Product Applications

1.) 0 to 5Vdc with RLC-3 Controller
This application allows the RLC3 to control modules that require 0 to 5Vdc control with 4 presets.

2.) 2 ZONE NOISE MASKING SYSTEM
This application shows the layout of a 2 zone noise masking system. The white noise line output from the RDL ST-NG1 feeds the inputs of two RDL FP-PEQ3 parametric equalizers.

3.) 4 Studios with Talkback
This application will allow the master location the ability to talk to all studios and select which studio is heard by the master location.

4.) ADDING SLAVE RELAYS

5.) Automatic Audio System Shut-off
This application was made for turning the audio system off when it is not being used.

6.) AUTOMATIC LEVEL ADJUSTMENT FOR AMBIENT NOISE
This application is used for automatic level adjustment for ambient noise.

7.) AUTOMATIC STAGE MONITOR NOISE REDUCTION
Audio monitor speaker signals often contain unwanted noise that is distracting to performers between musical selections or when the monitors are not in use. Examples include ambient pickup from live microphones or hum from instruments. During these periods when performers are not actively listening to the monitors, the RDL ST-GLA1 (use 2 for stereo as shown) mutes the audio signal to the monitor amplifier(s). The muting threshold is adjusted on the module to activate the audio for valid signal levels. The monitors will be muted at all other times. This application may be used in installations using either fixed or portable monitor speakers. It is ideal for church choir monitors or any performance area using stage monitors.

8.) AUTOMATIC STEPPED LEVEL ADJUSTMENT FOR AMBIENT LEVEL CHANGES
The circuit shown is ideal in applications where paging signals into a power amplifier are normally OK, but at times a high ambient noise level makes the paging impossible to hear. This would be common in a factory setting where heavy machinery is in use at some times, making higher sound system levels necessary while the machinery is operating then again restoring the level to normal when the machinery is no longer operating.

9.) Background Music & Paging System
This application gives the user voice-over paging and telephone paging in selected zones and background music with remotely controlled volume.

10.) CONDUCTORS TO CONNECT TWO LOCATIONS
The ST-TC1 provides biasing for operating a standard telephone, a circuit for detecting "off hook" condition, a transformer coupled output, and DPDT relay contacts which switch when "off hook" is detected. These features may be used to develop a "silent ring" intercom system for use in stage and studio environments where an audible ring would not be acceptable.

11.) CROSS-FADER
This application allows the user to select either source 1 or source 2 using the RDL RC2-ST. When either source is selected, the selected source will fade up while the other source fades down.

12.) Cross-Fader
This application allows the user to select either source 1 or source 2 using the RC2-ST. When either source is selected, the selected source will fade up while the other source fades down

13.) EXTENDING ST-ACR RELEASE DELAY
This circuit is designed to extend the release delay time of the ST-ACR1, or ST-ACR2. This is intended primarily for silence sensing where a longer delay is required.

14.) GROUND-LOOP SUPPRESSION
For optimum, correct facility performance, good engineering practice dictates that audio line-level interconnections between facilities be made using balanced lines.

15.) INSTRUCTOR WORKSTATION VOLUME CONTROL
This application demonstrates one way of configuring an audio system using a computer workstation for instructional presentations. The audio level is controlled by an RDL ST-VCA2 and an RDL RLC10K remote control. The speakers are powered by two RDL ST-PA6s. The RLC10K may be mounted in any convenient location (desktop, podium or wall mounted) giving the instructor direct volume control of the audio system level. Note: The RDL SR-4 enclosure may be used to conveniently mount all the modules.

16.) INTERCOM USING SINGLE REMOTE SPEAKER

17.) INTERCOM USING TWO STANDARD TELEPHONES
This application shows a two phone system. The ST-TC1 provides biasing for operating a standard telephone, a circuit for detecting “off hook” condition, a transformer coupled output, and DPDT relay contacts which switch when “off hook” is detected. These features may be used to develop a “silent ring” intercom system for use in stage and studio environments where an audible ring would not be acceptable. Each telephone instrument requires a single ST-TC1. A twisted pair connects audio between the two modules. The additional pairs carry the annunciation (lamp, flasher, etc.) actuation closure. The annunciation device is active whenever the opposite phone is “off hook”.

