PoE Plenum-rated Network Audio Amplifiers

Simplify Audio Installations – Deliver Network Audio and Power to Amplifiers over a Single Cable The RDL SF-NP16E and SF-NP35E Network Amplifiers convert a single Dante or AES67 audio channel to a 70 V or 100 V constant voltage amplified output. Amplifier features: PoE powered Plenum Rated per UL Standard 2043 Integral VCA for optional user […]

Automatically Adjust Audio Level when HVAC System Turns On

Noisy HVAC System?  Using just a couple of RDL modules, the level of your audio system can automatically adjust to compensate for the increased noise level when the HVAC system turns on.  This is useful for background music systems, paging systems or any type of public address or mass notification system. A contact closure provided […]

Muting a Sound System During a Fire Alarm

In public buildings it is often required that sound systems be muted during a fire alarm. The installer of the fire alarm system will generally provide the installer of the sound system with a set of dry relay contacts to initiate a sequence of control that is, hopefully, well defined in the project specifications and […]

FORMAT-A Signal Breakout

The RDL TX-TP4PW Format-A Power Inserter / Signal Breakout is used in a variety of applications where it is necessary or more practical to provide each FORMAT-A sender and / or receiver with its own cable run rather than looping products together in the field. For installations where senders are located in separate rooms, the […]

Adapt Existing Audio Power Amplifiers to a Dante Network

Upgrading a sound system to include Dante networked audio doesn’t mean replacing all of the existing power amplifiers. An FP-NML2 Network to Mic/Line Interface will convert 2 Dante audio channels for connection to any device with analog mic or line-level inputs. Each output is equipped with a recessed “MIC/LINE” switch that allows the installer to […]

Choose the Audio Relay with the Correct Release Time

The ST-VOX1 Voice Operated Relay can be actuated by an unbalanced mic or line level source. It is primarily used in intercom and talkback applications where a fast contact release time (adjustable 70 to 260 ms) is desired. In applications where longer release times are desired we suggest the use of ST-ACR Series Audio Controlled […]

Compact Near Field Monitor Speaker for Conference Facilities, Courtrooms and Legislative Chambers

The D SERIES-SP1A Decora-Style Loudspeaker is ideal for use as a near field monitor in courtrooms, legislative chambers and conference facilities. Designed for mounting in a single gang of a North American electrical switchbox or RDL Desktop Chassis, this compact package offers surprising frequency range, clarity and durability. A companion amplifier for the –SP1A is […]

Remote Switching of Speaker-Level Signals

In installations that require the capability to remotely switch loudspeakers off or on when portions of a facility are not in use, the RDL ST-LCR1H High Power Logic Controlled Relay and D Series-RT2 Remote Control Selector provide the ideal solution. The ST-LCR1H is capable of switching speaker loads up to 500 Watts. The D Series-RT2 […]

Conserve Rack Space by Using RDL’s DIN Rail Mounting Brackets

35 mm DIN rail is widely used in commercial and industrial communications and control systems for mounting terminal strips, power supplies, relays and controllers in equipment racks and enclosures or on communications back-boards.  DIN rail provides integrators with a common method of mounting system components from a variety of sources in a wide range of […]

Passive Audio Combining and Dividing

The RDL STD Series of Divider / Combiners provide a cost effective way of combining audio signals from multiple sources with similar impedance and level characteristics or for distributing a single audio signal to multiple inputs. They are frequently used to combine stereo sources to mono or to combine several microphones to a single output. […]

Add Additional Audio Inputs to an Existing Mixer

The ST-MX3 is a quality, yet cost effective way of mixing up to three line-level signals to a single line-level output. Balanced and/or unbalanced line-level signals of different levels and impedances may be combined with typical RDL low-noise and low-distortion performance.   The ST-MX3 is often used for: adding additional inputs to an existing mixer […]

Vinyl or Bust!

