IR-CSV Infrared Wireless Classroom System

Advantages of Infrared

Infrared wireless microphone systems are the best solution for classrooms. In today’s RF saturated world a regular (VHF or UHF) microphone system risks interference from a variety of other devices and sources. Cell phones, radios, TV, PA systems, police and emergency service systems, etc., can all interfere with VHF and UHF, but not with IR. Furthermore, infrared is perfect for classroom audio, since, unlike the other systems, IR is short-range, cannot penetrate walls, and is dependent on line-of-sight. This means that a school can have as many classrooms as desired with individual audio systems without fear of interference. Since the Azden system is dual-channel, the teacher can have one microphone and a second person can also have a microphone. In addition, since each classroom system is on the same pair of channels, teachers can go from room to room without having to switch microphones.

Complete Classroom System

Although you can purchase components separately to customize your own system, Azden offers a convenient IR-CSV kit which includes everything you need to set up a classroom audio system: an IR receiver with ample power for 4 ceiling speakers (IRR-40P includes BC-30 power adapter), a teacher’s pendant IR microphone/transmitter (IRN-20), a student’s pass-around handheld IR microphone/transmitter (IRN-30) an external ceiling-mounted sensor (IRD-60), and 4 high-quality in-ceiling speakers (ACS-6.5), plus 2 AA-size rechargeable batteries (1HR-3U) and 2 power chargers (BC-31) for the transmitters. All you need to complete the installation is the wiring for the speakers and sensor. 

Components

IRR-40P

2-Channel IR Receiver

The heart of the Azden infrared system is the IRR-40P powered, dual channel receiver. It allows you to use and control the volume of 2 wireless microphones simultaneously, either for “team-teaching” or to use the handheld microphone for students to pass around. The receiver also has 2 stereo auxiliary inputs so that other line-level devices (CD player, MP3 players, VCRs, etc.) can be connected and played through the system. The teacher can also send the audio to a recorder or video camera, using the line-level output jack. For bigger rooms or odd-shaped rooms, up to 3 additional sensors can be attached. With all 4 of the ceiling speakers attached to the IRR-40P, sound is spread equally throughout the room, allowing all students to hear equally well.

IRN-20

Teacher's Pendant IR Microphone/Transmitter

A lightweight, chest worn, microphone/transmitter, the IRN-20 comes with an adjustable lanyard. It is both a microphone and infrared transmitter which wirelessly “links” the teacher to the IR receiver. It has a specially designed internal microphone array which provides great sound pick-up, but for added flexibility, mini-plug connections are included for an external microphone or line-level signal. The teacher can control the volume of the whole system with the volume control buttons on top. With just one “AA” battery (alkaline or rechargeable) the microphone can be used the entire school day without recharging or changing batteries. If using the provided NiMH AA rechargeable battery, it can be charged while installed inside the IRN-20, by connecting the BC-31 wall-charger (note that other battery brands will not be able to charge in-unit).

IRN-30

Mini Handheld IR Microphone/Transmitter

Small and lightweight, the IRN-30 is the perfect handheld “pass-around” microphone for student participation. The built-in microphone provides excellent sound pick up, but for added flexibility, mini-plug connections are included for an external microphone or line-level signal. It is powered by just one “AA” battery (alkaline or rechargeable) and is compatible with all Azden infrared models. If using the provided NiMH AA rechargeable battery, it can be charged while installed inside the IRN-30, by connecting the BC-31 wall-charger (note that other battery brands will not be able to charge in-unit).

IRD-60

External IR Dome Sensor

Designed to be mounted in drop-ceilings, a single well-positioned IRD-60 external IR sensor provides complete classroom coverage in most classroom situations. However, up to 3 sensors can be connected to extend coverage in larger rooms. Mounting is easy, and the sensor is connected to the IR receiver with a standard coaxial wire.

ACS-6.5

In-Ceiling Speakers (4 Included)

The ceiling speaker is designed to provide optimum performance for the teacher’s voice in addition to audio from other sources (CD/MP3 player, VCR, etc.). Each speaker features a sealed-back enclosure and 6.5” polypropylene midrange/woofer to produce natural bass response, while the coaxially-mounted 1” polycarbonate tweeter provides superior high frequency response. Easily flush-mounted in any drop-ceiling, four of these speakers provide smooth, evenly distributed sound throughout the classroom. All students can enjoy enhanced audio equally.

In addition to the components listed above, the IR-CSV kit comes with an AC power supply for the IRR-40P receiver (Part# BC-30), two wall-chargers for the transmitters (Part# BC-31), and two AA size Ni-MH rechargeable batteries (Part# 1HR-3u). Speaker wire and coaxial cable is not included with this kit.

Image Gallery

Specifications

IRR-40P 2-channel receiver w/ power amplifier

Sub-carrier frequencies: 2.06MHz & 2.56MHz
Type: Superheterodyne – crystal controlled
Modulation: FM
Pilot Tone Signal: 32.768kHz
Frequency Response Deviation: 50-10kHz ±3dB / less than 1%
Audio Output: RCA Jack Mono x2
Speaker Out: 5W x4 @4 Ohms
Line Input: RCA Jack (L & R)
Sensor Input: F-connector x3
Power requirement: 15V DC @ 2.7A (use model BC-30)
Size: 8.03″ W x 9.19″ D x 1.73″ H (204 x 233 x 44mm)
Weight: 3.3lb (1.5kg)

IRH-15c 2-channel handheld transmitter

Sub-carrier frequencies:  2.06MHz & 2.56MHz switchable
Modulation:  FM
Microphone element type:  Uni-directional dynamic
Frequency Response:  50-8kHz ±3dB
Battery Type:  2 – “AA” alkaline (1.5V) or rechargeable NiMH (1.2V)
Battery Life:  > 6 hours / alkaline batteries
Size:  9.65” x ~ 1.375” (245 x ~ 35mm)
Weight:  9.1oz (258g) w/ alkaline batteries)

IRN-20 Teacher’s Mic/TX

Sub-carrier frequencies:  2.06MHz
Modulation:  FM
Microphone element:  Uni directional ECM x2
Frequency max deviation:  <±40kHz
Frequency response:  100 – 8kHz ±3dB
Aux/Line input:  φ3.5mm mini jack
Mic input:  φ3.5mm mini jack
Mic gain adjustment:  from +6dB to -10dB
Battery type:  1 AA alkaline / 1 AA rechargeable NiMH
Battery life:  >8 hours w/alkaline battery
Size:  95 x 25 x 50 mm
Weight:  74g w/battery

IRN-30 Student’s Mic/TX

Sub-carrier frequencies:  2.56MHz
Modulation:  FM
Microphone element:  Uni directional ECM x1
Frequency max deviation:  <±40kHz
Frequency response:  100 – 8kHz ±3dB
Aux/Line input:  φ3.5mm mini jack
Mic input:  φ3.5mm mini jack
Mic gain adjustment:  from +6dB to -10dB
Battery type:  1 AA alkaline / 1 AA rechargeable NiMH
Battery life:  >8 hours w/alkaline battery
Size:  27 x 27 x 90 mm
Weight:  74g w/battery