how to implement a psophometric filter in Labview software

[Jake8]

I am trying to implement a psophometric filter in software for a noise measurment on a telephony system.

[Randy_H]

Jake8,

I spent some time searching not only ni.com, but many other Web sites as well. I could not find any algorithms to implement. If you have an algorithm, then I may be able to be some help. Are there any other weighted filter you could use instead? Please post again if you have an algorithm.

Randy Hoskin
Applications Engineer
National Instruments
http://www.ni.com/ask

[Tims]

Hi Jake8,

I don't know about your situation, but my use for a psophometric filter
was to filter the audio before a sinad measurement. I didn't find a filter
algothym in the time domain, but I did find the filter shape in the
frequency domain. My SINAD meter calculates the SINAD from FFT data, so
the all i had to do was apply the filter shape over the FFT data, and so
filtering it, then calculate the SINAD.

It is possible to synthesise a FIR filter from frequency domain data, but
I couldn't make it work. The problem with FIR's, is they do take a lot of
processing compaired to IIR's for the same frequency responce.
If their is an engineer out there that can synthesise a suitable FIR or
IIR filter, I can forward the articles that have the freq responce.


Tim

Jake8 wrote:

> I am trying to implement a psophometric filter in software for a noise
> measurment on a telephony system.

[Joe_H1]

I can build a psophometric shaped linear phase FIR filter at any desired sample rate. Give me some means to contact you for more information.