Microphone Selection Guide
The most common microphones used in induction loop systems are 'electret' lecturn, handheld, boundary and lavalier microphones as they have the highest tolerance of magnetic feedback. Best practice (though not always possible) is to place the microphone(s) as close as possible to the speaker.
Dynamic microphones should not be used as they contain moving coil magnets which can be affected by the magnetic field generated by the loop.
A method that is sometimes suggested for overhead placement is a ceiling-mounted boundary microphone. This should be used with caution as (a) microphone too far from the desired sound source, especially in the case of a high ceiling and (b) the ceiling in buildings of modern construction is often an extremely noisy location due to air handling noise, lighting fixtures and building vibration.
Phantom power is provided on all PDA amplifiers so electret microphones with batteries are not necessary.
Conference table application (centre of tabletop, counter, etc)
AMT tie/desk mic
APM plated mic
MH handheld mic + G121 stand
Lectern application (for pulpits, lectures, etc)
AML fixed gooseneck mic, long stem
AMLS fixed gooseneck mic, short stem
AMD movable gooseneck mic, long stem
AMDS movable gooseneck mic, short stem
Lavalier application (e.g. for the lapel of an after dinner speaker)
AMT tie/desk mic
AMR/LA (radio mic) – 4 selectable frequencies
Ceiling application (recessed in the ceiling above a table)
APM at distances of 3 metres
PRO45 at distances 12 metres
Desk Microphone with Push To Talk (PTT) application
AMD/P (as AMD with PTT)
AMH handheld mic AMP professional handheld mic (connection lead required – contact our sales desk for advice)
AMR/HA (radio mic) – 4 selectable frequencies
To avoid interference, microphone cables should be sited at least one metre away from loop cable.
If in doubt about which microphone to use, please contact our technical department for advice.