Two buttons for everything
The two precision buttons
with clear feedback,
perform all functions of the LE 03

Use the HP key to adjust the volume
for the headphones.

If you keep the button pressed,

the volume changes continuously, 

from loud to quiet and vice versa.
A break of 3 seconds changes direction.
If the button is pressed every second,
the volume changes in 1dB steps.
A break of 3 seconds changes direction.

The last setting is saved.

Use the DO key to change the

output level for DIG OUT and USB
If you keep the button pressed, the level changes continuously from
plus to minus and vice versa.
A break of 3 seconds
changes direction.
If the button is pressed every second,
the level changes in 1dB steps.
A break of 3 seconds changes direction.

The last setting is saved.

If you press both buttons at the same time
the digitized input signal is switched

on / off on the headphones.

Mono Mode
If you hold down the HP button while plugging in the USB cable, the LE 03 is in mono mode.

The LED is on.
The left analog input is the mono input.
The mono signal is audible on the left and right of the headphones and the digital outputs.

1KHz Ref Generator
If you hold down the DO button while plugging in the USB cable, the
1KHz Ref Generator is switched on.

The LED flashes.
At the DIG OUT and the USB Out
there is a precise
1KHz -9dBFS signal.

If you press the DO button again the generator is off.