Amplification is not about volume, it’s about clarity

SoundFields products - Induction loops

View details on our induction loops products below or download the Specification Sheets.

Specifications

LA-75 / LA-300 / LA-600 - 2/3 Channel Loop Amplifiers

Download the LA-75 Channel Loop Amplifiers brochure

Download the LA-300 Channel Loop Amplifiers brochure

Download the LA-600 Channel Loop Amplifiers brochure

Induction loop amplifiers

It is estimated that approximately two million people in the UK have hearing aids that are capable of receiving audio frequency induction loop transmissions.

Inductive loop amplifiers are a must for modern PA installations to give equal access to information and announcements to people with hearing disabilities. The Disability and Discrimination Act (1995) states that it is unlawful for service providers to discriminate against disabled people by providing them with a lower standard of service, or service on worse terms for reasons relating to their disability.

Soundfields's induction loop mixer amplifiers are designed to complement the LinkX IR series voice amplification systems.

The amplifers are available in three versions:

  • LA-75 2 CHANNEL LOOP AMPLIFIER - designed to cover 75m²
  • LA-300 3 CHANNEL LOOP AMPLIFIER - designed to cover 300m²
  • LA-600 3 CHANNEL LOOP AMPLIFIER - designed to cover 600m²

Each amplifiers features 3 inputs accepting input via XLR, 6.3mm Jack or RCA Phono with inputs switchable between mic and line with optional phantom power switchable on the rear panel. Tamper proof input level, bass & treble and loop current controls (recessed and adjusted by screwdriver) ensure that you can set up the system to suit the venue and there is even a built-in alarm circuit for evacuation alerts.

How it works

Induction loop amplifiers allow audio signals to be transmitted using a magnetic field to a suitably equipped listener. A magnetic field is created when current flows though a wire - in induction loop systems the wire is normally installed as a loop around the perimeter of the area. A small coil within a hearing aid or other suitable receiver then receives this magnetic field and converts it to audio at a suitable level for the listener.

The loop itself is simply an insulated wire installed at a low level, around the skirting board for example.

Hearing aids designed to receive induction loop signals generally have a switch marked 'M' for microphone and 'T' for telephone (Sometimes a combined position is provided). In the 'T' position a pickup coil, originally designed for picking signals from a telephone earpiece, is used to receive audio from induction loop systems.

The ideal signal strength for an induction loop system is such that a person switching between 'M' and 'T' would not notice a difference between the sound of someone speaking normally and a signal transmitted from the loop. To help in determining the perfect level it is often a good idea to engage the services of a hearing aid user - after all they are the ones that the system will most benefit. We also have available a simple inductive loop receiver that allows you to listen to the loop signal using an ordinary pair of headphones.

Loop output cable selection

It is important for the cable used to form the loop is capable of carrying the current that the amplifier produces. The table below is a guide to the maximum loop length for each cable thickness.

Cable Thickness 1.0mm² 1.5mm² 2.5mm² 4.0mm²
Total loop length < 60m < 110m < 200m > 200m

Specifications & features

LA-75 2 Channel Loop Amplifier, 75m²
Specification Value
Power supply 230Vac, 50Hz
Frequency response 50Hz - 5kHz
Input sensitivity : Line -6dBu, 8k ohms
Input sensitivity : Mic -56dBu, 2k ohms
Signal to noise ratio 75dB
THD <1%
Dimensions 264 x 242 x 88mm
Weight 4.06kg
  • 2 Microphone or line inputs
  • Input and output connection via PCB mount screw terminals
  • Tamper proof channel volume, bass, treble and loop current level controls
  • Built-in siren for evacuation alert
  • Peak current and siren LED indication
  • Vox priority
  • Mounting brackets supplied
  • Metal loss correction
  • AGC (automatic gain control)
LA-300 3 Channel Loop Amplifier, 300m²
Specification Value
Power supply 230Vac, 50Hz
(100W)
Frequency response 50Hz - 5kHz±3dB
Input sensitivity : Line -6dBu/6k Ohms
Input sensitivity : Mic -56dBu/2k Ohms
Signal to noise ratio 75dB (line),
60dB (mic)
THD <1%
Dimensions 425 x 266 x 44mm (1U)
Weight 4.7kg
  • Each channel accepts input via XLR, 6.3mm Jack or RCA phono
  • Inputs switchable between mic and line with optional phantom power +36Vdc
  • Built-in siren for evacuation alert
  • Tamper proof channel volume, bass & treble and loop current level controls
  • Peak current LED indication
  • AGC (automatic gain control)
  • 19" Rack Mountable
LA-600 3 Channel Loop Amplifier, 600m²
Specification Value
Power supply 230Vac, 50Hz
(150W)
Frequency response 50Hz - 5kHz±3dB
Input sensitivity : Line -6dBu/6k Ohms
Input sensitivity : Mic -56dBu/2k Ohms
Signal to noise ratio 75dB (line mode),
60dB (mic mode
THD <1%
Dimensions 430 x 280 x 88mm (2U)
Weight 7.2kg
  • Each channel accepts input via XLR, 6.3mm Jack or RCA phono
  • Inputs switchable between mic and line with optional phantom power +40Vdc
  • Built-in siren for evacuation alert
  • Tamper proof channel volume, bass & treble and loop current level controls
  • Peak current LED indication
  • AGC (automatic gain control)
  • 19" Rack mountable


 

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Registered Address: 35 Westgate. Huddersfield, West Yorkshire, HD1 1PA
Company Registration Number: 04760603