Why Does Icom Require a Specific Kind of Microphone?
Each brand of radio equipment has its own unique characteristics, and the well-respected Icom brand is no exception. Throughout its base-station design history, Icom has designed around using “condenser” or “electret condenser” microphones.
What Are the Differences Between The Types of Microphones (Dynamic, Electret, and Condenser):
Condenser and Electret Condenser microphones are powered microphones (as opposed to “passive,” non-powered Dynamic microphones). Condenser microphones require phantom power, and electret condenser microphones require bias power to operate. Icom radio microphone amplifier circuits are designed to power and be used with electret condenser microphones.
Dynamic microphones, on the other hand, bring many characteristics that can produce great audio, including high dynamic range and voice pattern control. But, being passive devices, they require gain. Icom radio microphone amplifier circuits are not capable of providing enough gain to properly drive dynamic microphones.
What do we do about this situation?
First, we set the gain characteristics of the microphone element to land right in the middle of where the Icom radios “want” the gain to be. This prevents overdrive while leaving plenty of headroom, so you never lack drive, even when making treble, bass, or other equalization adjustments in your transceiver.
Radio operators require their microphones to let their voice rise out of a silent background and reproduce their voice characteristics with the lowest possible distortion. Along the way, the frequency response may need to be adjusted for special or temporary needs (e.g., a bright, attention-getting sound for crowded band conditions or perhaps a more mellow sound for an evening local chat). And Icom transceivers have an array of adjustments on board to facilitate the shaping of your voice reproduction that goes out over the air. But without a sufficiently-broad adjustment range for the controls, you won’t get the full benefits of any microphone. This is where the iCM microphone comes to the forefront.
The iCM microphone features a carefully-engineered, quick-articulation-pickup iCM microphone element that detects every bit of scintillation in your speech in the time domain instead of the frequency domain. This allows the consonant sounds in your speaking to be picked up without having to over-adjust the treble range to bring those sounds out (the latter technique can lead to a “raspy” or “harsh” sound).
Finally, the hardware has been mounted in a carefully-engineered acoustic enclosure that provides high rear rejection of noise. Amplifier fans, other radios, and ambient room noises work against letting the world hear your voice–and we’ve engineered around these issues to give your voice a clear path to the world.
Bonus! The cable is included.
The iCM includes a pre-wired 8-pin microphone connector compatible with all Icom base station rigs using similar connectors. The gain characteristics are similarly ideal across the Icom base station product line, no matter the vintage. The iCM can also be used with modular microphone inputs with the correct adapter cable. Please see the Heil Ham Radio Compatibility Guide to find the right adapter cable for your radio.
The iCM: just plug it in, and sound great.