ETF and Radio Shack SPL Correction (1 Viewer)

[Jon M]

I was wondering if anyone has a .cal file for ETF that corrects the response of the Radio Shack Analog SPL Meter. There is one on the ETF site, however, it does not make corrections in the low frequency ranges. I tried to take the correction values that are on the web and make my own file, however the program did not seem to accept them, I got the same results before and after entering the .cal file.

Thanks,

Jon

 

[BruceD]

Jon,

I built a calibrated mic and mic preamp for my ETF setup and this is the format of the mic calibration file I used.

Note that it has three (3) values:

frequency. . . .SPL adjustment. . . .phase adjustment

so here is an example of the beginning of my text file:

----------------------------------------------------

Nealmic 1-2001

204.204 0.312 2.36

212.256 0.307 0.09

.....

-----------------------------------------------------

As you can see the file name is followed by a blank line (important) and then data is represented as a set of triples (frequency, SPL, phase), each separated by a space, for each text line. Also remember negative values require a minus sign (-).

If you don't have the phase numbers for the RS meter's response, just put a zero (0.0) where the phase number should go. I think you need a number there to hold it's place

BruceD