The LBB 4402/00 audio expander is an audio extension device for conference and public address systems. It features redundant network wiring, audio line input/output, adjustable audio input/output levels, etc.
The LBB 4402/00 audio expander distributes audio signals for conference and public‑address systems. It supports configurable microphone inputs, original‑language and interpretation channels, and offers flexible routing with adjustable input sensitivity and output level. Configuration is performed via a 2‑line LCD display and a rotary button, and status can be monitored with a VU meter or headphones.
The unit is housed in a 19‑inch (2U) chassis suitable for desktop or rack mounting, with dimensions of 92 × 440 × 400 mm (desktop) or 88 × 483 × 400 mm (rack) and a weight of about 7 kg. Power is supplied over Ethernet (24‑48 V DC), and the device provides multiple XLR and 3.5 mm audio I/O connectors, as well as control inputs and outputs for channel management. This manual is written in Chinese.
| Power supply voltage | 24‑48 V DC |
|---|---|
| Power consumption | 7.6 W |
| Frequency response | 30 Hz‑20 kHz (-3 dB) |
| THD (rated level) | < 0.59 % |
| Crosstalk attenuation | > 85 dB @ 1 kHz |
| Dynamic range | > 90 dB |
| Signal‑to‑noise ratio | > 87 dBA |
| XLR input nominal level | 0 dBV (+6 dB) |
| XLR input maximum level | +12 dBV |
| 3.5 mm jack input nominal level | +1.2 dBV (+6 dB) |
| 3.5 mm jack input maximum level | 0 dBV |
| Microphone input nominal level | 57 dBV (+6 dB) |
| Microphone input maximum level | 26 dBV |
| Dimensions (desktop) | 92 × 440 × 400 mm |
| Weight | 7 kg (15.4 lb) |
It receives power over Ethernet with a voltage range of 24 to 48 V DC.
Audio can be monitored via the LCD display, VU meter readings, or by connecting a headset to the headphone jack.