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BASIC CLASSROOM WITH PROJECTOR Computer, Projector w/ variable output, 40 Watt Stereo Audio Amplifier
BASIC CLASSROOM WITH PROJECTOR
Computer, Projector w/ variable output, 40 Watt Stereo Audio Amplifier
AN-2049
Description:
This classroom is equipped with a computer, projector and overhead speakers. The computer is connected to a jack plate at the front of the room. Audio and video from the audio/video input plate is connected to the projector using standard audio wiring and monitor cable. The projector is used to control the audio level to the speakers. The projector must be equipped with a variable level audio output. Each output channel of the power amplifier powers one 8 Ω speaker. All wall controls and panels are offered in RDL standard white/gray or in stainless steel with custom labeling available.

USE A CATX HOME RUN FOR EACH FORMAT-A SOURCE Power Inserter / Signal Breakout Module Permits Home Run Cabling to Dante™ Network
USE A CATX HOME RUN FOR EACH FORMAT-A SOURCE
Power Inserter / Signal Breakout Module Permits Home Run Cabling to Dante™ Network
AN-2233
Description:
In this Format‑A installation, it was not practical to loop CATx cable between the senders in different rooms. A home run from each microphone sender was pulled to the equipment rack. The TX‑TP4PW Power Inserter / Signal Breakout module is used to connect Pairs A, B and C to a single cable run and to insert power. The sources sent on pairs A, B and C are all present on the cable that connects the TX‑TP4PW to the RJ45 input of the RU‑FN format‑A to Network Interface. Each of the three sources will be transmitted on a separate Dante channel. All the Format‑A modules are powered by the external supply connected to the TX‑TP4PW.

COMPACT CLASSROOM SOUND SYSTEM Integrated Mixer/Amplifier for Classroom
COMPACT CLASSROOM SOUND SYSTEM
Integrated Mixer/Amplifier for Classroom
AN-2111
Description:
Audio sources in this classroom connect directly to inputs of the RDL EZ‑MXA20 20 Watt Stereo Mixer/Amplifier. Audio from a laptop and from a wireless mic receiver feed the two stereo line level inputs. This still leaves a phantom‑powered mic input available for occasional use of a lectern or for future expansion. The EZ‑MXA20 provides 10 Watts per channel to the classroom 8 Ohm speakers and allows bass and treble tone control. The EZ‑UCB2 Under Counter Bracket allows mounting below the desktop to conserve desk space while maintaining easy access to controls.

CLASSROOM W/ PROJECTOR AUDIO/VIDEO SWITCHING Computer, Auxiliary Input, Projector w/ variable output, 40 Watt Stereo Audio Amplifier
CLASSROOM W/ PROJECTOR AUDIO/VIDEO SWITCHING
Computer, Auxiliary Input, Projector w/ variable output, 40 Watt Stereo Audio Amplifier
AN-2048
Description:
This classroom is equipped with a computer and with jacks for an auxiliary audio/video source such as a DVD player or VCR. The computer is connected to a jack plate at the front of the room. The auxiliary input is shown at the rear. Audio and video from each of the audio/video input plates is connected to the projector using standard audio wiring and monitor cables. The projector is used to switch between sources and to control the audio level to the speakers. The projector must be equipped with a variable level audio output. Each output channel of the power amplifier powers two 8 Ω speakers. All wall controls and panels are offered in RDL standard white/gray or in stainless steel with custom labeling available.

BASIC CLASSROOM WITH INTEGRATED MIXER AMPLIFIER Microphone, Laptop Audio, DVD Player, 20 Watt Mixer Amplifier
BASIC CLASSROOM WITH INTEGRATED MIXER AMPLIFIER
Microphone, Laptop Audio, DVD Player, 20 Watt Mixer Amplifier
AN-2017
Description:
The EZ‑MXA20 provides a microphone preamp, mixer, limiter, tone control, and a stereo power amplifier in a package less than six inches wide. The EZ‑MXA20 handles sound reinforcement whether the audio source is a computer, DVD player, live presenter, or all three. The power amplifier provides 10 Watts per channel into 8 Ohm speakers or 8 Watts per channel into 4 Ohm speakers. Bass and treble tone controls provide equalization of source material. The limiter controls overloads from clipping the amplifier and an LED on the front panel of the EZ‑MXA20 indicates when the limiter is active.

4 x 1 STEREO AUDIO SWITCHING IN A CLASSROOM Remote Source Selection and Volume Control
4 x 1 STEREO AUDIO SWITCHING IN A CLASSROOM
Remote Source Selection and Volume Control
AN-2211
Description:
The classroom is equipped with three A/V sources (Computer, DVD and VCR) and an audio‑only input on a wall plate. Staff selects the audio source and sets the level through the RDL RU‑ASX4DR Remote Controlled Audio Selector using a D‑RC4M Four Channel Remote Control and a D‑RLC10M Remote Level Control. All video signals are run directly to the projector which provides video source selection. Sources may be muted by simply de‑selecting the active input at the D‑RC4M or by operating the MUTE switch on the D‑RLC10M. The D‑CIJ3D Consumer Input Jack Panel is used to balance the stereo signal of an MP3 player or any consumer source and to provide galvanic isolation.

LOCAL ZONE LEVEL CONTROL OF NETWORKED AUDIO Adapt Standard Audio Amplifiers to a Dante&trade Network
LOCAL ZONE LEVEL CONTROL OF NETWORKED AUDIO
Adapt Standard Audio Amplifiers to a Dante&trade Network
AN-2237
Description:
An FP‑NML2V Network to Mic/Line Interface with VCA receives two channels of Dante networked audio, one for each room or zone. The digital audio is converted to balanced audio to drive any standard amplifier. The FP‑NML2V incorporates a VCA in each audio output. Each VCA is controlled by a D‑RLC10 Remote Level Control in the zone. The D‑RLC10 is a rotary encoder style remote that provides a 0 to 10 Vdc control output. One FP‑PA35A Power Amplifier drives the speakers in each zone. The amplifier gain is fixed at the maximum level needed in the zone. Users adjust the audio level in the zone using the D‑RLC10. Because the level in the zone is adjusted by the FP‑NML2V, any standard audio amplifier may be used for each zone.

BASIC TWO ROOM COMBINING SYSTEM School Cafetorium Room Combining System with Automatic Audio Leveling Compression
BASIC TWO ROOM COMBINING SYSTEM
School Cafetorium Room Combining System with Automatic Audio Leveling Compression
AN-2124
Description:
This cafetorium can be used as one large room or as two smaller rooms formed by movable wall partitions. Each room has one mic and one mono or stereo line‑level input connection through a DS‑J3 input plate. EZ‑MCP1 Microphone Compressors provide consistent level and overload protection on the mic inputs. ST‑CL2 Compressor/Limiters provide the same benefits for the line inputs. The DS‑RCX2 Room Controls provide volume control in each room and allow selection of a common external source (typically background music). The RCX‑5C controls the audio system configuration, separating or combining the inputs and amplified audio to the speakers according to the room usage (one large room or two smaller rooms). The paging input overrides the audio in the entire cafetorium. Note: The RCX‑5C can be used for room combinations from two to five rooms. An HD‑PA35UA Audio Power Amplifier is used for each zone in this system to feed 70 Volt speakers. The HD‑PA35UA has an automatic sleep mode that shuts off the power amplifier when it is not in use. This offers significant energy savings for systems not operated by technical staff.

