The HX-3 Portable Headphone Amplifier from Sound Devices can produce very high headphone levels with extremely low noise and distortion. The compact HX-3 headphone distribution amplifier is the perfect accessory to quickly provide three high-performance stereo headphone feeds with individual level controls from line-level sources.
The HX-3 accepts balanced XLR line-level inputs or unbalanced ¼-inch and 1/8-inch stereo inputs. Its ¼-inch loop-out can connect multiple HX-3's for additional headphone outputs. Headphones are connected to panel-mounted ¼-inch stereo connectors.
The HX-3 has a durable aluminum chassis to withstand the punishment of field and studio environments. The unit is powered by inexpensive batteries (two-AA) or external 5-18 VDC.
Sound Devices HX-3 Features
- Three isolated headphone outputs with individual volume controls
- 125 dB dynamic range with flat frequency response
- Durable ¼-inch connectors, panel mounted for strength
- Stereo or mono monitoring
- Peak LED indicates headphone overload
- 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
- All-metal connectors solidly mounted to the chassis for durability and RF immunity
- Free from "Pin-1" grounding problems
- Internal battery-power for up to 18 hours from two AA alkaline batteries
- Chassis-isolated 5 to 18 VDC input for easy external DC powering
- Power LED indicates low battery power
- High strength, extruded aluminum chassis with protective metal end panels
- HX-3 portable headphone amplifier1
- 1/4" to 1/8" TRS interconnect cable1
- Rubber feet4
- Locking DC jack1
- Frequency Response10 Hz – 50 kHz, -±1.0 dB, any input to any output, gain controls set to 50%
- Voltage Gain34 dB from balanced line to headphone output, 35 dB from headphone input to headphone output
- Output Clipping Level+18 dBu minimum with 600 ohm load, +16 dBu minimum with 300 ohm load
- Headphone Output Impedance200 Ω
- Input Clipping Level
- XLR: +24 dBu minimum
- 1/4" and 1/8" Inputs: +22 dBu minimum
- Dynamic Range (balanced line inputs)0.03% maximum (from 10 Hz to 22 kHz @ +10 dBu input and output level, 300 ohm load, 10 Hz – 22 kHz filter bandwidth)
- Inputs
- XLR: electronically balanced, 22kΩ input impedance
- 1/4" unbalanced: 9.1kΩ impedance
- 1/8" unbalanced: 9.1kΩ impedance
- Internal Voltage Rails±15 V, regulated
- Power Source
- Internal: 2 AA batteries (18 hours typical life with nominal levels)
- External: 5 – 17 VDC via threaded coaxial connector (5.5 mm outer diameter, 2.1 mm inner diameter), pin positive, sleeve negative
- Power LED
- Green: indicates power and good battery
- Red: indicates power with low batteries (LED turns red when 4 hours of battery life remain)
- Operating Temperature32°F to 160°F (0°C to 70°C)
- Dimensions (HxWxD)1.7" x 3.7" x 5.5"
- Unit Weight1.24 pounds
