HDS-16/HRM-16 HEADPHONE DISTRIBUTION SYSTEM
This connector delivers the input signals and
power supply from the HDS-16 (parallel) or
from another HRM-16’s OUTPUT TO ADDI-
TIONAL HRM-16’s connector (series).
The remaining rear panel inputs and outputs
are ¼-inch TRS connectors.
EFFECTS SEND: Connect this mono output to
EFFECTS RETURN: Use the L input for a
mono return (panned center) or L and R inputs
LINE OUT: Use this mono, line-level output to
route the HRM-16 to a monitor system. The
LINE OUT and headphone signals are both
affected by the MASTER VOLUME and HI/LO
TALKBACK SWITCH REMOTE: Plug a mo-
mentary switch into this jack to use instead of
(or in ad di tion to) the TALK button.
This connector carries the same signal sent
to the INPUT FROM HDS-16 connector. Con-
nect this output to another HRM-16’s INPUT
FROM HDS-16 connector to achieve a series
con nec tion. An output that simply replicates the
input is often called input through because the
signal is sent out before being processed in
the device. As a result, the HRM-16’s top panel
controls do not affect the OUTPUT TO ADDI-
The head phone driver and power supply regu-
lators are protected against over-temperature
and current overloads. The regulated power
delivered from the HDS-16 to the HRM-16 is
protected against over-current by PolySwitch
resettable fuses inside each HRM-16. These
fuses prevent a defective HRM-16 from shut-
ting down the HDS-16 or attached HRM-16s.
Both devices reset au to mat i cal ly after clearing
the fault and removing power to the circuit.
The regulated power delivered from the HDS-
16 to the HRM-16 is protected against shorted
cables by an over-current crowbar circuit. The
affected power supply turns off in response
to an over-current condition. Restore normal
operation by removing the defective cable or
HRM-16 and turn off the power to the HDS-16
The AC-line fuse is a 1-Amp Slo-Blo. Replace
it only with a fuse of the same type and rating.
Table 1: Centronics cable losses per 100 feet