NETWORKED AUDIO - ADDING NEW CHANNELS BGM and Paging Audio Transmitted Between Buildings Over Existing Network
NETWORKED AUDIO - ADDING NEW CHANNELS
BGM and Paging Audio Transmitted Between Buildings Over Existing Network
AN-2228
Description:
Dante™ networked audio is ideal for audio systems with large channel counts and is equally beneficial in much smaller systems. Cost savings can result from utilizing Dante to transport one to four channels of audio over an existing Local Area Network which would otherwise require the installation of dedicated audio cable between buildings in a school, hospital, church, office complex or factory. This diagram shows background music and a paging microphone sent via Format‑A directly to a local Mixer‑Amplifier in the main building. The Format‑A cabling also sends these sources to the RU‑FNP Format‑A to Network Interface which converts the two sources to two Dante network channels. The signals travel through the network to the satellite building(s) where they are converted back to audio by the FP‑NML2 Network to Mic/Line Interface to feed the BGM and Paging inputs of a Mixer‑Amplifier.

GATED MIC PREAMPLIFIER DETECTS SIGNAL PRESENCE Preamp Suppresses Ambient Noise While Idle and Provides Visual Indication of Speech Activity
GATED MIC PREAMPLIFIER DETECTS SIGNAL PRESENCE
Preamp Suppresses Ambient Noise While Idle and Provides Visual Indication of Speech Activity
AN-2176
Description:
The ST‑GSP1 Gated‑Speech Preamplifier produces gated line‑level audio from a balanced dynamic or condenser microphone. The preamp output remains off when no one is speaking into the microphone, thereby not picking up and amplifying ambient room noise. The moment someone speaks into the microphone, the output of the ST‑GSP1 turns on, feeding line‑level audio to the sound system. The SLAVE output terminal is used to activate the ST‑LCR1 Logic Controlled Relay which provides a contact closure to turn on a visual indicator. The indicator lamp confirms to the person speaking that the microphone is active. Additional contacts on the ST‑LCR1 are available to turn on other indicators or recording devices. The ST‑GSP1 detection threshold is adjustable. Muting occurs 2 seconds after the audio level drops below the preset threshold. In circumstances where a longer delay time is desired, an external capacitor may be connected to extend the delay. The ST‑GSP1 line‑level output may be configured balanced or unbalanced to feed a variety of audio inputs.

CLASSROOM SYSTEM WITH SCHOOL-WIDE PAGING Full-Featured “Green” Mixer Amp Integrates Paging in the Classroom
CLASSROOM SYSTEM WITH SCHOOL-WIDE PAGING
Full-Featured “Green” Mixer Amp Integrates Paging in the Classroom
AN-2132
Description:
Classroom mic, line and computer audio sources are connected to the HD‑MA35UA Mixer Amplifier through RDL wall plates. A school‑wide paging feed connects directly to the mixer amplifier paging input. The paging source may be either mic or line level. VOX switching eliminates the need for push‑to‑talk contacts. The HD‑MA35UA setup allows flexibility in muting or ducking the other input channels during paging. The only active RDL component is the HD‑MA35UA which powers up when audio is detected. When the system is inactive (no audio in use) it enters the sleep mode, consuming less than one watt for optimum energy conservation. The HD‑MA35UA returns to active mode (turns on) automatically when an audio input becomes present.

CLASSROOM WITH WALL-MOUNTED THREE-INPUT MIXER Computer, Auxiliary Input, IR Receiver, Projector, Twisted Pair Audio Wiring, 40 Watt Audio Amplifier
CLASSROOM WITH WALL-MOUNTED THREE-INPUT MIXER
Computer, Auxiliary Input, IR Receiver, Projector, Twisted Pair Audio Wiring, 40 Watt Audio Amplifier
AN-2044
Description:
This classroom is equipped with a computer and with jacks for an auxiliary audio/video source such as a DVD player or VCR. The computer is connected to a jack plate at the front of the room. The auxiliary input is shown at the rear. Audio from the audio/video input plates is connected to two inputs of a three input audio mixer located near the projector using twisted‑pair cable. The third mixer input is fed from the line‑level output of an IR receiver. (Note: A paging source could be connected to the third mixer input instead of the IR receiver, if desired.) The video is connected directly to the projector using coaxial and monitor cables. The projector audio output is not used. The mixer controls the level of each audio source using the associated wall mounted mixer remote control. The three knobs on the wall control provide separate audio level adjustment for the computer, auxiliary input and IR receiver. Each output channel of the power amplifier powers two 8 Ω speakers. All wall controls and panels are offered in RDL standard white/gray or in stainless steel with custom labeling available.

DISTRIBUTED VGA VIDEO TO MULTIPLE MONITORS Hotel Provides Multiple Video Monitors that Display Daily Schedule of Events
DISTRIBUTED VGA VIDEO TO MULTIPLE MONITORS
Hotel Provides Multiple Video Monitors that Display Daily Schedule of Events
AN-2090
Description:
The daily Calendar of Events listing at this hotel is generated from an office computer. An RDL EZ‑VM14 distributes the VGA signal of the schedule display to three monitors located near the entrances of the hotel meeting rooms. The wide bandwidth of the EZ‑VM14 insures that the same high resolution image seen at the local monitor is seen at each hotel monitor.

MIX MIC SOURCES IN A ROOM TO ONE DANTE™ CHANNEL Expand the Capacity of a Single Dante Channel Using a Format-A Three-Pair Combiner
MIX MIC SOURCES IN A ROOM TO ONE DANTE™ CHANNEL
Expand the Capacity of a Single Dante Channel Using a Format-A Three-Pair Combiner
AN-2231
Description:
The TX‑TPSA1A Three‑Pair Combiner to Single‑Pair Sender is used to add up to two additional sources to one pair in a Format‑A system. Each of the three D‑TPS1A single‑pair microphone senders is set to feed a unique pair (A, B or C). These senders are daisy chained on one CATx cable run connected to the INPUT of the TX‑TPSA1A combiner where the three pairs are summed to feed Pair A. The TX‑TPSA1A output feeds an RDL RU‑FN Format‑A to Dante Interface. Microphones connected to any of the mic‑input senders will be sent on the first Dante output channel. Two D‑TPSL1A single‑pair senders (set to feed pairs B and C) are looped together on a second cable run connected to the LOOP IN of the combiner. These sources will be sent independently on the second and third Dante channels. DC power connected to the TX‑TPSA1A powers all five senders. Note: Up to three TX‑TPSA1A modules may be daisy chained on one cable run, permitting as many as nine senders to feed audio through a single Format‑A cable and to be sent on three Dante network channels.

ELIMINATE AUDIO AND VIDEO HUM IN CLASS ROOM Galvanic Isolation for Audio and Composite Video “Ground Loops”
ELIMINATE AUDIO AND VIDEO HUM IN CLASS ROOM
Galvanic Isolation for Audio and Composite Video “Ground Loops”
AN-2101
Description:
Picture and sound quality from the player on the equipment cart is easily degraded by a “ground loop”. The difference in ground voltage between the audio/video source and monitoring locations can create herringbone or rolling hum bars in the video, and hum in the audio. Small “ground loop” voltages can easily impair the quality of audio and/or video signals. The RDL EZ‑HK3 removes the “ground loop” using a stereo pair of high quality audio and video transformers in a shielded metal enclosure. The input jacks are ground‑isolated. A ground‑lift switch allows the output jack shields to be lifted from the metal chassis if required.

CONSUMER TO PRO AUDIO FORMAT CONVERSION Stereo Unbalanced Audio Source Connects to Stereo Balanced Mixer Input
CONSUMER TO PRO AUDIO FORMAT CONVERSION
Stereo Unbalanced Audio Source Connects to Stereo Balanced Mixer Input
AN-2190
Description:
A portable podium is frequently used for presentations in this room. An ST‑UBA2 Unbalanced to Balanced Line Amplifier is installed in the floor box to convert the unbalanced stereo audio signal from a laptop computer or other consumer source to match the balanced stereo inputs of a professional mixer. Each channel is provided with installer‑adjustable gain and a Dual‑LED VU meter to simplify adjustment. A summed mono output is also available. The small size of the ST‑UBA2 permits it to be comfortably installed in a floor box.

