A weighted Filter

[malkoba]

Hi

I require to obtain an A weighted frequency response from an audio signal. To do this I require to send the audio signal through an A weighted filter.  ( I have attached its' response curve). I have attached a programme in which a simulated sine wave is sent through a band pass filter ( 1st order butterworth filter with 700 and 20000 Hz cut off frequencies). But the filter response curve is not identical to that of an A weighted filter.

How can I modify this to make it identical to an A weighted filter.

Thanks

Mal

[AdamB]

Hi Malkoba,

The A Weighting is a representation of the frequency response of an average human auditory system Ear/Ear drums/cochlea etc and therefore is not recreatable using just a simple filter.

You need to either purchase the Sound and vibration toolkit for LabVIEW, or create an array of points that correspond to the curve, and apply those values to each of the frequencies that you read in (trust me this is not an easy way to go though)

Other than that there isn't much you can really do with just a filter as you have set up.

Post back if you need any more info

Thanx

AdamB

Message Edited by AdamB on 02-09-2006 07:52 AM