The RDL ST-PH1 Stereo Phono Preamplifier provides DJ’s and audiophiles a high quality method of interfacing the cherished turntable with newer professional or consumer audio systems that might not have PHONO inputs.     The ST-PH1 features: Industry standard 47 kΩ unbalanced inputs Outputs drive high or low impedance / balanced or unbalanced lines Equalization […]

Monitor up to 12 Channels of Audio in a Single Rack Unit

Used in commercial, professional, studio and broadcast applications to measure and display audio levels, the RU-SM16A and RU-SM16D provide a flexible, precision analog audio metering solution. InfoComm Product Overview Video Rear-panel switches allow the user to define each meter string in terms of: LEVEL: Line-level – Balanced or Unbalanced 25V Constant Voltage or 8W < […]

Isolated Mixing of Two Unbalanced Line-Level Audio Sources

The RDL TX-MX2R is often used in commercial and residential sound systems to provide active, isolated mixing of a single unbalanced line-level stereo source to dual mono outputs. It can also be used to mix two separate mono sources. Featuring high-impedance inputs that are mixed using an active summing amplifier, the TX-MX2R can be used […]

Compact Mono and Stereo Audio Format Conversion

The RDL TX-A2 Balanced to Unbalanced Audio Converter is a passive device providing isolation and attenuation between a balanced +4 dBu mono source and two unbalanced -10 dBv mono inputs. Isolation is provided by a studio-quality transformer with its output coupled to a resistive attenuation network. The TX-A2D Balanced to Unbalanced Dual Audio Converter provides […]

STICK-ON Mic Preamps – Which One do I need?

RDL STM-1, STM-2 and STM-3 Microphone Preamplifiers all seem to look alike and indeed they do have some similarities: GENERAL Identical noise, distortion, frequency response, headroom and common mode rejection specifications. Identical power requirements. 24 vdc @ 25 mA or 12 vdc with a 6 dB reduction in headroom. INPUT Balanced or unbalanced Balanced input accepts […]

Automatic Audio Ducking

In audio, a Ducker is a device used for lowering the level of one audio source based on the presence of another audio source. Often used in paging systems to lower the level of background music during a page, duckers are also used for voiceovers in radio, television and film production. The RDL ST-VP2 Automatic […]

STICK-ON® Compressor/Limiter

When line-level inputs need to be protected against level increases or overloads that cause clipping and distortion, the RDL ST-CL2 Compressor/Limiter is the ideal solution. The ST-CL2 is designed to maintain a constant average output level and provide effective peak control over a wide range of input levels. It can be used to prevent overloading […]

Tidy Up Your Projector / Amplifier Installations

The RDL PM-3T Pole Mount tray provides the perfect solution for the tidy, professional installation of any RU, TX, FP or STICK-ON Power Amplifier and Power Supply that is used in conjunction with a projector.  The design of the PM-3T allows it to be quickly installed above the projector even after the projector is in […]

Compact STICK-ON Audio Distribution

Ever have the need to split an audio signal to 3 separate locations?  How about balance a line-level audio signal and then distribute it?  Maybe your installation requires audio distribution with gain or loss?  Need to distribute an audio line but have no room for a larger conventional distribution amplifier?  Then we may just have […]

High Quality Audio Amplification in the Most Extreme Heat

There are times when it is necessary to install a power amplifier in an uncontrolled environment where ambient temperatures can exceed the normal operating range of traditional electronic equipment. The RDL FP-PA18H 18 W Mono Hi-Temp Audio Amplifier is the ideal solution for these types of environments. It is designed to operate in ambient temperatures […]

Power Supplies

All active RDL modules operate on 24 VDC. Current requirements for each module differ. Using a 24 volt AC power adaptor will likely cause the module to release its MAGIC SMOKE and will certainly void the warranty. Most modules do not ship with a power supply. The reasoning behind this is that in many cases […]

RLC10K Remote Level Control

If you’ve ever used RDL’s ST-VCA3, RU-VCA2 or RU-VCA2D voltage controlled amplifiers, you are without a doubt familiar with the RLC10K remote level control. This premium quality, all-metal remote control is well known for its ease of installation and professional, aesthetic appearance. What might not be so well known is how easily the RCL10K can […]

Low Input Signal?