CLASSROOM WITH PROJECTOR AUDIO/VIDEO SWITCHING Computer, Auxiliary Input, Projector w/ variable output, Twisted Pair Audio Wiring, 40 Watt Audio Amplifier
CLASSROOM WITH PROJECTOR AUDIO/VIDEO SWITCHING
Computer, Auxiliary Input, Projector w/ variable output, Twisted Pair Audio Wiring, 40 Watt Audio Amplifier
AN-2045
Description:
This classroom is equipped with a computer and with jacks for an auxiliary audio/video source such as a DVD or VCR player. The computer is connected to a jack plate at the front of the room. The auxiliary input is shown at the rear. Audio from each of the audio/video input plates is connected to the projector using twisted‑pair cable. The video is connected using coaxial and monitor cables. Identical jack plates are mounted in the classroom wall and in a box near the projector so the room may be pre‑wired. Installation of the projector is facilitated by plugging its cables into the jacks. The projector is used to switch between sources and to control the audio level to the speakers. The projector must be equipped with a variable level audio output. Each output channel of the power amplifier powers two 8 Ω speakers. All wall controls and panels are offered in RDL standard white/gray or in stainless steel with custom labeling available.

CLASSROOM WITH WALL-MOUNTED THREE-INPUT MIXER Computer, Auxiliary Input, IR Receiver, Projector, Twisted Pair Audio Wiring, 20 Watt 70 or 100 Volt Audio Amplifier
CLASSROOM WITH WALL-MOUNTED THREE-INPUT MIXER
Computer, Auxiliary Input, IR Receiver, Projector, Twisted Pair Audio Wiring, 20 Watt 70 or 100 Volt Audio Amplifier
AN-2043
Description:
This classroom is equipped with a computer and with jacks for an auxiliary audio/video source such as a DVD player or VCR. The computer is connected to a jack plate at the front of the room. The auxiliary input is shown at the rear. Audio from the audio/video input plates is connected to two inputs of a three input audio mixer located near the projector using twisted‑pair cable. The third mixer input is fed from the line‑level output of an IR receiver. (Note: A paging source could be connected to the third mixer input instead of the IR receiver, if desired.) The video is connected directly to the projector using coaxial and monitor cables. The projector audio output is not used. The mixer controls the level of each audio source using the associated wall mounted mixer remote control. The three knobs on the wall control provide separate audio level adjustment for the computer, auxiliary input and IR receiver. The audio power amplifier provides a 70 V and 100 V constant‑voltage output to power multiple speakers. The four speakers shown may each be tapped for 5 watts. All wall controls and panels are offered in RDL standard white/gray or in stainless steel with custom labeling available.

AUDIO EQUALIZATION ENHANCES VOICE INTELLIGIBILITY AUDIO EQUALIZATION ENHANCES VOICE INTELLIGIBILITY
AUDIO EQUALIZATION ENHANCES VOICE INTELLIGIBILITY
AUDIO EQUALIZATION ENHANCES VOICE INTELLIGIBILITY
AN-2178
Description:
The ST‑EQ3 3 Band Equalizer shown in this paging system tailors the system for voice‑band intelligibility. The midrange control boosts the voice band (200 Hz to 7 kHz). Low and High band controls attenuate audio frequencies outside of the voice band. The center frequency of each of the three bands may be adjusted by +/‑ 12 dB. Note: The ST‑EQ3 is a cost‑effective module to enhance a variety of systems including adjustable “loudness” equalization for music in PA applications.

POWERING MULTIPLE SYSTEMS FROM ONE SUPPLY Remote ON/OFF Control Allows Users to Turn Systems On and Off
POWERING MULTIPLE SYSTEMS FROM ONE SUPPLY
Remote ON/OFF Control Allows Users to Turn Systems On and Off
AN-2172
Description:
The four separate sound systems are comprised of modules in the Equipment Rack powered by a single 24 Vdc power supply. Good engineering practice requires that the power wiring to each component originate at the power supply output. In this installation, the TX‑PD8X Switching Power Supply Distributor serves as the power source for the eight modules comprising the four systems. The TX‑PD8X is equipped with remote control terminals that provide for turning its eight outputs on or off. The wall‑mounted D‑RT2 Remote Control Selector allows users to control the TX‑PD8X, thereby turning the four systems on or off. Visual indication of the ON/OFF status is provided on the remote control. The TX‑PD8X is capable of distributing up to 2 Amps of 24 Vdc power to a maximum of eight dc power jacks from the corresponding RDL current‑limited switching power supply. A smaller RDL power supply may be used for systems with less total module current.

OBSERVATION ROOM AUDIO MONITOR Loudspeaker or Headphone Listening Station for Microphones Positioned in An Observation Room
OBSERVATION ROOM AUDIO MONITOR
Loudspeaker or Headphone Listening Station for Microphones Positioned in An Observation Room
AN-2223
Description:
Two microphones positioned in the observation room are preamplified and mixed by the ST‑MX2 audio mixer. The line‑level output of the mixer is amplified by the D‑HPA3 3.5 watt power amplifier to feed a D‑SP1A Decora‑Style loudspeaker. The D‑HPA3 includes a separate headphone amplifier. The speaker amplifier is set (rear‑panel switch) to mute the speakers when headphones are connected. The front‑panel volume knob controls both the power amplifier and the headphone amplifier level. The high‑impedance bridging input on the D‑HPA3 allows the audio output of the mixer to also feed a recording device.

BASIC CLASSROOM W/ INTEGRATED MIXER AMPLIFIER ON AV CART 35 Watt Mixer Amplifier Powers Portable Classroom Audio System
BASIC CLASSROOM W/ INTEGRATED MIXER AMPLIFIER ON AV CART
35 Watt Mixer Amplifier Powers Portable Classroom Audio System
AN-2131
Description:
This portable system provides robust amplification for portable speakers from multiple audio sources. Audio levels from a laptop computer, CD player and instructor's microphone can be independently adjusted on the HD‑MA35U, which also provides tone control to optimize audio for the room. The only active RDL component is the HD‑MA35U which powers up when audio is detected. When the system is inactive (no audio in use) it enters the sleep mode, consuming less than one watt for optimum energy conservation. The HD‑MA35U returns to active mode (turns on) automatically when an audio input becomes present.

PAGING DISTRIBUTION IN OFFICE COMPLEX Common Paging for Multi-Story Office Building
PAGING DISTRIBUTION IN OFFICE COMPLEX
Common Paging for Multi-Story Office Building
AN-2108
Description:
Installed UTP (unshielded CAT5, CAT6 or similar) cable can be used to distribute facility‑wide paging to multiple floors or zones. The facility paging source for this multiple story building is fed to the RDL TX‑TPS1A Active Single Pair Sender. Its output is fed to a twisted pair receiver on one floor, then in turn to additional receivers on the other floors. All connections use UTP terminated with RJ45 plugs. A TX‑TPR1A Active Single Pair Receiver on each floor delivers line‑level paging audio to the local amplifier. Each Format A twisted pair receiver bridges the UTP cable, allowing the source signal to continue on to multiple receivers. The receivers are powered from the TX‑TPS1A sender. (Note: If the total distances between the receivers exceeds the recommended cable length for the cable type used, one or more additional power supplies may be required. If needed, an additional power supply may be connected to any of the receiver modules. Consult the Format‑A twisted pair data, or RDL technical support for more information.)

