Maico MA 27 Operation Manual page 21

Operation Manual MA 27 / MA 27e
Eliminate any obstructions which will interfere with the
placement of the earphone cushions on the ear (i.e. hair,
eyeglasses).
Ensure that the headphones are positioned correctly: red side
on the right ear, blue side on the left ear. Adjust the headband
of the headphones so that the earphones are positioned at the
correct height (i.e. the sound output grid exactly facing the ear
canal).
Prior to hearing threshold level measurements, the following
instructions should be given. "You will now hear a variety of
tones with various loudness levels. Please push the response
switch when you hear a tone and release the button when you
no longer hear it."
8104818 Rev.2.0 17 04/16