In general, the Core Sound Omnidirectional MI microphones have a more
natural frequency response and are easier to position. We recommend
them first except when feedback or external noise is a problem -- then
we recommend the Core Sound Cardioid MI microphones.
If you need a bass roll-off or a slightly emphasized treble response,
we'd recommend the Core Sound Cardioid MI microphones.
If you prefer the Omnidirectional microphones but need to roll-off the
bass response, please contact us. We can provide a battery box with a
fixed bass roll-off filter at no additional cost.