Sound Devices HX-3 User Manual

HX-3

Headphone Distribution Amplifi er
User Guide and Technical Information

Sound Devices, LLC

300 Wengel Drive • Reedsburg, WI • USA
[phone] • fax: [phone]
Toll-Free: [phone]
www.sounddevices.com
[e-mail]

HX-3 User Guide and Technical Information

General Description

The HX-3 from Sound Devices is a portable, stereo headphone amplifi er designed for critical audio
monitoring. The audiophile-quality headphone amp is ideal for adding headphone feeds for portable
and studio applications.

The HX-3 provides three independent headphone feeds from balanced or unbalanced, line sources. Each
headphone output has its own level control, peak LED, and ¼-inch output connector. With its extended
bandwidth and high drive capability the HX-3 can drive headphones of various impedances to high
levels with very low distortion, important for monitoring in high SPL environments. It is powered from
two-AA batteries or external DC.

The HX-3 will provide years of superb audio performance under the most punishing fi eld conditions.

Features

High Performance Headphone Amplifi er

• Three independent headphone outputs with individual volume controls.

• Dynamic range exceeding 120dB.

• 10 Hz to 50 kHz audio bandwidth.

• Capable of driving headphones to high levels with very low distortion.

• Peak indicators show overload of each headphone feed.

• Stereo / Mono switch.

Flexible Inputs / Outputs

• Two balanced XLR line level inputs or unbalanced ¼-inch and 1/8-inch stereo inputs.

• Loop output to connect additional HX-3’s in series for extra headphone outputs.

Flexible Powering

• Internal battery power (two AA) for convenient, low cost power.

• Excellent battery life - greater than 10 hours (nominal drive level with alkaline batteries).

• External 5-17 VDC powering.

Durable Mechanical Construction

• High strength aluminum chassis withstands punishing fi eld conditions.

• Strap loops on each side for easy mounting or wearing.

• Panel-mounted connectors for strength and reliability.

• Easy access battery compartment for quick battery changes.

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Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.

Specifi cations

HX-3 User Guide and Technical Information

Frequency Response:

Voltage Gain:

Output Clipping Level:

Headphone Output Impedance:

Input Clipping Level:

Dynamic Range:
(Balanced line inputs)

THD + Noise:

Inputs:

Loop Output:

Internal Voltage Rails:

10 Hz – 50 kHz, +/-1.0 dB, any input to any output, gain control set to 50%

Gain Loop Out Headphone Output (1,2,3)

Bal. Line –3 dB 34 dB

HP Input –1 dB 35 dB

+18 dBu minimum with 600 ohm load
+16 dBu minimum with 300 ohm load

200 ohms

XLR: +24 dBu minimum

120 dB minimum

0.03% maximum (from 10 Hz – 22 kHz @ +10 dBu input and output level, 300 ohm load, 10 Hz – 22
kHz filter bandwidth)

XLR: electronically balanced, 22k ohm input impedance

1/4-inch unbalanced: 9.1k ohm impedance

1/8-inch unbalanced: 9.1k ohm impedance

Note: only one set of inputs (balanced or unbalanced) should be connected at a time.

Unbalanced, 200 ohm output impedance

±15 V and –15V, regulated

Power:

Power LED:

Operating Temperature Range:

Dimensions:

Weight: (unit only)

Included Accessories:

Internal: 2 AA alkaline batteries, 12 hours life typical driving one 75 ohm headset.

External: 5–17 VDC via threaded coaxial connector, (5.5 mm outer diameter, 2.1 mm inner diameter),

pin positive, sleeve negative. Voltages above 17 VDC cause no damage to unit, but will open an inter­nal poly fuse. Poly fuse will reset when voltage is removed.

Green indicates power and good battery. Red indicates power with low batteries. LED turns red when
approximately 4 hours of battery life remain.

0 to 70° C

32 to 160° F

43 mm x 94 mm x 140 mm (h x w x d)
(1.7” x 3.7” x 5.55”)

0.56 kg, 1.24 lbs.

1/4-inch to 1/8-inch
Tip-Ring-Sleeve interconnect cable
rubber feet (4)

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