dBA Messung mit Soundkarte/ dBA measuring with a sound card

[Coq_Rouge]

The example from MarianMO was somewhat confusing for your need. Even if it is step in the correct direction. Take a look at my half done mod of your program. You have to add the scaling functions. Also reading the sound buffer once every second should be more than good enough. Read this also http://zone.ni.com/devzone/cda/tut/p/id/4278

By the way running a Labview program with the continuous run button is a NO CAN'T DO. This function is for debugging only. Use a while loop like I did

I think this should work but I have not testet it;)

[Marian_O]

Bonjour Coq Rouge,

thanks for your clarification, but I am a bit confused about the constant at the while-loop:

Message Edited by MarianMO on 11-03-2009 01:52 PM

[Coq_Rouge]

My example was just meant as a push in the correct direction, or a casting frame for further programming. I am sure the honourable Alesis will be able to work on the minor details;)

Message Edited by Coq Rouge on 11-03-2009 02:00 PM

[Alesis]

First: Thank you very much to both of you!!!

I've looked at the example. But unfortunately it was not working.

However, I must first look what happens everything in vi.

I hope I will still get out somehow so I can finish the project 

(the dB(A) measuring is the last part from the whole vi!!!)

Best regards

Alesis

[Marian_O]

By the way: National Instruments Germany offers special student discounts for their training courses, if you are interested, take a look to:

http://digital.ni.com/worldwide/germany.nsf/web/all/12FEA617410A39418625745600480CA7?OpenDocument&no...

[Coq_Rouge]

My example had a few faults. Then you use the "SI Read.vi" the number of samples is equal to buffer/2. I did not know that. The rest is up to you.

[Alesis]

Tank you MarianMO!!!

That's great...

But my time is running!

This is my diploma thesis and my first project with LabVIEW. I must therefore deal with labview and acoustic.

Since both new to me, i simply have difficulties!

But as I said: I hope i can solve this dB(A)-problem and come to an end

Maybe with your help... 

Best regards

Alesis

--> thank you Coq Rouge for the new vi!!! I take a look at the vi and then report back!!!

Message Edited by Alesis on 11-03-2009 08:19 AM

[Alesis]

Hello again,

I get the dBA value, if I add up the rated spectrum over the frequency  and that is in ever-smaller increments over an integration ...

Can somebody help me to realize that in my vi?! 

Sorry but my LabVIEW knowledge is not enough, unfortunately!

Maybe if i see an example, all is clear. But without your help i think i can't realize it...

Thank you all

Alesis

LabVIEW Vers. 8.6

[Coq_Rouge]

I looked at your(my) VI ;). I will recommend that you do not use any window function. Also if you want things correct you must use the magnitude(peak) option. I do not quite understand what your trouble are now. Can you give a better explanation.  

[Coq_Rouge]

Also i did not see this one because I do not use Express VIs. But it is good example of a typical express VI trap. Bottom line do not use them. They actually makes a beginner struggle more. Well anyway, you must use the Build Waveform (Analog Waveform) Function. Owning Palette: Analog Waveform VIs and Function. So you get the correct dt into the FFT Express VI. Why did you change the setting that was working correct whit standard VIs?

Also a tip. Then you are programming you MUST keep attention to details. You can not just toss in some functions and hope every thing is correct. Every time you use a filter or spectrum function you must provide some information about the sample rate or dt(1/Fs)