Use the onboard microphone to make frequency analysis: A good Idea?

[M.Lichtenheld]

Hello community,

I´m looking for an advice. I´m responsable for many LabView applications to control test rigs and collect data, mostly with NI Hardware.

Now the idea is to use the 3,5mm Audio In from the PCs that run the applications to record sound and than analyse this sound to get informations about our rotating test specimens. For example to detect damage to the bearing or higher friction.

This should be an addition to the whole application and is not vital to it.

I would put it in a seperate Software Modul.

In general, is this a good idea?

Has anybody tried this succesfully?

Do I risk problems with the Main Application?

Is it worth the effort?

Not native english speaker so please ask if something is unclear.

Thank you for any Input.

[Bob_Schor]

A microphone will pick up airborne sounds that it can "hear" (which depends on the microphone, its ambient environment, its frequency characteristics, etc.).  Given that you are talking about a mechanical vibration, an inexpensive accelerometer and some hardware to get the data into LabVIEW (a USB-6002 is pretty inexpensive) makes more sense, to me ...

Bob Schor

[Henrik_Volkers]

I like to use Speclab as a soundcard swiss army knife

also did some LV programming for the soundcard here

and a powerline frequency meter ... (somewhere here in the forum 😉 )

PCB made a accelerometer mit a USB connector that adds as a soundcard to your system.

Keep in mind that the soundcard timebase isn't that good.

While playing around with the soundcard of my old Dell Labtop, I found that the my line in and mic input was LP filtered at about 20kHz while the build in mic went up to 80 kHz  at 196kSPS@16bit 🙂

Launch it as a seperate application/vi  is a good idea. Keep in mind that extensiv waterfalls (spectrograms), while nice for visual analyses, can take a lot of memory and can eat one processor 😄

[M.Lichtenheld]

Thank you for your replies, helped me a lot!