications that use CC or SysEx character
data, it will not produce action or sound intended by the data's author.
When you want to use MIDI data or the application for NSX-1, hold
the "Volume up" and "Volume down" buttons simultaneously, then
press [U] in order to turn on "NSX-1 application compatibility mode. "
A beeping sound will be heard, confirming that compatibility mode
has been switched on. Pressing the same combination of buttons
again will produce another confirmation sound, indicating that NSX-1
application compatibility mode has been switched off, and the device
will no longer receive commands for NSX-1.
* When "NSX-1 application compatibility mode" is turned on, Pocket Miku's character sound table data, and by
extension the contents of the [A] to [O] buttons and the preset lyrics, will be overwritten. To restore Pocket Miku to its
original condition, execute either the "panic command" or the "initialize command. " (See page 12.)
For a more detailed user guide, please refer to http://otonanokagaku.net/nsx39/
Press simultaneously
Press simultaneously
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