What is a speech recognition microphone..
and what does this mean .. ? 

  Incorporating a speech recognition quality microphone means that
the system described uses a microphone with a "flat" frequency reponse
across the frequency range of the captured speech. It also means more than
a good microphone element - it means superior microphone housing design
that avoids echo, and other unwanted acoustic distortions that occur
when even a good microphone is located in a bad housing design.

 A 'good microphone' will always perform good noise canceling; very good
accuracy from the microphone for speech recognition typically requires
unwanted background noise to be eliminated, so not to be 'heard' by
the recognizer and interpreted as speech sounds.

There are typically three types of noise canceling;
1. Using a microphone element with a super cardioid pickup-pattern;
2. Using mechanical noise canceling in the microphone houseing design;
3. Electronic or 'active' noise canceling in the circuitry & housing.

 Of the above three noise-canceling mechanisms, either (1) or (2) is usually
better. Speech recognition software typically tests signal to noise ratio when
doing a microphone "setup" or when respective setup wizards are run;
Whenever a new profile is started, for example, with Microsoft Speech Recognizers
(which the LOBE is optimized for) the wizard will test & calibrate the recording
device settings for the audio input device. "Active" noise canceling has tended
to confuse these wizards or cause false warnings, telling the user the
microphone is poor when in fact it may be quite good.


What about the wireless aspect .. ?

It's important to note that even when wireless systems incorporate
a "speech recognition quality microphone" element, meeting specifications;
If the captured voice bandwidth, from that microphone element isn't
successfully transmitted to the base unit & then sent off to the recognizer,
Even though a microphone is present that meets necessary criteria,
the system isn't necessarily a wireless system that will render good
voice delivery for accurate speech recognition.

The LOBE's headset microphones meets speech recognition standards in two areas;
it provides power-consumption friendly noise-canceling via both mechanical
and a basic cardiod pattern pickup-field, and has a rather flat frequency
response plot across the entire spectrum of speech bandwidth it captures.

The LOBE's headsets' wireless protocol is especially designed for, and is the only unit
presently able to, enable multiple users to transmit an 8khz voice bandwidth
signal in one close environment, as well as being the only commercially-available
unit designed to transmit a digital quality 16khz/8khz voice bandwidth signal.
Everything the microphone captures from the user's voice is sent.


..why is frequency response important .. ? 

Here's why:
Frequencies from about 200hz to about 5khz include commonplace speech data,
and higher frequency responses are necessary for true intelligibility.
Upper frequencies have the most significance for speech information
(often called speech data)about the phonemes (Wikipedia definition) you are saying,
for example spoken fricative consonants (Wikipedia definition) like [s], [z] and [3] for instance.

The frequency plot below is an example of the fricative consonant "S"
that is pronounced in ending the spoken word "Yes".
Clearly; most of the energy from this particular speaker's fricative "S" sound
doesn't really become significant until about 5.5kHz., which is well past the
'toll quality' ranges offered by other digital headsets/wireless microphones.
(Hertz frequency integers are bottom row)


The overwhelming majority of speech engines, particularly Microsoft's
very advanced recognizers will utilize (if it's delivered) the sound frequencies from 50Hz to 16kHz (8kHz).
Here's Why:
This isolation of vital bandwidth (meaning: signal range - see below)
that Microsoft's speech recognizers require to accurately respond to what is said,
is distilled and constantly updated from decades of research on human speech.
[ E.G. Hearing aids now use a frequency response of 200Hz to 7kHz ]

Since speech recognizers can't "fill in what's not there".. they need to hear
at least the range humans must hear to achieve true intelligibility.

This image shows a simple spoken sentence: "The cat sat on the mat".

Frequency scale = 1:100

The important feature to note is the presence of peaks in
in the 6.5kHz range for a common word like "cat"..
and, again in the 5kHz range when "the mat" is spoken.


..And with VoIP, or telephony..
Is frequency response important? 

Keeping in mind the voice spectrum plots above;
When we talk to each other in a fairly quiet room
we hear everything we need for true intelligibility.
Since the physical characteristics of a sound wave are directly
related to the perception of that sound wave by the listener -

When you are sending/receiving what's needed to understand quite well;
You can be heard, and hear far more clearly.. more naturally, and far easier.
Your voice signal is then full-spectrum, crisp and actually sounds "Live".

What does 'bandwidth' mean .. ?

There isn't a universally precise definition of bandwidth (Wikipedia definition);
it is generally understood to be a measure of how wide a
function is in the frequency domain. When it is used here,
Bandwidth is a reference to voice frequency range.

You mentined fidelity, up above .. ?

"Fidelity" with voice transmit and/or receive devices means the reproduction
of speech sounds compared to the original speech signal.
High fidelity achieves extremely faithful reproduction - usually undetectable
when compared to the originating source's speech signal.
In the headset/microphone industry, 'fidelity' is usually interpreted as "audio quality".

To define voice fidelity by comparison; it's rather difficult to distinguish
the sounds "s" and "f" over a telephone, so telephones are low fidelity devices.

..the LOBE is High Fidelity?
and how good is that? 

Our headset system's extremely high fidelity is attributed to a) Frequency Response b) Design c)
component quality and d) optimization for Microsoft's speech recognizer .
Some details on this will be found on the Technical Data page.
Presently, when recordings from the LOBE's wireless scheme are compared to studio
recordings from 100 word dictations of words and figures, the difference is indistinguishable
to both the human ear and speech recognizers.
The systems itself is also optimized to contain very high Signal To Noise (Wikipedia)
ratio to augment the superior voice reproduction in the signal leaving the base unit.

 Whether for Speech Recognition, VoIP or PBX telephony of any kind
we are sure you'll find the LOBE the finest wireless headset system
available in today's marketplace.
Anywhere.

It's that easy.


We also provide aftermarket support for setup and training. 
Call us today at (877) 773-7797 for a free 10 day trial! 




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