Ampetronic Ear Symbol
Home // MLD7 MultiLoop driver
Show product video

MLD7 MultiLoop driver

2 x 6.4ARMS for areas up to 840m2 

The MLD7 is part of the new benchmark range for professional audio induction loop systems. The elegant, sturdy units feature the most compact and most robust design on the market, requiring only a single 19” rack mount.

The MLD7 is capable of driving a wide variety of multiple loop configurations from multiple simple loops to phase shifted array systems for the most challenging requirements. With an Ampetronic MultiLoop™ Low Loss design, the MLD7 will drive an area up to 840m2, or can be used to drive two perimeter looped areas of up to 700m2 each.

Designed to provide optimum efficiency and ample current for Standard compliant field strength, coupled with unmatched voltage headroom to ensure crystal clear sound reproduction without clipping or distortion at practical loads. MLD units are built to our exacting standards and are backed by our 5 year warranty.

MultiLoop™ Applications

The flexibility of Ampetronic MLD units allows each output channel to drive separate loops, or two drive two overlaid loop patterns, with or without the selectable phase shift between the two channels.

Two separate simple area loops (or perimeter loops) can be driven at the same phase or with 90° phase shift. This can be used to cover large areas with no metal losses, or multiple different areas in the same facility.

Two loop layouts can be driven configured as multiple loop segments with or without phase shift. Simple array, low loss array or low spill array designs can create different performance to optimise field strength over any area, and minimise loop ‘spill’ for adjacent systems or for confidentiality.

Contact Ampetronic for free advice on all loop applications, design tools and support are available to check the expected performance for your application. Most commonly used design types are low loss and low spill:

MultiLoop Low Loss Systems are used to:

  • Compensate for high losses due to metal structures
  • Drive large areas where perimeter loops cause too much variation

MultiLoop Low Spill Systems are used to:

  • Perform the same tasks as a Low Loss systems, but also minimise ‘spill’
    – confines signal to within 1.5m of looped area, suitable for adjacent rooms e.g. cinemas, classrooms, or confidential applications.

Applications include

  • Conference facilities
  • Stadia & Sports Halls
  • Cinemas & Theatres
  • Courts & Confidentiality
  • Classrooms & Lecture Halls
  • Airports & Railway Stations


Product Code:

  • Features
  • Specifications
  • Standards
  • Downloads
    • Drives 2 output channels at 6.4ARMS each, featuring accurate and stable 90° phase shift
    • Up to 840m2 MultiLoop™ area coverage
    • Upto 2 x 700m2 Perimeter Loop area coverage
    • Space saving 1U rack mount unit, the most space efficient loop driver available
    • Front inlet & rear exhaust fan cooling for true rack mount integration
    • Rack mount or free standing installation
    • Can be used with or without phase shift to drive independent loops
    • Optimised to reproduce speech frequencies with unmatched intelligibility
    • Supreme musical reproduction
    • Automatic Gain Control
    • Metal loss correction
    • Active loop error monitoring & dual loop fault detection at start-up
    • Versatile input selection
      • 2 x XLR balanced mic / line switchable inputs
    • Low lifetime cost
      • Based on proven technology to ensure excellent reliability
      • 5 year warranty
    • Tested to, and compliant with: IEC 62489-1 induction loop amplifier performance standard
    • Free technical support
  • Maximum area coverage for MLD7 MultiLoop™ systems (m2)

    Loop DesignNo Metal Loss*Moderate Metal Loss**High Metal Loss***
    Low LossN/a300170
    Low Spill550190130
    Perimeter Loop @ 1:1 Aspect Ratio2 x 400max 5m loop widthn/a
    Perimeter Loop @ 3:1 Aspect Ratio2 x 650max 5m loop widthn/a


    Typical scenarios are based on *a building with no structural metal, **a building with reinforced concrete (re-bar) construction.


