Faber Acoustical Forum

Faber Acoustical Products for Mac => Electroacoustics Toolbox => Topic started by: redbox on April 15, 2013, 12:50:21 PM

Title: Calibration Mic Trouble
Post by: redbox on April 15, 2013, 12:50:21 PM
Hi, I'm trying to calibrate my mic in Electroacoustics Toolbox but without success, probably I wrong to insert the values.

I have a Beyerdynamic MM1 omni microphone its sensitivity @1Khz is -36.9 dB re 1V/Pa, equivalent to 14.3 mV/Pa. When I insert this value in the I/O Device Setup -> Input -> Units = Pa and Sensitivity = 14.3 mV/Pa, the Sound Level Meter  indicates 115 dB, and believe me I'm in a quiet room  :-P, for example my Sound Level Meter on iPhone indicates 40 max 45 dB.

Where I wrong?
Title: Re: Calibration Mic Trouble
Post by: FaberAST on April 16, 2013, 08:43:17 PM
redbox,

Have you also calibrated the voltage sensitivity of the audio input device your mic is connected to? If that voltage sensitivity isn't correct, then the acoustical measurement won't be correct, either.

Ben
Title: Re: Calibration Mic Trouble
Post by: redbox on April 17, 2013, 03:32:13 PM
I have tried to calibrate my input device but without success. How can I know input and output sensitivity of my device?  :oops:

The Calibration Channel viewed in the Device IO setup, correspond to the physical loop between the input and output channel with a TRS cable?

I'm really sorry but I haven't familiarity with this stuff, I really need an explanation for dummies, please help me  :|  :cry: :|  :cry:
Title: Re: Calibration Mic Trouble
Post by: FaberAST on April 18, 2013, 09:58:11 AM
redbox,

I'm sorry you're having a tough time.

Have you read the calibration tutorials in the Help files (you can access them from the Help menu in the app)? There are tutorials for input and output voltage calibration, as well as microphone calibration.

Ben