Sonifex Redbox RB-BL4 review: specs & price

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Dual 2-Channel, Bi-Directional Level Converter

The Sonifex Redbox RB-BL4 is a Dual 2-Channel, Bi-Directional Level Converter with a Unbalanced level adjustable by trimmer from -28 dBu to +15 dBu, Blanaced...

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Name Sonifex Redbox RB-UL4Sonifex Redbox RB-UL2Sonifex Redbox RB-BL4Mutec Smart Clock HD MC-3.2SPL Hermes All BlackSSL XLogic X-RackLindy optical 2 Port Audio SwitchLindy optical 4 Port Audio SwitchSonifex Redbox RB-UL1Radial Engineering PhazerEarthworks Audio KP1 KickPadART AV DirectSonifex Redbox RB-DDA6ATube Amp Manufactur Amp-Switch 4/2 V2Genelec 9301ASSL MynxSonifex Redbox RB-DA6GLindy Audio Converter SPDIF DigitalTascam LA40 MK3Sonifex HY-03S Telefonhybrid
Description Quad 2-channel balancerDual 2 channel balancerDual 2-Channel, Bi-Directional Level ConverterDigital Audio & SD / HD Video Sync Master Clock GeneratorEmpty housing2 channel balancerClass A phase controllerKick PadAudio / Video Direct Box6x AES / EBU distribution amplifierAES / EBU Multi-Channel InterfaceMini X-Rack empty housingAudio InterfaceAudio Converter SPDIF DigitalLine ConverterAnalog Telephone Hybrid
Weight1.3 kg1.05 kg1.3 kg-----1 kg1.4 kg----2 kg----2.1 kg
Clock Generator
Format converter
Unbalanced- To- Balanced Converter
Telephone Hybrid
MiscellaneousPatchbayEmpty Rack, Or HousingDigital SwitchDigital SwitchPhase AdjustmentEQLevel converterDistribution AmpliferPatchbayDigitalexpanderEmpty Rack, Or HousingDistribution AmpliferDigital Switch
Frequency range-20 - 20,000 Hz---------20 Hz - 20 kHz--------
Inputs-----------2x RCA, 3.5 "mini jack and 6.3 mm jack-----1x TosLink (Optical), 1x Digital Coaxial (RCA), switchable--
Format--------------19"/ 1 U---19 "/ 1U19 "/ 1U


The Sonifex Redbox RB-BL4 is a Dual 2-Channel, Bi-Directional Level Converter with a Unbalanced level adjustable by trimmer from -28 dBu to +15 dBu, Blanaced level adjustable from -15 dBu to +15 dBu, 4 x XLR inputs, 4 x RCA inputs, 4 x XLR outputs, 4 x RCA outputs & Dimensions 48 cm (W) x 10.8 cm (D) x 4.2 cm (H). The retail price is 423.24 £.


Weight1.3 kg
Clock GeneratorNo
Format converterNo
Unbalanced- To- Balanced ConverterYes
Telephone HybridNo

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