Re : Re: Re : Re: Sound Generator Amplitude

[neil84]

Hi all,

I send et sine waveform to the speaker. If I change the frequency, the sound changes consequently however changin the amplitude dont changes the sound. how to do to change the sound amplitude. I need to process sounds with filters and amplifiers.

Thanks

[CoastalMaineBird]

You'll have to post code to see your exact problem, but amplitude is the height of the waveform.  If you're generating the sinewave, then use a different AMPLITUDE parameter.

[neil84]

I need to controlthe frequency and the dB sent to the speaker. when changing frequency on VI, the sound changes. when changing amplitude no changes accures about what I hear:

[Coq_Rouge]

---

neil84 wrote:

I need to controlthe frequency and the dB sent to the speaker. when changing frequency on VI, the sound changes. when changing amplitude no changes accures about what I hear:

---

You can not control the dB level the way you are trying to do it. Take a look here for an introduction regarding dB http://www.phys.unsw.edu.au/jw/dB.html.

Also then using the a DBL as type for sound output. The wave is normalized to +/- 1 in amplitude. I will recommend that you do not use Express VIs. Study instead the Labview examples for sound output and input

[neil84]

Hi,

I looked to the examples. there is some example where is possible to set volume. However there is no information about what sound level is sent.

My aim is to send a specific frequency and sound leve to the speaker ( W/m2).

Actually for  simulation 'm doing this:

to convert dB to Acoustic level and I need to send this specific level to the speaker

[Coq_Rouge · Accepted solution]

---

neil84 wrote:

Hi,

I looked to the examples. there is some example where is possible to set volume. However there is no information about what sound level is sent.

My aim is to send a specific frequency and sound leve to the speaker ( W/m2).

Actually for  simulation 'm doing this:

to convert dB to Acoustic level and I need to send this specific level to the speaker

---

Please trust me on this one. There are no standardized formats regarding sound card and amplifier systems/speaker system output level. So you can not take a random system and have it to output a some standard sound output level in W/m2. The only way you can do this, is to calibrate your system with some sound level measurement equipment

[neil84]

I found the way to process and amplify soud in labview: by multiplying in fourier space