Palmer Bridge 4A, 4-Channel 19″ Active DI Box

The Palmer Bridge 4A, is a 4-channel, active DI box in 19″ rack format for feeding the unbalanced and high-impedance signals of electric instruments such as guitar, bass, keyboard or synthesizer into the microphone inputs of a mixing console. It provides a transformer-balanced, low-impedance signal at the outputs and eliminates mains hum and interference caused by ground loops. This keeps the sound unadulterated: brilliant, low-noise and without interference.

Each channel is equipped with a 6.3 mm jack input, a THRU-Out (for forwarding the input signals to an amplifier, for example), and two transformer-balanced XLR outputs – one at the front and one at the rear.

Thanks to a switchable 30dB pre-attenuation, the BRIDGE 4A can be fed with extremely high input levels in addition to line signals, which means it can even be looped in between the amplifier output and speakers, for example. The Audio-Over-Cat output enables the signals of all 4 channels to be routed via a single Cat (Cat5e or higher) cable. This saves material, space and time. The active circuit leaves the frequency response unaffected, achieves a high dynamic range and delivers a higher output level than a passive DI box.

The BRIDGE 4A is the ideal solution for audio technicians, semi-professional and professional musicians as well as recording studios that value reliable and durable products.

Product Specifications:

Product type: DI boxes

Type: active

Transformer isolated: yes

Channels: 4

Inputs: 4

input type: unbalanced

Input connectors: 6.3 mm jack

Input pad: 0 dB / 30 dB

Number of outputs: 4 (+ 4 parallel XLR outs + AoC)

THRU outputs/channel: 1

Output type: balanced

Output connectors: RJ45, XLR

Cabinet material: sheet steel

Width: 482 mm

Width: 19 “

Depth: 90 mm

Height: 44 mm

Height: 1 U

Weight: 1,96 kg

Ground lift switch: yes

Operating voltage: 9 V

Power consumption: 2 W

Additional Features: AoC output with ground lift, power LED

Ambient temperature during operation: -20 – 70 °C

Relative Humidity: < 80 %, not condensing

Accessories (included): external power supply PW9V

Max. input level (< 1% THD, 20 Hz): + 14 dBu

Max. input level (< 1% THD, 1 kHz): + 23 dBu

Max. output level (<1% THD, 20 Hz – 20kHz): +19 dBu

Frequency response (±0,5 dB, relative 1 kHz): 20 Hz – 20 kHz

Input impedance (1 kHz): 390 kOhm

Output impedance (1 kHz): 110 Ohm(s)

THD + N (30 Hz, +4 dBu, unity, unweighted): < 0.0026%

THD + N (1 kHz, +4 dBu, unity, unweighted): < 0.0011%

IMD (SMPTE) (60 Hz / 7 kHz, 4:1, +4 dBu): < 0.0021%

SNR (+4 dBu, 22 kHz BW, unity, unweighted): 105 dB

Transformer ratio: 1:3