Tuning A Musical Instrument - Tascam DR-40 Reference Manual

Tuning a musical instrument

1 Open the TUNER screen, and sound a note near the unit.
2 Tune the instrument so that the target pitch name
appears and the center of the tuner lights.
Bars appear to the left if the pitch is lower than the target
or to the right if higher. The bars increase as the pitch shifts
away from the target.
NOTE
The tuner can only be used with the built-in mics.
10 – Tuning a Musical Instrument (Tuner)
93
TASCAM DR-40