PAGING DISTRIBUTION IN LARGE OFFICE COMPLEX Zoned Paging for Multi-Story Office Building
PAGING DISTRIBUTION IN LARGE OFFICE COMPLEX
Zoned Paging for Multi-Story Office Building
AN-2167
Description:
Installed UTP (unshielded CAT5, CAT6 or similar) cable is used to distribute facility‑wide paging to multiple floors or zones. The three paging sources for this multiple story building are fed to the RDL TX‑TPS3A Active Three Pair Sender. Its RJ45 output is fed to a twisted pair receiver on one floor, then in turn to additional receivers on the other two floors. By setting each TX‑TPR1A receiver to a different receive pair (A, B or C) each floor receives its own paging source. An All Call initiated at the main paging station will page all floors simultaneously. All connections use UTP terminated with RJ45 plugs. A TX‑TPR1A Active Single Pair Receiver on each floor delivers line‑level paging audio to the local amplifier. Each Format A twisted pair receiver bridges the UTP cable, allowing the source signal to continue on to multiple receivers. The receivers are powered from the TX‑TPS3A sender. (Note: If the total distances between the receivers exceeds the recommended cable length for the cable type used, one or more additional power supplies may be required. If needed, an additional power supply may be connected to any of the receiver modules. Consult the Format‑A twisted pair data, or RDL technical support for more information.)

AUTOMATICALLY SWITCHED PODIUM MICROPHONE Floor Mat Pressure Switch Mutes Microphone when Not in Use
AUTOMATICALLY SWITCHED PODIUM MICROPHONE
Floor Mat Pressure Switch Mutes Microphone when Not in Use
AN-2156
Description:
A podium microphone that is continuously left on can create an annoying “live” reverberant sound in many meeting rooms. This can be distracting before and after meetings and during breaks. This application shuts the microphone off when no one is at the podium, keeping the public address system quiet when no one is speaking. A commercially available floor mat security switch is placed behind the podium under a carpet mat (or under installed carpet for fixed podiums). When the presenter stands on the mat, its contact closure enables the audio output of the STM‑2X Switched Microphone Preamplifier that feeds the public address amplifier and speakers (not shown). Stepping off the mat releases the closure and mutes the microphone. The output of the STM‑2X provides both mic and line‑level outputs that may be wired balanced or unbalanced, making it compatible with any new or existing audio system. An EZ‑MCP1 Microphone Compressor is installed between the microphone and the STM‑2X to provide consistent audio levels from any presenter, and to avoid overloads that could produce distortion and clipping.

INTERCOM USING DECORA®-STYLE LOUDSPEAKERS Remote Decora Loudspeakers Serve Dual Duty as Microphone and Speaker
INTERCOM USING DECORA®-STYLE LOUDSPEAKERS
Remote Decora Loudspeakers Serve Dual Duty as Microphone and Speaker
AN-2240
Description:
Two RDL D‑SP1A Decora‑style wall‑mounted loudspeakers are used in this intercom system. The control station uses the speaker for monitoring. The remote station uses the D‑SP1A as both microphone and speaker, switched by an RDL ST‑LCR1 Logic Controlled Relay. Signal amplification and muting is provided by a pair of RDL ST‑IC1 Intercom Amplifiers. The D‑SP1A simplifies the physical installation and provides superior audio clarity to similarly‑sized loudspeakers. The control station is equipped with a push‑to‑talk microphone to control the direction of the conversation.

AUDIO DISTRIBUTION IN A LANGUAGE LAB Computer Audio, Instructor Microphone, Multiple Headphone Listening Stations
AUDIO DISTRIBUTION IN A LANGUAGE LAB
Computer Audio, Instructor Microphone, Multiple Headphone Listening Stations
AN-2019
Description:
In this system, a computer audio signal and a microphone signal are mixed using the RU‑MX4 Pro Audio Mic/Line Mixer. The mixed signal is distributed to multiple headphone listening stations in a language learning lab using an RU‑ADA4D Audio Distribution Amplifier. Each listening station features a D‑SH1 stereo headphone amplifier, which includes an integrated level control. Each D‑SH1 is mounted in a DC‑1G desktop chassis. The DC‑1G is constructed from steel and powder coated to provide years of durability in a classroom environment. The design of the D‑SH1 headphone amplifier makes it easy to create systems with an unlimited number of headphone listening stations. Either 1/4” or 1/8” (D‑SH1M) stereo headphone jack options are available. The system design is shown in mono but stereo configurations can be implemented just as easily.

AUTOMATIC POWERING OF CLASSROOM A/V SYSTEM Automatically Turn System On and Off to Conserve Energy and Simplify Operation
AUTOMATIC POWERING OF CLASSROOM A/V SYSTEM
Automatically Turn System On and Off to Conserve Energy and Simplify Operation
AN-2104
Description:
The RDL FP‑ECC1 Energy Conservation Controller provides the capability to automatically power up the classroom A/V electronics when needed and to power down the equipment when not in use to conserve energy and reduce operating costs. FP‑ECC1 “trigger” input bridges the mic signal from the room to switch or hold the system on. Then the presence of line‑level computer audio at the FP‑ECC1 “hold” input also keeps the system powered. After a switch‑selectable time period of 15, 30, or 60 minutes of no use, the FP‑ECC1 will turn off the system electronics. No operator intervention is needed to begin or end use of the system. Audio and video inputs from the room are fed through RDL wall plates. The D‑ECR1L Power On/Off and Remote Level Control allows users to manually power up/down the equipment controlled by the FP‑ECC1 Controller and to adjust the audio output from the amplifier. The D‑ECR1L matches the style of the other wall plates.

SINGLE ZONE AUTOMATIC PAGING LEVEL CONTROL Automatic Stepped Level Adjustment for Ambient Level Changes
SINGLE ZONE AUTOMATIC PAGING LEVEL CONTROL
Automatic Stepped Level Adjustment for Ambient Level Changes
AN-2034
Description:
The circuit shown is ideal in applications where paging levels are normally sufficient, but at times high ambient noise levels make the paging impossible to hear. This is common in school hallways which may be empty or crowded, making higher sound system levels necessary during periods of heavy congestion. Normal levels are restored when traffic is minimal. In this example, the STP‑1 Universal Audio Attenuator is used to set two audio levels (normal and high) for the line‑level audio feeding the power amplifier for the hallway. A sensing microphone is oriented to pick up ambient noise but not paging audio. Ambient noise triggers the ST‑ACR1M which switches the higher audio input level to the amplifier. When noise levels return to normal, the ST‑ACR1M switches back to the standard paging level. An RDL TX‑70A Speaker Level Interface can be added to obtain line‑level paging audio from a constant voltage speaker line.

FIXED MIXING OF PODIUM MIC AND LINE INPUTS Mixing a Microphone and Stereo Source to a Single Line
FIXED MIXING OF PODIUM MIC AND LINE INPUTS
Mixing a Microphone and Stereo Source to a Single Line
AN-2198
Description:
The sound system in this room is equipped with a mono balanced input from the floor box. When the podium is in use, the presenter uses the microphone and also uses an audio player or laptop computer. The ST‑UMX3 Universal Audio Mixer is installed to mix signals from a single dynamic microphone and the unbalanced stereo source located in the podium to a balanced mono mic‑level or line‑level (switch‑selectable) feed to the sound system input. The small size of the ST‑UMX3 allows it to be installed in the podium or the floor box. The ST‑UMX3 3X1 Universal Audio Mixer is used to combine signals of different level, impedance or balanced/unbalanced configuration. Each input and the output is switch‑selectable for mic or line level. Single‑turn trimmers are provided for the gain adjustment of each input.