18.) ISOLATED MEDIA FEEDS
With the proliferation of TV news coverage, cable channel coverage, and audio recording, many sound systems require having available output jacks. As these must accomodate a variety of users, some with mic level inputs, some with line level inputs, and some balanced while others are unbalanced, interfaces must be provided. Not only must the interface provide a variety of outputs, it must also isolate those outputs from each other, and even more importantly from the power amplifiers in the sound system! Stick-Ons™ provide the ideal solution to having a variety of isolated audio signals to drive a variety of audio jacks on a “Media” panel. The drawing is an example where a line-level signal must drive both mic and line level outputs on RCA, phone, and XLR jacks. Even if a user inadvertantly plugs his output into a jack, that signal is isolated both from the other jacks and from the total sound system! In this example, the attenuation of the RDL STP-1 “A” channel should be set to maximum loss. Set the “B” channel about mid-way, then the “GAIN” pot on the RDL STM-DA3 can be adjusted for normal mic levels.

19.) ISOLATED MEDIA FEEDS
With the proliferation of TV news coverage, cable channel coverage, and audio recording, many sound systems require having available output jacks. As these must accomodate a variety of users, some with mic level inputs, some with line level inputs, and some balanced while others are unbalanced, interfaces must be provided.

20.) Jukebox Over-rides Background Sources
Use the ST-ACR2 to switch between a Jukebox audio source, and any other audio source such as a Radio, TV or Satellite Receiver.

21.) MIX-MINUS
The "Post-Fader" signal and the Final Mix signal must be connected out-of-phase to the inputs of the ST-MX3. Then adjust the input gain pots on the ST-MX3 to null-out the unwanted signal from the final mix.

22.) Mixing multiple phantom powered mics
Mixing multiple phantom powered mics is often desirable in various stage, church and conferencing installations. The STD-150 mixes the mic signals equally and passes phantom voltage generated in the mic preamp to each of the mics.

23.) MIXING WIRELESS AND WIRED MICROPHONES
Meeting rooms are often equipped with standard wired microphones that can be mixed using the RDL RU-MX4. The addition of wireless microphones to the usual complement of wired mics requires additional inputs on the mixer.

24.) MOMENTARY START/STOP CLOSURES
When the "CONTROL" relay closes, the "START" relay will pulse "ON" then "OFF". When the "CONTROL" relay re-opens, the "STOP" relay will pulse "ON" then "OFF". Therefore, you get a "START" momentary closure at the beginning of a logic input.

25.) PHANTOM POWERING A MIC PREAMP AT A REMOTE LOCATION USING ONLY A SINGLE TWISTED PAIR
This application is designed for paging mic operation from a remote location where only a single twisted pair is available. The single pair is used to feed power to the remote STM-1, and to return the line-level audio for the system. The audio feed is kept balanced, and there is no DC "-" connection to ground, which could cause high levels of induced noise in the twisted pair.

26.) PHONE ON/OFF-HOOK CONTACTS
This circuit provides relay activation when the phone is placed on-hook or off-hook. The relay in the ST-LCR1 is a DPDT unit so either a contact closure or opening may be used. The relay is normally activated when the phone is on-hook.

27.) PRIORITIZED PAGING
This application is designed to permit multiple paging locations, with priority assigned to each location. Each location has a mic and a push-to-talk momentary pushbutton. The STM-2 preamp for each mic should be located where the mic is installed. Wiring between the STM-2 output and the ST-LCR1 should be BALANCED if the amplifier being used has a balanced input circuit (2 conductors + shield).

28.) PRIORITIZIED PAGING
This application is designed to permit multiple paging locations, with priority assigned to each location. Each locations has a mic and a push-to-talk momentary pushbutton.

29.) PUSH-TO-TALK INTERCOM
Intercom installations are often manually controlled from a master position. The master station is equipped with a microphone for optimum intelligibility as well as a momentary push-to-talk button (RDL’s AMS-PB1 is shown.) Communication is based on a pair of RDL ST-IC1 Intercom Amplifiers. If the secondary location is equipped with a microphone, no additional modules are required. The secondary location speaker may serve as a microphone by adding an RDL ST-LCR1. The master location speaker monitors the secondary location audio whenever the button is not pushed. An RDL SR-4 Mounting Frame can provide convenient mounting.

