BRIDGE 4A+

BRIDGE 4A+

19" DI box / line isolation box, 4 channels, active

Item no.: PBRIDGE4APLUS

Guarantee: 60 months

EAN: 4049521911729

Sliding scale: 1

Unit: Piece

Packaging unit: 12

Series:BRIDGE

Item highlights:

  • For connecting devices with unbalanced or balanced outputs to PA systems
  • Reliably eliminates ground loop hum thanks to galvanic transformer isolation
  • Combo inputs, can be used with XLR connectors or 1/4" jacks
  • 2 balanced XLR outputs per channel
  • Audio over Cat output (AES72 Type 5e) for forwarding all signals via a single Cat cable
  • Ground-lift switch for each output
  • Solid 19" housing, 1U
  • Power supply: 9-18V DC, center negative
  • Engineered in Germany

Specifications

Product type
DI boxes, Line isolators
Type
active
Transformer isolated
yes
Channels
4
Inputs
4
input type
balanced/ unbalanced
Input connectors
6.3 mm jack, XLR
Number of outputs
4 (+ 4 parallel XLR outs + AoC)
THRU outputs/channel
0
Output type
balanced
Output connectors
XLR, RJ45
Output attenuation (PAD)
0 dB / 20 dB
Cabinet material
sheet steel
Width
482 mm
Width
19 Inch
Depth
90 mm
Height
44 mm
Height
1 U
Weight
2.1 kg
Ground lift switch
yes
Operating voltage
9 V - 18 V
Power consumption
2 W
Additional Features
power LED, AoC output with ground lift, 6/12/18 dB gain
Ambient temperature during operation
-20 °C - 70 °C
Relative Humidity
< 80 %, not condensing
Accessories (included)
external power supply PW9V
Max. input level (< 1% THD, 20 Hz)
+10 dBu
Max. input level (< 1% THD, 1 kHz)
+16 dBu
Max. output level (<1% THD, 20 Hz - 20kHz)
+7 dBu
Frequency response (±0,2 dB, relative 1 kHz)
20 Hz - 20 kHz
Input impedance (1 kHz)
20 KOHM
Output impedance (1 kHz)
84 Ω
THD + N (30 Hz, +4 dBu, unity, unweighted)
< 0.0023%
THD + N (1 kHz, +4 dBu, unity, unweighted)
< 0.0009%
IMD (SMPTE) (60 Hz / 7 kHz, 4:1, +4 dBu)
< 0.0018%
SNR (+4 dBu, 22 kHz BW, unity, unweighted)
105 dB
Transformer ratio
10 : 1

Description

BRIDGE 4A+

The BRIDGE 4A+ is a multifunctional device: each of the four channels can be used independently as an active DI box, a line isolation box, or a booster. The input combo socket accepts unbalanced and balanced signals. The outputs are designed as two transformer-balanced XLR sockets per channel (one on the front and one on the rear).

The galvanic isolation via transformer eliminates hum loops, and the ground lift switch can also be used to eliminate noise and interference that occurs with already balanced input signals. The Palmer BRIDGE 4A+ reliably eliminates any hum - and when connecting unbalanced equipment, the signal is also balanced.

If necessary, the signal level can be raised in three stages by 6dB, 12dB or 18dB. The audio over Cat output allows the signals of all 4 channels to be routed via a single Cat cable. This saves material, space, and time.

The BRIDGE 4A+ line isolation box is a universal problem solver for eliminating ground loops. Whether it's at home, at lectures, in the rehearsal room, on stage, in clubs, or at large events - the Palmer BRIDGE 4A+ ensures a clean sound without interference anywhere.

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