NETWORKED AUDIO PAGING Multiple Paging Zones
NETWORKED AUDIO PAGING
Multiple Paging Zones
AN-2226
Description:
A Dante™ network is used to distribute several sources of facility‑wide paging to multiple buildings. Within each building (one is shown), networked audio is converted to RDL Format‑A for distribution to three floors using an RU‑NFD Network to Format‑A Interface/Distributor. Each paging source is routed to Format‑A Pair A, Pair B or Pair C through Dante Controller. The RU‑NFD provides three Format‑A output jacks that each send audio on pairs A, B & C to a twisted pair receiver on one floor, then in turn to additional receivers on the other two floors. By setting each TX‑TPR1A receiver to a different receive pair (A, B or C), each floor receives its own paging source. An All Call initiated at the main paging station will page all floors simultaneously. All connections use UTP terminated with RJ45 plugs. A TX‑TPR1A Active Single‑Pair Receiver on each floor delivers line‑level paging audio to the local amplifier. Each Format A twisted pair receiver bridges the UTP cable, allowing the source signal to continue on to multiple receivers. The receivers are powered from the RU‑NFD. (Note: If the total distances between the receivers exceeds the recommended cable length for the cable type used, one or more additional power supplies may be required. If needed, an additional power supply may be connected to any of the receiver modules. Consult the Format‑A twisted pair data, or RDL technical support for more information.)

RF SUPPRESSION IN AUDIO OR CONTROL CIRCUITS RFI Suppressed on Six Signal Conductors
RF SUPPRESSION IN AUDIO OR CONTROL CIRCUITS
RFI Suppressed on Six Signal Conductors
AN-2177
Description:
The ST‑FS6 Ferrite Suppressor / RF Filter is used to attenuate excessive RF interference (RFI) induced in the wiring conductors by a nearby communications tower. The passive ST‑FS6 provides six isolated channels of highly effective ferrite RF suppression without capacitance to ground or series resistance. Two ground terminals are provided to be used as tie points for connecting cable shields (not pictured). The ground lugs have no internal connection to the suppression circuitry. Each of the six I/O terminals may be used independently for the suppression of RF on Audio, dc power or logic control signal conductors. RF interference on audio and control wiring causes unwanted audio noise or instability in control circuits. The ST‑FS6 is normally installed at the rack where signals are received. It is possible that interference may interfere with audio or control sending equipment, making it beneficial to install a suppressor module at both ends of the long interconnection lines.

TWO MIC INPUTS FEED DANTE™ NETWORK OVER CATx Dual Mic Preamp Provides 48 V Phantom and Automatic Gain Setting
TWO MIC INPUTS FEED DANTE™ NETWORK OVER CATx
Dual Mic Preamp Provides 48 V Phantom and Automatic Gain Setting
AN-2239
Description:
The D‑TPSM2A Dual Microphone Preamplifier is installed in the meeting room for users to connect one or two wired microphones. The module provides 48 V phantom and is compatible with both dynamic and condenser microphones. Rear panel GAIN switches for each channel are set to AUTO by the installer to automatically provide 60 dB of gain for dynamic mics or 40 dB for condenser mics. The D‑TPSM2A output feeds the preamplified microphone signals to two Format‑A pairs. The output cable loops through a D‑TPSL1A interface which accepts a mono or stereo audio source that it sums to mono. The mono output from the D‑TPSL1A feeds the remaining Format‑A cable pair. The Format‑A cable terminates into an RU‑FN Format‑A to Network Interface module that converts the sources to three Dante network channels. The line‑level output of a wireless microphone receiver is connected to the Aux Input of the RU‑FN to feed its fourth Dante output channel. The Format‑A input modules are both powered from the RU‑FN. A single CATx cable run is the only installed cabling required for audio inputs in this meeting room

PAGING IN A MEETING ROOM WITH TWO SOURCES Paging Connected to a Remote Controlled Mixer with Twisted-Pair Input Modules
PAGING IN A MEETING ROOM WITH TWO SOURCES
Paging Connected to a Remote Controlled Mixer with Twisted-Pair Input Modules
AN-2087
Description:
The meeting room has two microphone inputs connected to an RDL FP‑TPX3A 2‑input mixer using twisted‑pair cable. Volume for each microphone is user‑adjusted on the wall‑mounted D‑RC2M which is also connected to the mixer using twisted‑pair cable. The third input of the FP‑TPX3A is used as the balanced, line‑level paging input. The paging level is set at the mixer so it cannot be turned down or off by a user in the meeting room. The FP‑TPX3A allows user remote control of the local inputs while maintaining a fixed level for the facility priority paging. The use of standard twisted pair cabling using RJ45 connectors cuts both installation time and cost.

BASIC CLASSROOM W/ INTEGRATED MIXER AMPLIFIER ON AV CART Microphone, Laptop Audio, DVD Player, 20 Watt Mixer Amplifier
BASIC CLASSROOM W/ INTEGRATED MIXER AMPLIFIER ON AV CART
Microphone, Laptop Audio, DVD Player, 20 Watt Mixer Amplifier
AN-2015
Description:
The EZ‑MXA20 provides a microphone preamp, mixer, limiter, tone control, and a stereo power amplifier in a package less than six inches wide. The EZ‑MXA20 handles sound reinforcement whether the audio source is a computer, DVD player, live presenter, or all three. The power amplifier provides 10 Watts per channel into 8 Ohm speakers or 8 Watts per channel into 4 Ohm speakers. Bass and treble tone controls provide equalization of source material. The limiter controls overloads from clipping the amplifier and an LED on the front panel of the EZ‑MXA20 indicates when the limiter is active.

TABLE-TOP PRESENTATION PERSONAL MONITOR SYSTEM Automatic Attenuation Avoids Feedback Between Pick-Up Mic and Monitor Speaker
TABLE-TOP PRESENTATION PERSONAL MONITOR SYSTEM
Automatic Attenuation Avoids Feedback Between Pick-Up Mic and Monitor Speaker
AN-2205
Description:
This sound system is designed to provide clear communication between two presenters and an assembled group. The two presenter positions are each equipped with a table‑top microphone and loudspeaker. The loudspeakers allow the presenters to clearly hear questions from the audience as well as each other. The audience microphone and the two presenter microphones are mixed in the rack; a line‑level signal feeds the amplifiers for the house and the table‑top loudspeakers. Each RDL ST‑GSP1 Gated Speech Preamplifier provides an automatically‑switched line‑level output from a microphone. When an ST‑GSP1 preamplifier is gated ON, the SLAVE (open‑collector) output mutes its associated ST‑MA2 Monitor Amplifier (and RU‑SP1 Monitor Speaker) and attenuates the adjacent monitor speaker, thereby preventing feedback. (Terminals on the ST‑MA2 can MUTE or provide 3 dB or 6 dB of attenuation while pulled to ground, permitting this wiring method to be expanded to multiple presenter stations.)

POWERING MULTIPLE STICK-ONS FROM SINGLE SUPPLY Distributed dc Power From Current-Limited Switching Power Supply
POWERING MULTIPLE STICK-ONS FROM SINGLE SUPPLY
Distributed dc Power From Current-Limited Switching Power Supply
AN-2193
Description:
The low current consumption of STICK‑ON modules allows multiple modules to be powered from a single supply. The ST‑PD5U distributes power from any RDL current‑limited switching power supply to up to five modules with a total current requirement of 2 amperes or less. RDL 24 Vdc switching power supplies (purchased separately) are available with current ratings of 500 mA, 1 A and 2 A. All meet ENERGY STAR Level V standards.

