About Us

Induction Loop Systems

Loop Questionnaire

Induction Loop Receivers

Induction Loop Testing Equipment

Ambient Noise Compensation

Sound Field System Accessory

Multisensory Sound Lab

Airplane Assistive Listening System

Client List

Related Articles

Loop Systems & Accessories Pricing & Ordering

Contact Us

The Microloop II is a compact & transportable induction loop assistive listening system with a 90-foot loop wire suitable for use at home as well as in classrooms, meeting rooms and automobiles (with optional car kit).  It’s small size and light weight makes it the ideal portable small area loop system. (Click on photo to view enlarged image.)

Compatible with all telecoil-equipped hearing aids, cochlear implants and induction loop receivers,  the Microloop II induction loop assistive listening system comes with the following components:

• One loop amplifier
• One plug in clip-on omnidirectional microphone w/ 10 foot cord
• One 12 volt AC adapter
• One 90 foot loop wire on spool
• Ten self adhesive loop wire clips
• One carrying case with shoulder strap

Choice of VHF/UHF clip-on or hand held wireless microphone transmitter, wireless microphone receiver, AC adapters and patch cord.  Noise canceling head worn and collar microphones, and rechargeable battery options are available.

The Microloop II Dual FM comes with ALL of the above, plus:

Choice of second wireless microphone.

• Two microphone inputs (1/8” miniphone jacks), 1-100 millivolt sensitivity, 600 Ohm, phantom powered for the electret microphone(s) provided with system NOTE:  The omni-directional microphone furnished with the Microloop will function as a conference microphone by setting it flat on table surface, positioned 3-5 feet from speakers.
• One line level input (1/8” miniphone), .5-1 volt, 600-10K Ohms impedance
• One line level output (1/8” miniphone), .5-1 volts, 600-10K Ohms impedance
• One loop wire dual push terminal connector
• Amplifier output:  2 amps @ 1 kHz into 1 Ohm load
• Wireless microphone/s (Microloop II FM/Microloop II Dual FM):
• Choice of clip-on or hand held VHF/UHF band wireless microphone systems with 150 foot range, includes patch cord for interfacing with Microloop amplifier (rechargeable options are available)

Controls:

• One volume control adjusts all three inputs simultaneously
• One tone control acts as bass boost, maximum +10 dB @ 100 Hz

Microloop loop wire:
90 foot 22 gauge stranded single conductor on small spool.  A boosting of the signal strength can be achieved by increasing the number of turns of the loop wire. The 90 foot perimeter limit should not be exceeded and the maximum number of turns should not exceed four.

• The Microloop volume/tone controls, and the position of the listener & the pad, should be adjusted until the best sound is received.
• Two Loop Pads may be powered by one Microloop.
• Please follow the Microloop instructions for further information on setting up the system.

Frequency response:
Equalized response is in accordance with IEC 118-4 frequency response specification:
100 Hz – 5 kHz +/- 3 dB

Automatic gain control:
maintains consistent signal levels

Dimensions & weight:

• Amplifier:  8”W x 3 ¾”D x 2”H
• Carrying case: 9”W x 6”D x 6”H (Microloop II), 13½” W x 6”D x 6”H (Microloop II FM/Microloop II Dual FM)
• Microloop II weighs 3 pounds;  Microloop II FM weighs 4 pounds;  Microloop II Dual FM weighs 5 pounds 

• Using a telecoil/telephone switch equipped hearing aid or Induction Loop Receiver, a pre-installation listening check should be performed in the area where the loop system will be installed to ensure that there are no sources of strong electromagnetic fields that can interfere with the system.  With the hearing aid’s volume control set for normal conversational listening, switch the aid to “T”. The amount of buzz/hum should be minimal throughout the planned loop area.  If an Oval Window Induction Loop Receiver is available, hold the receiver in an upright position. The receiver's LED should not be illuminated by background noise. Please contact Oval Window Audio for more information concerning the measurement and mitigation of electrical noise.
• The loop wire may be installed in crawl spaces, under carpeting, in plastic conduit or clips on the wall, on/above ceiling, or simply taped down for temporary use.
• In order to maintain proper signal strength and signal uniformity, the loop perimeter should not exceed the 90 feet of wire supplied with the system.  If the full 90 feet of loop wire is needed to cover the area, lead-in wire may be used.  14 gauge (or heavier) wire is recommended in order to minimize power losses.
• Due to “dead spots” that occur directly above and below the loop wire, the sides of the installed loop wire should not be situated directly above or directly below seating within the listening area. 
• The loop wire must not be run in continuous contact with metal, either directly above or below the loop wire.  Loop wires may cross ceiling framework and may briefly run behind metal furniture.  At least 70% of the total loop must be free of metal obstructions.
• At least 70% of the loop wire should be installed in the horizontal plane.
• The loop wire must completely encompass the listening area. 
• The height of ceiling loop wires must not exceed 10 feet above the floor of the listening area. 
• Floor level loop wires must not exceed 3-4 feet below the floor.
• A loop system will transmit signals that spill outside the looped listening area.  At least twice the length of the longest side of the loop must be allowed between looped areas on the same floor. In regard to loop systems on different floor levels, the systems should be separated by at least one half the length of the longest side of the loop wire.
• Please contact us regarding special techniques that may be used to reduce signal spill over.
• In some listening environments, additional power is needed to overcome background electrical noise or to offset losses due to metal furniture and building materials.  To boost power, additional loop wire may be purchased and connected in series (end to end) with the existing wire in order to create a multi-turn loop.  Total looped area should not exceed 90 feet in perimeter.
• Avoid running loop wire in close proximity and parallel to telephone lines, microphone cords and video feeds.  Maintain a distance of at 12”.
• The Microloop II may be installed in vehicles. Click here for information on the Microloop Car Kit.
  
• The microphone supplied with the Microloop II is very sensitive and may be held or clipped on to the person speaking.  For small meetings, the mike may be placed flat on a table top, centered 3 to 5 feet from speakers. 
• An optional second microphone may be plugged directly into the Microloop II.  Y cords may be used to allow for additional microphones.  Only electret powered microphones available from Oval Window Audio should be used.
• External equipment such as radio, television and sound systems may be connected to the Microloop II.  A patch cord is required that matches the LINE OUTPUT jack of the external equipment to the Microloop II’s LINE IN 1/8” miniphone jack.

All Oval Window Audio products are sold on a 30-day satisfaction guaranteed basis and with a 3-year warranty covering parts and labor.  Exceptions to this warranty include microphones, rechargeable batteries and ear/headphones which are guaranteed for 90 days.  Warranty will be voided for equipment that has been abused, altered or operated in a manner contrary to directions contained in the user manual.  A return authorization must be obtained for all equipment returns and servicing.