Sennheiser HE 1 User Manual page 27

Putting the HE 1 into operation | Connecting the headphone tube amplifier to a power amplifier or to active loudspeakers
A
B
Connection possibility of the audio device: analog, XLR-3, balanced
BAL
ORPHEUS
Connection cables: 2 balanced XLR-3 cables
Connection possibility of the audio device: analog, RCA, unbalanced
UNBAL
ORPHEUS
Connection cable: stereo audio cable with 2 RCA connectors at each end
L
R L
L R
R
L R
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