30.) RELAY CONTACT CLOSURE TRIGGERED FROM A SPEAKER LINE
The presence or absense of audio from an amplified speaker line often needs to control other equipment. The RDL ST-ACR1 can provide either a normally open or normally closed contact when audio is present. Since the ST-ACR1 is triggered from a line level source, detecting amplified audio requires an input attenuator. For a standard 8 Ohm speaker line, an RDL STP-1 may be used. For a constant voltage speaker line (25, 70 or 100 V), an RDL TX-70A provides isolation and adjustable attenuation for reliable triggering of the ST-ACR1. The relay contacts will be closed and the SLAVE terminal will be pulled to ground when audio is present.

31.) Remote Level Controlled System
This application allows a portable DJ rack to have remote access to the controls for EQ and volume while concealing the actual modules.

32.) REMOTE STAGE MONITOR NOISE REDUCTION
Audio monitor speaker signals often contain unwanted noise that is distracting to performers between musical selections or when the monitors are not in use. Examples include ambient pickup from live microphones or hum from instruments. During periods when it is desired to mute the monitors, users may manually turn them off using the RDL ST-SSR1 solid-state audio switch module (use 2 for stereo as shown). The RDL RT-2 remote control may be mounted in any convenient location (podium mounted, wall mounted). This application may be used to mute the audio inputs to power amplifiers feeding either fixed or portable monitor speakers. This application is ideal for church choir monitors or any performance area using stage monitors.

33.) SCHOOL CAFETERIA AND LGI ROOM RCX™ SYSTEM
This application demonstrates how to combine a school cafeteria and adjacent LGI (Large Group Instruction) room. An RDL RCX-J3S panel is installed in each room to provide both a microphone input (XLR) and a stereo unbalanced line level input (phono jacks). An RDL RCX-2S provides source selection and volume control in each zone. When the rooms are combined, all RCX-J3S audio inputs are active in both rooms and either of the RCX-2S control panels will control the audio in the combined room. Background music connected to the RCX-5C is selectable on each RCX-2S controller. If background music is not used, an RDL RCX-10RS controller may be substituted for the RCX-2S. The RCX-5C includes a paging input. RCX-5C line level audio outputs feed power amplifiers for each zone. The RCX-2S and RCX-J3S are high durability institutional stainless steel models. RDL RCX-3S and RDL RCX-3RS high security key operated controls are also available.

34.) SMALL CHURCH SOUND SYSTEM
This is a cost-effective sound system for a small church. There are three groups of microphones: platform, choir and sharing. The volume of each group is adjustable through user controls on the RDL RU-MX5 main house mixer. The RU-MX5 also provides volume control for the preacher’s wireless mic and for an auxiliary audio source, such as a CD or tape player. The RDL STD-600 sends the final audio output to two amplifiers, one for the sanctuary speakers and one for the fellowship hall. Depending on the desired level of user accessibility the RU-MX5 may be mounted in a wall, in the pulpit or in a small secured equipment rack.

35.) SourceFlex™ SYSTEM - FIVE ZONES
This application demonstrates how to distribute music and program sources to five different zones using RDL’s SourceFlex system. The stereo outputs from five separate audio sources are converted to balanced mono signals through five RDL TX-J2s feeding the RDL SAS-8i inputs. The input signals also feed the RDL SAS-82 through the interconnect cable. The SAS-8i and SAS-82 give the installer the provision to set the maximum listening level at each station. Each zone has a RDL SAS-RC8 allowing for both program source selection and level control.

36.) STEPPED LEVEL ADJUSTMENT FOR AMBIENT LEVEL CHANGES
The circuit shown is ideal in applications where paging signals into a power amplifier are normally OK, but at times a high ambient noise level makes the paging impossible to hear. This would be common in a factory setting where heavy machinery is in use at some times, making higher sound system levels necessary while the machinery is operating then again restoring the level to normal when the machinery is no longer operating.

37.) “OFF-AIR” IFB AUDIO DUCKING
This application utilizes a voice activated relay to trigger a ducking module which switches “off-air”audio and 2-way audio. In this example, the output of the ducking module is sent to a wireless IFB transmitter which transmits to a receiver that an announcer or other such talent can hear the “off-air” audio until the 2-way radio is keyed by the director. The “off-air” audio is then ducked and then the 2-way radio is sent through to the output.

38.) “Off-air” IFB Audio Ducking
This application utilizes a voice activated relay to trigger a ducking module which switches “off-air”audio and 2-way audio.