AGC == Frequency Fitting ?

Stevie Blunder sungstad at nospam_pcisys.net
Mon Dec 31 06:56:11 EST 2001


AGC could be applied to the input, before
equalization, or the output after equalization, or
per band.  There are implications that determine the
choice. I would assume the ideal would be AGC per
band output. This would limit the level of each band
without affecting sensitivity to the other bands.
But this would tend to change the character of
sounds, an esthetic compromise. However, it's
probably better than having a lot of gain in one
band that activates a common AGC and mutes other
sounds.


xiaoxianbo <xiaoxianbo at 263.net> wrote in message
news:bad602a8.0112070026.793f784c at posting.google.com
...
> In some paper, authors introduced hearing aid
designed with 4
> frequency channels or 8 channels , plused
different weight
> coefficients, to fitting the person's audiogram. I
think the purpose
> is to keep the sound level in around the Most
comfortable level of the
> hearing impaired. And I think AGC(Automatic Gain
Control) does the
> same work, it prevent the sound to be too loud and
exceed the ULL, and
> make the sound at elevated threshold sounds the
same level as normal
> hearing person.
>
> Does frequency fitting and AGC the same work?
> If a hearing aid device have a good AGC(the
coefficients are
> time-varying and changes with different input
level and frequency), it
> needn'a a frequency fitting? Becauce AGC can make
the sound
> comfortable and audible.
>
> Who can explain the difference between AGC and
Frequency fitting to
> me?
> thanks.
>





More information about the Audiolog mailing list