    Power160W 230V AC nominal, 45-65Hz [120V option available]
    Power switch & LED indicator (Hearing Loop logo) on front panel
    Input 1 & 2
    Programmable Microphone / Line
    XLR balanced input with programmable 15dB gain boost switchable between microphone and line on the rear panel.
    Microphone specification; 200 – 600Ω, sensitivity -55dBu.
    Selectable 12V phantom power on microphone only
    Line sensitivity; -30dBu
    Screwdriver adjustable front panel recessed gain control


    Loop Output Drive Voltage17VRMS(24Vpk) at maximum output current per channel
    Loop Output6.4ARMS (9Apk) continuous 1kHz sine wave peak >9A per channel
    Drive CurrentCont. pink noise 3.2ARMS short term peaks >13A per channel

    Front panel recessed controls

    Drive current indicated on two 6-LED displays in 3dB increments

    Loop ConnectorsNeutrik NL4 Speakons (supplied) for each output
    Loop MonitorProvides access to monitor actual loop current via a 3.5mm stereo headphone connector on front panel
    Channel A on left, channel B on right
    StatusA pair of isolated relay contacts to indicate system status;
    fault = open circuit: system OK. = short circuit
    DC OutputResettable, fuse protected 12V 0.1A.


    Idle1/6 peak Output Current (Speech)1/3 peak Output Current (Pink noise)Full Power
    DriverChannelsCurrent (ARMS)Load Resistance (Ohms)AC In (W)BTUAC In (W)BTUAC In (W)BTUAC In (W)BTU



    Frequency Response80Hz to 6.5kHz
    DistortionTHD+N <0.2% 1kHz sine at full current
    Automatic Gain ControlThe AGC is optimised for speech. Dynamic range >36dB
    Metal Loss CorrectionCorrects system frequency response due to metal structures in a building.
    Gain constant at 1kHz, adjustable gain slope from 0 to 3dB per octave.
    This does not compensate for signal loss from metal structures which can be significant.
    Phase ShiftUser selectable at 0° or 90° between outputs


    Fault MonitoringFault indicators on the front panel:

    Clipping – delivering over the rated voltage (per channel)

    Temp – unit is too hot (temporarily mutes output signal)

    Loop error – short circuit / open circuit error (per channel)

    Status ContactA pair of relay contacts are provided for remote fault monitoring
    CoolingTwin variable speed fan cooled. Front inlet, rear exhaust.


    SizeFull width 1U 19″ rack mount.
    Width 430mm Depth 250mm Height 44mm
    Mounting OptionsFreestanding
    1U 19″ rack mount (brackets included)
    EnvironmentIP20 rated; 20 to 90% relative humidity; 0 to 35ºC

    Equipment supplied as standard

    • Handbook and installation instructions
    • 197 x 252mm loop system present sign (deaf logo)
    • Region specific mains cable
    • Loop connector for each output
    • Rack mount brackets
    • Status Connector
    • DC Connector

    MLD7 optional accessories

    Ampetronic can supply a range of accessories to meet the specific needs of your installation:

    Installation Accessories

    • 18mm x 0.25mm copper tape
    • PVC extrusion to protect copper tape
    • Installation / warning tape to fix cable or tape to a floor

    Input adaptors

    By using the appropriate input adaptor or preamplifier the MLD7 will accept multiple additional inputs or audio inputs from other sources:

    Input TypeAdaptor
    100V line input
    Low impedance speaker line
    Line Level
    ATT-UX transformer isolated attenuators
    Unbalanced microphonesMAT1 adaptor
  • This product is designed to form part of a system that can meet all of the requirements of the international loop performance standard IEC60118-4, and the relevant parts of BS7594. To fully meet requirements of these standards, correct design, installation, commissioning and maintenance are required.

    All specification data has been compiled in accordance with IEC62489-1, the international standard for audio frequency induction loop equipment. Specification data should only be compared with data compliant to this standard.

    This product is CE market to all relevant safety and EMC standards, and is NRTL(ETL) approved for sale in North America.

    For detailed information on approvals, standards compliance and how to interpret the technical parameters on Ampetronic datasheets, please visit the support section of our website or contact support@ampetronic.com.

Related products

Explore all ampetronic products

Related Sectors

Explore all Sectors

Related case studies

BAA Conference 2014

BAA Conference 2014

Bournemouth International Centre

MLD Series

Cardiff City stadium

Cardiff City stadium

Cardiff, Wales


Cedar Centre – Anglican Community Church

Cedar Centre – Anglican Community Church

Birkdale, Australia

Low spill MultiLoop™

Dereham Memorial Hall

Dereham Memorial Hall

Norfolk, United Kingdom

Custom design

Freemasons hall

Freemasons hall

London, United Kingdom

Hammersmith Academy

Hammersmith Academy

London, United Kingdom

Large multi-functional space

Kultur & Kongresshaus Aarau

Kultur & Kongresshaus Aarau


Exceptionally high quality Ampetronic equipment

Melbourne airport

Melbourne airport


Now providing genuine benefit to travellers

Explore 109 case studies