I'd like to know if the (band) filters are designed conform IEC 61260.

[Michiel]

Hi, I'm desiging a softwaretool in Visual basic to analyse static wave data as a Real Time Anaylser does in real time. So this data has to be filtered in third-octave bands, conform to the hardware-version Analyser: The Nortronic 830.
Important is that the filters I need are exactly the same as the Nortronic is using, therefore I need to know if Norm standards (pref. IEC61260 or IEC225) were used when the filters were designed. If not, is it maby possible for me to adjust the filters conform to this Norm?

[JuanCarlos]

Hi,

Measurement Studio does not have any built in filter to perform octave analysis; we only offer standard compliant octave analysis in LabVIEW's sound and vibration toolset.

to create filters to conform to the standard probably the best way to go would be to obtain the characteristics of the filter required to comply and implement them with the CWDSP.IIRFilter function.

The parameters that you need would be the order of the filter, minimum sampling rate and the filter's coefficients. Then you can use CWDSP to perform the math for you.

I hope this helps you get started, let mw know if you have further questions on this.

Regards,

Juan Carlos
N.I.

[richardscheff]

Follow up question 20 years later.  I am looking at octave band filter vi located within soundvib_octave_llb.  It appears like it is producing a 9th order Butterworth coefficients. I say that because it is generating 8 reverse and 10 forward coefficients. 

It is a control variable for order and it can be set to 4.  But it seems no matter what integer value is used the resultant calculation is unaffected.

I need to verify the filter method.  Does anybody know the exact filter being used for sound vib octave sound power?