Precision Audio and AV Interface Products

Radio Design Labs

RU-ASX4D Stereo Audio Selector 4x1

  • Local or Remote Controlled Switching
  • Multiple Switching Control Points
  • 4 Stereo Inputs to 1 Stereo Output
  • Line-Level Audio Switching
  • Balanced or Unbalanced Inputs and Output
  • Gain Trim on Each Source
  • Controllable Using Various RDL Remote Controls
  • Open-Collector Output for Selected Input
  • Overview
  • Specifications
  • Related Products
  • Accessories
  • Downloads
  • How to Buy
  • Product Series
  • Dimensions

The RU-ASX4D is a four channel stereo audio selector with input gain adjustments and output level metering. The inputs and outputs are connected on rear-panel detachable terminal blocks.

Each of the four stereo line level inputs accepts either a balanced or an unbalanced signal. Each input is equipped with a rear panel screwdriver-adjustable input gain trimmer. Input signal levels between -15 dBV and +8 dBu may be set to the proper operating level as indicated by a stereo dual-LED VU meter. This assures ample headroom at all normal operating levels. The module is equipped with two identical dual-led VU meters, one on the front panel, the other on the rear panel. The maximum input level is +25 dBu.

The RU-ASX4D was designed for absolute silent switching of audio signals using only solid-state switching circuitry.

The output is stereo line level. Each output channel may be connected balanced or unbalanced. Each of the VU-meters, left and right, is calibrated to read +4 dBu for the corresponding balanced output.

A front-panel LOCAL/REMOTE switch enables either the front-panel buttons or the rear-panel remote control terminals provided on detachable terminal blocks. In the LOCAL mode, four keyboard style long-life pushbuttons on the front panel are used to select one input. When a button is pushed, the corresponding audio input is fed to the output and any previously selected source is shut off. Only one source may be selected at a time. If the button for a selected source is pushed again, all inputs are turned off. An LED above each pushbutton indicates the selected source. In the REMOTE mode, inputs are selected by a sequential remote control such as an RDL D-RCS4, by a momentary remote control such as an RDL D-RC4M or by an external open-collector momentary closure to ground. The RU-ASX4D may be remote controlled from a single or from multiple locations. When a source is selected, the RU-ASX4D provides a 25 mA open-collector output to control other equipment or modules.

Rear-panel DIP switches are provided to permanently activate the remote control terminals, to select the remote control mode (sequential or individual source selection), and upon power-up a return to either a pre-programmed source or to the last source used. The pre-programmed source is stored when the module is installed.

The RU-ASX4D offers exceptional headroom, very low distortion, excellent crosstalk isolation, wide flat frequency response and extremely low noise with very high common-mode signal rejection. It provides exceptional audio performance for the most critical applications in a professional audio environment.

The RU-ASX4D operates from 24 Vdc connected through a rear-panel detachable terminal block.

Applications

Audio Inputs (4):
Stereo, Line level on Detachable Terminal Block
Input Impedance:
> 20 kΩ balanced, >10 kΩ unbalanced
Input Level (for +4 dBu output):
-15 dBV to +8 dBu, adjustable on rear-panel trimmers
Maximum Input Level:
+25 dBu
Common Mode Rejection:
> 60 dB (50 Hz to 120 Hz)
Headroom (above +4 dBu):
> 20 dB (unity gain)
Frequency Response:
10 Hz to 20 kHz (±0.2 dB)
Distortion (THD + N):
< 0.01% (20 Hz to 20 kHz)
Noise (below +4 dBu):
< -85 dB (with any input selected); < -95 dB (with no input selected)
Off Attenuation:
> 85 dB (1 kHz), > 70 dB (20 kHz)
Crosstalk:
< -85 dB (1 kHz); < -65 dB (20 kHz)
Front-Panel Switches:
Momentary pushbuttons (4, 1 per input), LOCAL/REMOTE latching pushbutton
Front-Panel Indicators (11):
Power, Selected channel (4), LOCAL/REMOTE selector (2), L and R Dual-LED VU meters (4)
Audio Output:
Stereo, Line level on Detachable Terminal Block
Output Impedance:
150 Ω balanced, 75 Ω unbalanced
Output Level:
+4 dBu balanced, unbalanced output 6 dB below balanced output level
Control inputs (5):
1 mA, pulled to ground (4, source selection); 1 mA, pulled to +15 Vdc (SEL)
Control outputs (5):
25 mA, open-collector to ground
Rear-Panel Indicators (4):
L and R Dual-LED VU meters
RDL Remote Control Compatibility:
D-RC4M, D-RCS4
Power Connection:
Detachable Terminal Block
Power Requirement:
24 Vdc @ 150 mA, Ground-referenced
Ambient Operating Environment:
0° C to 55° C
WEEE Weight:
1.26 lbs
Shipping Weight:
1.515 lbs
Tariff Code:
8543.70.9860

Documents:
Format
PDF
CAD Files:
Format
High Res Images:
Format
Declaration of Conformity:
Format

Direct Dealer Program


Becoming an RDL direct dealer is quick and easy. To become a direct dealer, your company must meet the following requirements:

  • Must be an A/V contractor, sound contractor or system integrator

  • Must possess a current resale certificate for your state

Click here to submit a new direct dealer account inquiry.


Buy Online

RACK-UP SERIES

RACK-UPs are the original 1/3 rack width 1RU rack-mountable modules for the A/V, recording and broadcast industries. Module functions include mixing, switching, pre-amplification, power amplification, distribution, gain control, equalization and more. Some RACK-UP modules are constructed in solid encapsulated durable industrial black plastic enclosures; MAX RACK-UPs are assembled using heavy duty extruded aluminum and steel panels. The rear panels feature clear bold white lettering for the terminal blocks and connectors. Reverse-printed front-panel polycarbonate laminates provide an attractive, durable finished appearance for rack-mounted or free-standing use.

Since RDL first originated 1/3 rack width modules, RACK-UPs have led the industry in economical, high-performance and cost-effective long life solutions in system designs. Multiple RACK-UP modules may be interconnected, or may be connected with other RDL modules to form all or part of an A/V system. Certain RACK-UP modules are often used free standing; all RACK-UPs may be rack mounted. A complete range of mounting options is available for systems comprised of multiple modules.

RACK-UP modules provide input, output and control connections through terminal blocks and connector (or both) according to common usage in professional installations. Front panels are equipped with connectors, user controls and LED metering, as appropriate.

Functions and features provided by RACK-UPs, since their introduction, are still available today. This continuity in product offering and support makes RACK-UP modules a preferred long-term resource for system design solutions. RACK-UP SERIES modules are designed and manufactured in the U.S.A.

RU-ASX4D RU-ASX4D