Listen Technologies ILD122 – Induction Loop Driver

Product Overview

The Listen Technologies ILD122 is a professional rack mountable induction loop driver covering areas above 200m², supplied in the US 110V configuration with a US cordset. It delivers 3.5Arms continuous into loops from 0.2 to 1.8Ω, with AGC optimised for speech and adjustable metal loss correction. Three mounting options — freestanding, 1U rack or wall — make it practical in rooms where rack space is not available. It suits mid-size auditoriums, houses of worship and multi-purpose rooms.

Product Description

Perimeter loop drivers are selected on loop area, aspect ratio and the metal loss measured during survey, not on room capacity. Two rooms of identical floor area can require different current ratings if one has a steel deck and the other does not.

The ILD122 covers up to 120m² at a 1:1 aspect ratio, 150m² at 2:1 and 200m² at 3:1, which is why the shape of the loop matters as much as the floor area when sizing a driver. Drive current is 3.5Arms continuous at 1kHz with short term peaks above 7Apk, into loop resistances from 0.2 to 1.8Ω. Frequency response covers 80Hz to 6.5kHz with THD+N below 0.2% at full current. AGC is optimised for speech with more than 36dB of range, and metal loss correction adjusts the gain slope from 0 to 3dB per octave to compensate for steel in the structure. Inputs are an XLR balanced microphone input for 200-600Ω microphones with 15dB user selectable gain boost, plus a 6.4mm balanced line jack. The chassis is 215 x 220 x 44mm at 1.8kg.

Loop conductor and terminations are ordered separately: 14 AWG hearing loop cable for perimeter runs, foil-to-cable crimp lugs where copper foil tape meets cable, and PVC protective extrusion where the loop is surface run.

Commissioning is a measurement exercise against IEC 60118-4, not a listening check. Pair with a field strength meter and its signal connection cables, and use a metal loss test driver at survey stage where the structure contains significant steel.

Key Features

• Over 200m² coverage — Covers 120m² at 1:1, 150m² at 2:1 and 200m² at 3:1 aspect ratio.
• 3.5Arms continuous output — Drives loops from 0.2 to 1.8Ω with short term peaks above 7Apk.
• Speech optimised AGC — Holds output consistent across more than 36dB of input range.
• Adjustable metal loss correction — Compensates for structural steel with 0 to 3dB per octave gain slope.
• XLR microphone and jack line inputs — Accepts 200-600Ω microphones with 15dB gain boost, or a balanced line feed.
• Three mounting options — Installs freestanding, in a 1U 19-inch rack, or wall mounted.
• Low distortion — THD+N below 0.2% at 1kHz at full current output.

Typical Applications

• Auditorium
• House of worship
• Conference room
• Boardroom
• Government space
• Training room
• Multi-purpose room
• Commercial meeting space

Technical Specifications

Specifications sourced from the Ampetronic ILD122 datasheet (UP32501-13). This part number is the US 110V configuration.

Frequently Asked Questions

How do I size the driver for my room?
By loop area, aspect ratio and measured metal loss, not by room capacity. A long narrow room covers more area for the same current than a square one, which is why coverage is quoted at 1:1, 2:1 and 3:1 aspect ratios.

What audio sources can feed it?
An XLR balanced microphone input for 200-600Ω microphones with 15dB user selectable gain boost, plus a 6.4mm balanced line jack for a mixer or DSP feed.

How is metal in the structure handled?
Metal loss correction adjusts the gain slope to compensate for absorption by steel in the floor or ceiling. The loss should be measured at survey with a metal loss test driver rather than estimated.

How is the installation certified?
By measuring field strength, background noise and frequency response against IEC 60118-4 with a field strength meter. A listening check does not demonstrate compliance.

Where is the unit mounted?
Freestanding, in a 1U 19-inch rack, or wall mounted. That flexibility suits retrofit work where rack space was not allowed for.

What loop cable should I use?
14 AWG hearing loop cable is the common choice for perimeter runs. Copper foil tape is used where a flat profile is needed under floor coverings, joined to cable with crimp lugs.

What warranty and support apply?
Warranty duration and technical support terms are set by Listen Technologies. Contact Creation Networks for current terms, RMA handling and pre-sales hearing loop design support.