How MFA Works

Speech limitations over the phone


We were born with the ability to hear up to 20,000Hz.  When talking on cell phones, that upper range is reduced to 3,400Hz.  There are still important speech information above 3,400Hz that’s why you often have to give context for high frequency sounds like “S for Sam” or “F for Frank” because without the context, the individual high frequency sounds can be imperceptible.


All languages have high frequency aspects to speech


While English only has a handful of high frequency consonants, other international languages like Chinese has fully 1/3 of their sounds being high frequency which means that over the phone many words can be misheard.


The MFA Solution


MFA precisely identifies all high frequency consonants within 1.5ms (the human ear needs 30ms to detect lag) and brings the audio information above 3,400Hz to within the narrowband spectrum so that previously unclear or inaudible words can now be heard with minimal distortion. Listen to the original sound “Gas” and the MFA processed sound “Gas” and notice that within the full spectrum context, there is almost no distortion.


Hear the Difference


Over the cell phone, the same sound now will have a marked difference. The original “Gas” sound with its high frequency information above 3,400Hz cut off by the phone lines, now has an “S” that is barely perceptible. However, the “Gas” sound processed with MFA, maintains the clarity of the “S” sound even over the limited bandwidth of the phone lines to give you wideband HD sound within a narrowband frequency range.