Box-Design Pro-Ject Head Box RS User manual

INSTRUCTIONS FOR USE
Pro-Ject Head Box RS

© Pro-Ject Audio Systems · Pro-Ject Head Box RS · Revision 2014.6.17
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Dear music lover,
thank you for purchasing a Pro-Ject Audio Systems headphone amplifier.
In order to achieve maximum performance and reliability you should study these instructions for use carefully.
Warning of a hazard for the user, the unit or possible misuse.
Important notice.
Safety instructions
AC outlet voltages vary from country to country. Before connecting to the mains, make sure that the
voltage in your area meets the voltage requirements printed on the power supply.
The power supply is used to connect/disconnect the unit from the mains. Make sure that the power
supply is easily accessible at all times. Never handle the device, the power supply while your hands are
wet or damp.
Avoid letting liquids enter the device or the power supply. Never place any item containing liquid,
such as a flower vase on or near the device. Never spill any liquid on the device or the power supply.
Never place any naked flame sources, such as lighted candles on or near the device. The product shall not
be used in damp or wet locations, next to a bathtub, sink, swimming pool or any other similar conditions.
Tubes produce heat. Proper ventilation has to be guaranteed all the time. The unit must not be
stacked.
Connections
Make all connections, except the connection to the headphone, whilst the unit is disconnected from
the power supply. Take care to connect the left and right channels correctly. The right channel is usually
marked red, the left channel black or white.
Please turn the volume level to minimum before connecting the headphone.
Connection to the amplifier
Connect the TAPE / RECORD OUT RCA or XLR sockets from your amplifier to the Input RCA or XLR sockets
of the headphone amplifier.
Alternatively analog sources like CD player or tuner can be reconnected to the Input RCA or XLR sockets
directly.
The Output RCA/XLR sockets of the headphone amplifier act as Loop-Out of the inputs and can be connected
to the input sockets of other audio equipment or a recorder.
Mains power connection
Connect the low voltage plug from the power supply to the Power 20V DC socket before connecting the
power supply to the mains.
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© Pro-Ject Audio Systems · Pro-Ject Head Box RS · Revision 2014.6.17
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Power switch
The rocker switch on the left side will turn the unit on or off. The blue LED above the switch shows that the unit is
switched on.
Connecting a headphone, volume control
Connect the headphones to the ¼“ (6,3mm ) jack socket on the front of the headphone amplifier. Use the
control knob to adjust the level to the required volume.
Output impedance selector
Output impedance of the amplifier can be chosen with OUT switch (5, 20, 50 ohms).
Input selector
Switch on the right side of the amplifier selects active input socket on the rear panel, XLR or RCA.

© Pro-Ject Audio Systems · Pro-Ject Head Box RS · Revision 2014.6.17
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Technical specifications Pro-Ject Head Box RS
Power output: 330mW/30ohms, 60mW/300ohms
Headphone connection: >30ohms
Signal to noise: 112dB (A weighted) at full output
Frequency response: 30Hz –20kHz /-0,05dB (10Hz –120kHz /-1dB)
THD (IMD): 0,003% (0,002%)
Gain: 11dB
Headphone jack: 3-pole ¼“ (6,3mm ) co-axial jack
Line-level input: 1 pair RCA/phono sockets & 1 pair XLR sockets
Line-level output: 1 pair RCA/phono sockets & 1 pair XLR sockets
Outboard power supply: 20V/3A DC, suitable for your country's mains supply
Power consumption: 100mA DC, <1W in standby
Dimensions W x H x D (D with sockets): 206 x 72 x 200 (209)mm
Weight: 2150g without power supply
Potential incorrect use and fault conditions
No signal on one or both channels:
No connection between headphone and headphone amplifier or amplifier. This could be due
to a faulty plug, broken wire or solder joint or simply loose plug/socket connection.
Service
Should you encounter a problem which you are not able to alleviate or identify, please contact your dealer for
further advice. Only if the problem cannot be resolved there, the unit should be sent to the responsible
distributor in your country.
Warranty
The manufacturer accepts no responsibility for damage caused by not adhering to these instructions
for use. Modification or changes to any part of the product by unauthorized persons release the
manufacturer from any liability over and above the lawful rights of the customer.
Copyright
Pro-Ject Audio Systems is a Registered Trademark of
H. Lichtenegger.
This guide was produced by Pro-ject Audio Systems
Copyright ©2014. All rights reserved.
The information was correct at the time of going to
press. The manufacturer reserves the right to make
changes to the technical specification without prior
notice as deemed necessary to uphold the ongoing
process of technical development.