Sennheiser Set 820 Instruction Manual page 40

Additional information for hearing aid acousticians
Adjusting the earbow pressure
Loosen the screw at the rear of the stethoset receiver.
Move the screw in the long hole to the desired position
(continuously adjustable).
1 = Low earbow pressure
2 = High earbow pressure
Tighten the screw.
Adjustments for hearing disabilities
Turn the operating control fully counterclockwise (0). Remove
the operating control by carefully lifting it over the "guide
notch" on the inside. Use the 4 potentiometers on the circuit
board to individually adjust the max. volume and the bass
response for the left and right headphone system.
1
2
Bass response L
Bass response R
Max. volume L Max. volume R
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