PRIORITIZED PAGING Voice-Over/Paging with Multiple Paging Sources
PRIORITIZED PAGING
Voice-Over/Paging with Multiple Paging Sources
AN-2010
Description:
In this application several RDL modules are used to create a multiple priority paging system. A local audio source can be overridden by an Emergency Alert System (EAS). Either source is overridden by the School Wide Paging source. The local source from the laptop is fed into a DS‑CIJ3 input plate to provide a balanced mono output to the “Music” input of an ST‑VP1 Voice‑ Over Paging Module and passes thru the unit under normal operating conditions. The EAS line level audio is fed to the “Voice” input on the ST‑VP1. A contact closure from the EAS receiver causes the ST‑VP1 to switch from the “Music” audio input to the “Voice” audio input. The output of the first ST‑VP1 will feed the “Music” input of a second ST‑VP1 to allow override by the highest priority source. An RDL STM‑2 mic preamp provides the line level signal to the “Voice” input of the second ST‑VP1. PTT contacts switch from the “Music” input to the “Voice” input to give this microphone the highest priority. The output of the second ST‑VP1 feeds RDL’s FP‑PA20A 70 V amplifier and associated 70 V loudspeakers.

ELIMINATE AUDIO HUM IN A GROUP PRESENTATION Galvanic Isolation for Stereo Audio Ground Loop or Computer Digital Noise
ELIMINATE AUDIO HUM IN A GROUP PRESENTATION
Galvanic Isolation for Stereo Audio Ground Loop or Computer Digital Noise
AN-2084
Description:
Presentations using a laptop computer face problems of delivering quality audio through an unbalanced connection. Any difference in ground potential between the computer and audio amplifier creates “hum” that becomes part of the presentation audio. In some systems, digital noise from the computer may also add a constant irritating background noise to the audio. The RDL AV‑HK1 easily solves this common problem. The AV‑HK1 breaks the ground path for “hum” and ditigal noise using stereo audio isolation transformers in a rugged, tightly shielded enclosure. The AV‑HK1 “Hum Killer” is a must‑have item for the touring presenter and is equally useful in a fixed AV installation.

SEND UNBALANCED AUDIO OVER A LONG DISTANCE Balanced Audio Connections Between Stereo Unbalanced Devices
SEND UNBALANCED AUDIO OVER A LONG DISTANCE
Balanced Audio Connections Between Stereo Unbalanced Devices
AN-2095
Description:
Unbalanced audio is not suited to long distance transmission due to susceptibility to hum and ground loops. This problem is avoided by balancing the audio source prior to transmission and by isolating the received signals with effective common mode (hum) rejection. This application uses an RDL STA‑2A Dual Line Amplifier to boost the unbalanced stereo source up to the standard +4 dBu level to drive a pair of balanced lines. The balanced lines may be shielded or unshielded (UTP) and may be up to several hundred feet long. An RDL TX‑A2D Dual Audio Converter receives the balanced audio, converts it to unbalanced and attenuates it to a standard ‑10 dBV level feeding RCA output jacks. Studio quality audio transformers in the TX‑A2D provide very high common‑mode hum rejection and galvanic isolation from the balanced lines. The received remote source is connected to one of the stereo unbalanced inputs of an RDL EZ‑MX4L stereo audio mixer that feeds the conference room amplifiers and speakers.

SCHOOL AUDIO/PAGING SYSTEM School Paging Interrupts Classroom Audio
SCHOOL AUDIO/PAGING SYSTEM
School Paging Interrupts Classroom Audio
AN-2058
Description:
This system uses a TX‑PCR1 Paging Controlled Relay to interrupt classroom audio to allow a page to be heard clearly. Classroom audio is fed through a wall plate to the 70 Volt amplifier. The 70 V speaker ouput is routed through normally closed contacts of the paging controlled relay to the clasroom speakers. The paging controlled relay samples the 70 V audio to the classroom paging speaker. Whenever school‑wide paging is active the relay is energized and the classroom audio is interrupted. This allows the page to be heard without interference from the classroom audio. The wall plate used in this example is available in the normal RDL grey/white or in stainless steel with custom labeling available.

CLASSROOM W/ PROJECTOR AUDIO/VIDEO SWITCHING Computer, Auxiliary Input, Projector w/ variable output, 40 Watt Stereo Audio Amplifier
CLASSROOM W/ PROJECTOR AUDIO/VIDEO SWITCHING
Computer, Auxiliary Input, Projector w/ variable output, 40 Watt Stereo Audio Amplifier
AN-2046
Description:
This classroom is equipped with a computer and with jacks for an auxiliary audio/video source such as a DVD player or VCR. The computer is connected to a jack plate at the front of the room. The auxiliary input is shown at the rear. Audio and video from each of the audio/video input plates is connected to the projector using standard audio wiring and monitor cables. The projector is used to switch between sources and to control the audio level to the speakers. The projector must be equipped with a variable level audio output. Each output channel of the power amplifier powers two 8 Ω speakers. All wall controls and panels are offered in RDL standard white/gray or in stainless steel with custom labeling available.

OBSERVATION ROOM AUDIO MONITOR Loudspeaker or Headphone Listening Station for Microphones Positioned in An Observation Room
OBSERVATION ROOM AUDIO MONITOR
Loudspeaker or Headphone Listening Station for Microphones Positioned in An Observation Room
AN-2218
Description:
Two microphones positioned in the observation room are preamplified and mixed by the ST‑MX2 audio mixer. The line‑level output of the mixer is amplified by the D‑HPA3 3.5 watt power amplifier to feed a wall‑mounted loudspeaker. The D‑HPA3 includes a separate headphone amplifier. The speaker amplifier is set (rear‑panel switch) to mute the speakers when headphones are connected. The front‑panel volume knob controls both the power amplifier and the headphone amplifier level. The high‑impedance bridging input on the D‑HPA3 allows the audio output of the mixer to also feed a recording device.

CORPORATE CONFERENCE/PRESENTATION CENTER Laptop Audio, Wireless Mic System, 3 Channel Mixing with 20 Watt Amplifier
CORPORATE CONFERENCE/PRESENTATION CENTER
Laptop Audio, Wireless Mic System, 3 Channel Mixing with 20 Watt Amplifier
AN-2018
Description:
The EZ‑MXA20 provides a microphone preamp, mixer, limiter, tone control, and a stereo power amplifier in a package less than six inches wide. The EZ‑MXA20 handles sound reinforcement whether the audio source is a computer, CD player, live presenter or all three. The power amplifier provides 10 Watts per channel into 8 Ohm speakers or 8 Watts per channel into 4 Ohm speakers. Bass and treble tone controls provide equalization of source material. The limiter controls overloads from clipping the amplifier and an LED on the front panel of the EZ‑MXA20 indicates when the limiter is active.

CLASSROOM WITH INTEGRATED MIXER AMPLIFIER Simple Constant Voltage Classroom Sound System
CLASSROOM WITH INTEGRATED MIXER AMPLIFIER
Simple Constant Voltage Classroom Sound System
AN-2137
Description:
The RDL HD‑MA35UA 35 Watt Mixer Amplifier is a full‑featured, four input mixer amplifier that can be readily desk mounted. The optional RDL HD‑BP1 Back‑Pack Rear Cover is designed to conceal and secure connections to the amplifier. When the system is not in use, the HD‑MA35UA enters sleep mode and consumes less that 1 Watt to effectively save power and reduce operating costs. The amplifier automatically turns back on (active mode) whenever audio is detected at any input. This classroom makes use of computer and DVD audio sources as well as a microphone. The HD‑MA35UA constant voltage (25 V, 70 V or 100 V) amplifier has sufficient power to enable proper loudspeaker distribution throughout the classroom allowing for even coverage and high intelligibility.

