Palmer BRIDGE 4A+ - 19" DI box / line isolation box, 4 channels, active
BRIDGE 4A+ is a multifunctional unit: 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).
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. Palmer BRIDGE 4A+ reliably eliminates any hum – and when connecting unbalanced equipment, the signal is also balanced.
If necessary, the signal level can be increased in three steps by 6 dB, 12 dB, or 18 dB. Audio over Cat output makes it possible to route the signals from all 4 channels 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 at home, at lectures, in the rehearsal room, on stage, in clubs, or at large events – Palmer BRIDGE 4A+ ensures clean sound without interference everywhere.
- 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
General data
| Product type | DI boxes |
| Product type | Line isolators |
| Type | active |
| Transformer isolated | yes |
| Channels | 4 |
| Inputs | 4 |
| input type | balanced/ unbalanced |
| Input connectors | 6.3 mm jack |
| Input connectors | XLR |
| Number of outputs | 4 (+ 4 parallel XLR outs + AoC) |
| THRU outputs/channel | 0 |
| Output type | balanced |
| Output connectors | RJ45 |
| Output connectors | XLR |
| Output attenuation (PAD) | 0 dB / 20 dB |
| Cabinet material | sheet steel |
| Width | 482 mm |
| Width | 19 " |
| 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 | 6/12/18 dB gain |
| Additional Features | AoC output with ground lift |
| Additional Features | power LED |
| Ambient temperature during operation | -20 - 70 °C |
| Relative Humidity | < 80% (non-condensing) |
| Accessories (included) | external power supply PW9V |
Audio
| 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 Ohm(s) |
| 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 |
If you have questions about this product before placing an order, please contact our staff – we get back to you as quickly as possible, and always within 24 hours on weekdays.
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