Do you love the RDL TX-J2 but sometimes run into situations where your input signal is a little low and could use a bit of gain?  Take a look at our TX-LC2 and prepare to fall in love again!  Like the TX-J2, the TX-LC2 mixes two unbalanced line-level signals into a mono balanced output but […]

Rack Mounting Decora® Remote Controls and Panels

Decora® style remote controls and wall panels are typically mounted in a wall, but given the compact design and wide variety of products available in RDL’s D-Series product offering, RDL customers may wish to mount these products in a rack.  RDL remote controls and D-series panels can be readily rack mounted using the RM-D3 or […]


ANALOG TO DIGITAL / DIGITAL TO ANALOG CONVERSION Broadcasters, mastering studios and system integrators rely on RDL to provide Analog to Digital and Digital to Analog converters with low distortion, low noise and flat frequency response. The HR-ADC1 provides conversion of balanced or unbalanced line-level analog audio to AES/EBU, AES-3ID or Coaxial S/PDIF digital audio […]


In a perfect world, the audio connections between different pieces of gear would all be alike.  Unfortunately, this is not the case and likely never will be. Balanced and unbalanced audio lines (1) are not inherently compatible and unless they have some help they don’t always play well together. For passive conversion from balanced to […]

Audio Message Repeater for Retail Stores, Hospitals and More

Transportation centers, hospitals, retail outlets, entertainment centers and factories often require that a voice message or series of voice messages be repeated over the public address system at given intervals or upon certain conditions. The RDL FP-MR2 Message Repeater provides up to one minute and forty seconds of music quality digital message storage. Playback of […]

Power Supply Mounting

External power supplies and the associated power cords and low voltage leads can present a problem and even a safety hazard in some, especially compact, A/V installations. For installations requiring the use of multiple power supplies, RDL offers numerous solutions for mounting both wall wart and desktop type power supplies: WH1 and WH2 “Warthog” Power […]

Push-to-Talk Microphone Preamplifier

Some microphones equipped with a push-to-talk function may not mute and unmute as quietly as desired, or some installations (typically paging) may have a microphone which does not have a push-to-talk feature. The RDL STM-2X Switchable Microphone Preamplifier is the perfect solution when quiet on / off switching is required for dynamic or condenser microphones. […]

70V to Unbalanced Line-Level Conversion

Do you ever need to feed the audio from a 70V distributed loud speaker system into a line-level device in a remote location? Do you ever need a few more loudspeakers than your existing 70V amplifier can drive but have no convenient line-level audio to run into a local amplifier? Well RDL has the module for […]

Kill Ground Loop Hum with the EZ-HK1 Stereo Audio Hum Killer

Ground loop hum is often encountered whenever two pieces of unbalanced audio equipment are connected together but are being powered from outlets on different circuits. The difference in ground potential between two pieces of unbalanced audio equipment can be a major cause of noise in audio systems today. The EZ-HK1 eliminates hum due to ground loops […]


Turn on a visual indicator, mute a local sound system or switch loudspeaker loads anytime your paging system is active. The RDL TX-PCR1 Paging Controlled Relay can accomplish these chores and more. Simply connect the input of the TX-PCR1 to any 25 V, 70 V or 100 V (8 Ohm up to 75 Watts) speaker […]


When unbalanced stereo (consumer) lines need to be combined and balanced the RDL TX-J2 Unbalanced Input Transformer is a handy tool to have available. The TX-J2 provides two phono jack inputs that are passively combined and balanced through transformers configured to reject induced hum. A balanced line-level output is provided on a detachable terminal block […]


Are you stuck with a flat panel display that only has speaker level outputs? Do you need to add more speakers and amplifiers to an existing speaker circuit in a remote location? The RDL TX-8A 4 Ohm / 8 Ohm Input Interface will simplify the process of integrating these pieces of equipment with the rest […]

More Phantom Power to You

The RDL STD‑150 is a passive audio combiner/divider designed around the standard microphone output impedance of 150 Ohms. If you need to mix two or three microphones at the same level or if you need to split a mic signal to two or three locations, the STD‑150 is a practical yet elegant approach. If the […]