TOPIC:

Hi

I start this topic just wanna know detail of the calibration data txt, how I could calibrate the UMIK using that file in user appliations ?

Best regards,
Power Pan

Applications often enable the loading of a calibration file.

One such application is Room EQ wizard (REW).
Follow this REW user guide link and read the ‘ Mic/Meter Calibration’ section and following section for more details.

thanks for replying.

I want to create something myself. still not enough information for to to use that data.

the link tells
" It should contain the actual gain (and optionally phase) response of the meter or microphone at the frequencies given, these will then be subtracted from subsequent measurements. "

but, what is the range, filter type ? sorry for the stupid question cause I'm a newbie...

Hi, I am also trying to figure out how to apply the calibration .txt files to my microphone response without using REW. I am using matlab to record responses using my UMIK-1 mic, FFT the response to analyze it in the frequency domain, where I would assume I need apply this cal file. Is there an equation for applying it or a description of what the data actually is so I can figure out how to apply it with an equation?

duchoraff wrote:

Hi, I am also trying to figure out how to apply the calibration .txt files to my microphone response without using REW. I am using matlab to record responses using my UMIK-1 mic, FFT the response to analyze it in the frequency domain, where I would assume I need apply this cal file. Is there an equation for applying it or a description of what the data actually is so I can figure out how to apply it with an equation.

Have you tried using REW? My bet is you'll find it does everything you need pretty well, without this complexity. And I'm saying this as someone who has used Matlab extensively in the past.

 

As long as it is just about gain correction, you can see in the file that it lists a frequency and a correction in dB. Hence, you can indeed take the fft of your signal in dbs, and subtract the correction from it. As your resolution might not match the resolution of the file, you can either create a histogram and bin the values in your fft or simply, e.g., use a linear interpolation between the values of your cal file and subtract this interpolated function. I would do this linear interpolation in the log domain, as this also matches the value distribution as far as I remember. 



 

The file is just a text file with 2 columns. The first column is the frequency in Hz and the second column is the mic's response in dB for that frequency. You can linearly interpolate between points.

Hi there,

I bought a UMIK-2 microphone. In the calibration file, at the beginning, there is some text as below:

"Sens Factor =-10.67dB, AGain =18dB, SERNO: 8103848"

What does Sens Factor and AGain mean and how should I combine them with the calibration file?

Thank you for your anwsers