COMBINE THREE SOURCES ON ONE FORMAT-A PAIR Expand the Capacity of a Format-A Cable Run Using a Three-Pair Combiner
COMBINE THREE SOURCES ON ONE FORMAT-A PAIR
Expand the Capacity of a Format-A Cable Run Using a Three-Pair Combiner
AN-2232
Description:
The TX‑TPSA1A Three‑Pair Combiner to Single‑Pair Sender is used to add up to two additional sources to one pair in a Format‑A system. Each of the three D‑TPS1A single‑pair microphone senders is set to feed a unique pair (A, B or C). These senders are daisy chained on one CATx cable run connected to the INPUT of the TX‑TPSA1A combiner where the three pairs are summed to feed Pair A. Two D‑TPSL1A single‑pair senders (set to feed pairs B and C) are looped together on a second cable run connected to the LOOP IN of the combiner. All three pairs are present at the OUTPUT which can be connected to any RDL Format‑A receiver, distributor or compatible Dante interface. DC power connected to the TX‑TPSA1A powers all five senders. Note: Up to three TX‑TPSA1A modules may be daisy chained on one cable run, permitting as many as nine senders to feed audio through a single Format‑A cable (three sources on each pair A, B and C)

AUDIO SOURCE SELECTION & LEVEL CONTROL Multiple Control Locations in a Multi-Purpose Meeting Room / Auditorium
AUDIO SOURCE SELECTION & LEVEL CONTROL
Multiple Control Locations in a Multi-Purpose Meeting Room / Auditorium
AN-2212
Description:
The multi‑purpose room is provided with four different line‑level audio sources. Users of the room are able to select their desired source and adjust the audio level from within the space. The RU‑ASX4DR Remote Controlled Audio Selector with VCA is controlled by two D‑RC4M Four Channel Remote Controls (source selectors) and two D‑RLC10 Remote Level Controls (0 to 10 Vdc). Two control locations are shown; up to ten remote locations are possible. All sources may be muted by de‑selecting the active input on either D‑RC4M. The D‑CIJ3D Consumer Interface Jack Panel is used for connection of a user‑supplied audio source.

SEQUENCE LOW VOLTAGE DC POWER AND AMPLIFIERS Eliminate Audio Pops During System Power-Up and Power-Down
SEQUENCE LOW VOLTAGE DC POWER AND AMPLIFIERS
Eliminate Audio Pops During System Power-Up and Power-Down
AN-2173
Description:
The RU‑SQ6A Sequencing Controller provides complete power distribution management in this sound system. Sequencing the power ON and OFF of the system avoids annoying and sometimes damaging thumps and pops by turning power amplifiers ON last and OFF first. In systems using large power amplifiers, the sequencing of power can also avoid high inrush currents during power up. The RU‑SQ6A features outputs for six sequential steps. The Timing Interval between steps may be adjusted between 1 and 10 seconds. Each step is provided with both Open Collector and SPST dry contact outputs. In this application Open Collector outputs are used to activate the TX‑PD8X Switching Power Supply Distributors that power numerous other RDL products while dry contact closures are used to activate OEM low voltage controllable mains power outlets. Remote ON/OFF control of the RU‑SQ6A is provided by a D‑RT2 Remote Control Selector. Visual indication of the ON/OFF status is provided on the remote control.

AUTOMATIC PROJECTOR SCREEN CONTROL Projector On/Off Status Converted to Up/Down Pulses to Control Motorized Projection Screen
AUTOMATIC PROJECTOR SCREEN CONTROL
Projector On/Off Status Converted to Up/Down Pulses to Control Motorized Projection Screen
AN-2186
Description:
Used with a projector that provides a contact closure or logic‑level voltage when powered on, the ST‑LCR3 Logic Controlled Relay provides a momentary contact closure to automatically lower the motorized projection screen. When the projector is powered off, the ST‑LCR3 provides a separate momentary contact closure to raise the screen. Additional ST‑LCR series modules may be triggered by the ST‑LCR3 SLAVE outputs to provide additional contact closures to control window shades and lighting presets for complete single‑button control of an AV system.

BASIC CLASSROOM WITH PROJECTOR Computer, Projector w/ variable output, 40 Watt Stereo Audio Amplifier
BASIC CLASSROOM WITH PROJECTOR
Computer, Projector w/ variable output, 40 Watt Stereo Audio Amplifier
AN-2047
Description:
This classroom is equipped with a computer, projector and overhead speakers. The computer is connected to a jack plate at the front of the room. Audio and video from the audio/video input plate is connected to the projector using standard audio wiring and monitor cable. The projector is used to control the audio level to the speakers. The projector must be equipped with a variable level audio output. Each output channel of the power amplifier powers one 8 Ω speaker. All wall controls and panels are offered in RDL standard white/gray or in stainless steel with custom labeling available.

ELIMINATE AUDIO HUM IN MEETING ROOM OR CLASS ROOM Galvanic Isolation for Audio “Ground Loop”
ELIMINATE AUDIO HUM IN MEETING ROOM OR CLASS ROOM
Galvanic Isolation for Audio “Ground Loop”
AN-2096
Description:
A laptop computer that is connected to AC power typically produces a “ground loop” if its audio output is connected to an installed sound system. The difference in ground voltage between the computer and equipment rack amplifier causes a hum in the audio signal. Small “ground loop” voltages can produce high audio hum levels from the speakers. Installing the RDL EZ‑HK1 between the computer and the system input removes the “ground loop” using a stereo pair of high quality audio transformers in a shielded metal enclosure. The input jacks are ground‑isolated. A ground‑lift switch allows the output jack shields to be lifted from the metal chassis if required. Audio connections are easy to interface between jack types. The EZ‑HK1 input provides both stereo RCA jacks and a stereo mini‑jack. The output also is provided on stereo RCA jacks or a stereo mini‑jack.

AMPLIFICATION FOR OUTDOOR POLE-MOUNT SPEAKERS Pole Mounted Power Amp Operation in Extreme Temperatures
AMPLIFICATION FOR OUTDOOR POLE-MOUNT SPEAKERS
Pole Mounted Power Amp Operation in Extreme Temperatures
AN-2125
Description:
This outdoor parking area is equipped with speakers mounted in the lamp structures to provide music and paging coverage. Speakers in each pole are powered by an RDL FP‑PA18H 18 Watt Hi‑Temp Audio Amplifier. The amplifier module is mounted in an unventilated watertight enclosure at the base of each pole. The poles recieve direct sunlight causing the potential for high internal ambient air temperatures. The highly efficient FP‑PA18H is ideally suited to this environment. It is designed for operation in ambient temperatures up to 70 degrees Celsius (about 158 degrees Fahrenheit) and contributes negligible heat to the ambient temperature inside the pole. The amplifier’s integral compressor/limiter insures maximum intelligibility by keeping average power levels high and preventing clipping. The FP‑PA18H combines RDL's high audio performance standards with the capability of operation in harsh temperature environments. Notes: 1] If it is desired to monitor the operation of the complete system, the audio detector included in each FP‑PA18H can be wired back to the system audio rack to confirm that audio is being received and amplified at each pole. 2] If the FP‑PA18H is acquired with an RDL power supply, that supply must be located in an ambient environment not to exceed 40 degress C. FP‑PA18H modules are available without a power supply for use with high temperature supplies or in systems using distributed 24 Vdc power. Contact RDL Technical Support for more information.

CLASSROOM SYSTEM WITH PRIORITIZED PAGING Full-Featured “Green” Mixer Amp Integrates Two Paging Priorities
CLASSROOM SYSTEM WITH PRIORITIZED PAGING
Full-Featured “Green” Mixer Amp Integrates Two Paging Priorities
AN-2133
Description:
Classroom mic, line and computer audio sources are connected to the HD‑MA35UA Mixer Amplifier through RDL wall plates. A school‑wide paging feed connects directly to the mixer amplifier paging input. The paging source may be either mic or line level. VOX switching eliminates the need for push‑to‑talk contacts. The HD‑MA35UA setup allows flexibility in muting or ducking the other input channels during paging. An ST‑VP2 Automatic Ducking Module adds an additional priority paging source. The ST‑VP2 uses the HD‑MA35UA effects loop to cause the highest priority page message to duck all other amplifier inputs to provide the emergency page. The ST‑VP2 is powered by the auxiliary module 24 Vdc power output from the HD‑MA35UA. The HD‑MA35UA powers up when audio is detected. When the system is inactive (no audio in use) it enters the sleep mode, consuming less than one watt for optimum energy conservation. The HD‑MA35UA returns to active mode (turns on) automatically when an audio input becomes present.

