There are various
types of microphones. There are desktop-based, monitor-mounted, computer-mounted,
hand-held and headset microphones. Speech recognition, while at your PC, works
best with a headset microphone. Here are some of the things to consider when deciding what
kind of microphone to use:
Noise Cancellation: Speech
recognition works best with a noise-canceling microphone. Most headset microphones provide
this capability to prevent sounds other than your voice from being heard. Noise-canceling
is not found in most hand-held, monitor-mounted and other desktop-based microphones.
Noise-canceling microphones are rarely distributed with a PC or sound card since they tend
to cost a little more than what manufacturers are willing to pay for.
Positioning: The position of the
microphone relative to your mouth is very important. Speech recognizers work best when
this position doesn't change. Headset microphones are always at about the same position
(just off of the corner of your mouth), while positions can vary significantly with other
|Type of Microphone
||You wear close-talk microphones on your head so that
the microphone is very close to the corner of your mouth. These work the best for speech
recognition because they have noise-cancellation. Unfortunately, the cord sometimes gets
in the way.
monitor or keyboard
||Microphones built-into computers, computer monitors or
keyboards do not work well for speech recognition because they are too far away and pick
up a lot of noise.
||Clip-on microphones clip onto your shirt, just below your
collar. They are not as good as close-talk microphones. Also, the cord sometimes gets in
||Desktop microphones usually rest in a microphone stand. If
you keep the microphone pointing towards you and about 6"(15cm) from your mouth, they
work well, but only in quiet rooms.
||You wear ear-piece microphones on your head so that the
microphone is as close to your mouth as possible. These work well for speech recognition
and dictation but not as well as close-talk microphones. Unfortunately, the cord sometimes
gets in the way.
||Although hand-held microphones pick up very little noise,
they are not convenient for most speech recognition purposes because they must be held
4" (10 cm) away from the user's mouth.
||These microphones look like normal telephone handsets, but
they plug into the microphone jack rather than the telephone jack. Handsets get good
|Resting on the computer
||Microphones that rest on the computer usually do not work
well for speech recognition because they are too far away and pick up a lot of noise.