Sonifex RB-HD1 Stereo Headphone Amplifier

Sonifex RB-HD1 Stereo Headphone Amplifier

The Sonifex Redbox RB-HD1 is a 1U rack-mount stereo headphone amplifier for driving up to two pairs of professional stereo headphones from a single stereo or mono input.

One headphone socket is on the front panel with one on the rear.

The main stereo input is from electronically balanced XLR-3 connectors on the rear panel, which can be wired un-balanced. The output volume for the headphones can be controlled either by a pot situated on the front panel or a VCA signal supplied externally via the remote connector. This option is controlled by the Local/Remotes Control on the rear panel.

A mono input can be mixed into the main headphone feed, for example, for mixing in talkback to the headphones. This has an input level control via a recessed adjustable potentiometer. The mono mix input can also be controlled remotely.

The stereo/mono switch is recessed on the rear panel to prevent accidental knocking.

An LED power indicator on the front panel displays the power supply connection.

• LED power indicator
• Can drive two pairs of headphones
• Rack mountable

Audio Specification

• Maximum Input Level +28dBu
• Input Impedance >20kohm balanced bridging (main), 10kohm unbal override
• Output Level Drives 150mW into 32-600ohm headphones
• Volume Control -60dB to +18dB gain
• Mono Mix Input Gain Range 22dBu

Connections

• Main Stereo Inputs 2 x XLR 3 pin female (balanced, can be unbalanced)
• Mono Mix Input 1 x XLR 3 pin female (balanced, can be unbalanced)
• Outputs 2 x 0.25" (6.3mm) A/B gauge 3-pole stereo jack sockets
• Remote Control 9-pin D-type socket
• Mains Input Filtered IEC, switchable 110-120V, or 220-240V, fused, 9W max

Physical Specification

• Weight Nett: 1.35kg
• Gross: 2.0kg
• Dimensions Raw: 48cm (W) x 10.8cm (D) x 4.2cm (H) (1U)
• Boxed: 53cm (W) x 20.5cm (D) x 6cm (H)