TWO ZONE PAGING SYSTEM Remote Switch at Paging Station Controls Solid-State Audio Routing to Proper Paging Zone
TWO ZONE PAGING SYSTEM
Remote Switch at Paging Station Controls Solid-State Audio Routing to Proper Paging Zone
AN-2192
Description:
The operator of the paging station can selectively page in either zone. The STM‑2X Switchable Low Noise Microphone Preamplifier amplifies the paging mic to line level. The preamp output is active only while the operator presses the mic push‑to‑talk button. The ST‑RX2 Audio Routing Switcher routes the line‑level audio signal to one of the two amplifiers. The NORMAL output feeds the Zone 1 amplifier; the SELECT output feeds Zone 2. The Audio Routing Switch at the operator’s station controls the ST‑RX2 TRIG terminal. When the ST‑RX2 TRIG control terminal is not connected to ground, audio is fed to the NORMAL output and the SELECT output is turned off. When the TRIG control terminal is grounded, the input audio is routed to the SELECT output and the NORMAL output is muted.

FORMAT-A SOURCE SELECTOR & IN-WALL AMPLIFIER Distribute Three Audio Sources to Multiple Locations Over UTP Cable
FORMAT-A SOURCE SELECTOR & IN-WALL AMPLIFIER
Distribute Three Audio Sources to Multiple Locations Over UTP Cable
AN-2224
Description:
Three styles of music are distributed to various rooms in this facility over CAT 5 cable by an RU‑TPS4A Format‑A Active Sender / Distributor. A D Series‑TPRX3A Source Selector, D Series‑PA3 Audio Amplifier and D SERIES‑SP1A 8 Ohm loudspeaker installed in each room allow the occupants to listen to any of the three types of music provided or to listen to their own program material simply by plugging their MP3 player into the front‑panel input on the D‑PA3 amplifier. The front‑panel local input overrides the distributed audio. The D‑SP1A loudspeaker provides rich detailed sound in a compact Decora compatible format.

FORMAT-A SOURCE SELECTOR & IN-WALL AMPLIFIER Distribute Three Audio Sources to Multiple Locations Over UTP Cable
FORMAT-A SOURCE SELECTOR & IN-WALL AMPLIFIER
Distribute Three Audio Sources to Multiple Locations Over UTP Cable
AN-2220
Description:
Three styles of music are distributed to various rooms in this facility over CAT 5 cable by an RU‑TPS4A Format‑A Active Sender / Distributor. A D Series‑TPRX3A Source Selector and D Series‑PA3 Audio Amplifier installed in each room allow the occupants to listen to any of the three types of music provided or to listen to their own program material simply by plugging their MP3 player into the front‑panel input on the D‑PA3 amplifier. The front‑panel local input overrides the distributed audio.

LONG DISTANCE TWISTED-PAIR VIDEO MONITORING Camera at Top of Ski Lift Monitored at Ski Lodge Security Office
LONG DISTANCE TWISTED-PAIR VIDEO MONITORING
Camera at Top of Ski Lift Monitored at Ski Lodge Security Office
AN-2114
Description:
The security camera at the top of the ski lift feeds an RDL TX‑TPS1C Active Three Pair Sender. At the end of about one mile of twisted pair cable, a TX‑TPR3C Twisted Pair Receiver feeds the video monitor in the security office. The TX‑TPR3C is set to terminate the twisted pair cable. GAIN and EQ controls are adjusted to compensate for cable losses. Note: Two audio pairs are also available on the RDL Format C modules. No audio is shown in this application; the audio channels could be used to provide talk‑back capability from the upper lift operator station.

AUDIO DISTRIBUTION TO MULTIPLE HEADPHONE AMPS Computer Audio Feeds Multiple Headphone Listening Stations Over Format-A Twisted Pair Cable
AUDIO DISTRIBUTION TO MULTIPLE HEADPHONE AMPS
Computer Audio Feeds Multiple Headphone Listening Stations Over Format-A Twisted Pair Cable
AN-2163
Description:
The laptop computer provides the stereo audio source to be distributed to eight headphone listening locations. Line‑level audio from the computer is connected to a wall‑mounted DS‑TPS2A Active Two‑Pair Sender. The DS‑TPS2A sender converts the computer audio to Format‑A for transmission over CAT‑5 (or better) cable to the RU‑TPS4A Active Distributor. The RU‑TPS4A has 4 outputs, each capable of distributing the audio to as many as six headphone listening stations, for a total of 24. In this installation, two outputs are used feeding four headphone amplifiers per output, for a total of eight. Each listening station features a D‑HA1A Stereo Headphone Amplifier, which includes an integrated user level control and a 3.5 mm mini‑jack output. Each D‑HA1A is mounted in a DC‑1G Desktop Chassis. The DC‑1G is constructed of steel and is powder coated to provide years of durability in a classroom or other high traffic environment. Power (24 Vdc) connected to the RU‑TPDA is distributed to all the modules in the system. The RU‑TPDA may be rack mounted.

CLASSROOM REMOTE CONTROLLED MIXER-AMP Full-Featured “Green” Amplifier Saves Energy and Reduces Operating Costs
CLASSROOM REMOTE CONTROLLED MIXER-AMP
Full-Featured “Green” Amplifier Saves Energy and Reduces Operating Costs
AN-2130
Description:
The wall‑mounted D‑RC3M allows full remote‑controlled mixing and muting of the audio sources. Computer, DVD/VCR and wireless microphone sources are connected through RDL wall plates permitting energy‑saving passive CAT5/6 and monitor cable interconnection to the amplifier and projector. Video sources are selected by the projector. The HD‑RA35UA drives 70V constant voltage speakers (or 25V if preferred or required by local code) for placement of multiple speakers for optimal audio coverage. The only active RDL component is the HD‑RA35UA Mixer Amplifier which “powers up” as soon as it detects audio. When the system remains inactive (no audio in use), the HD‑RA35UA enters the sleep mode, consuming less than one watt for optimum energy conservation. The HD‑RA35UA returns to active mode (turns on) automatically when an audio input becomes present.

FIXED MIXING OF PODIUM MIC AND LINE INPUTS Mixing a Condenser Microphone and Stereo Source to a Mono Line
FIXED MIXING OF PODIUM MIC AND LINE INPUTS
Mixing a Condenser Microphone and Stereo Source to a Mono Line
AN-2202
Description:
The sound system in this room is equipped with a mono balanced input from the floor box. When the podium is in use, the presenter uses the condenser microphone and also uses an audio player (or laptop computer) in the podium. The ST‑MPA48 provides the P48 phantom voltage for the condenser microphone. The three inputs on the ST‑UMX3 Universal Audio Mixer mix the microphone with the left and right unbalanced audio player outputs. The ST‑UMX3 provides a balanced mono mic‑level or line‑level (switch‑selectable) feed to the sound system input. The small size of the ST‑UMX3 and the ST‑MPA48 allows them to be installed in the podium or the floor box. The ST‑UMX3 3X1 Universal Audio Mixer is used to combine signals of different level, impedance or balanced/unbalanced configuration. Each input and the output is switch‑selectable for mic or line level. Single‑turn trimmers are provided for the gain adjustment of each input. The ST‑MPA48 contains two identical phantom power circuits and a common power supply input. If only one mic input is to be converted for phantom operation, only one circuit needs to be used. Phantom voltage is not present on the output terminals.

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