loudness scaling of time varying chirp signal

[antz007]

Hi there

I have an audible chirp signal program on labview which produces an audible linear swept sine signal. This basically runs from my computer and through an audiometer where I can control the intensity of the signal. The problem is I have no idea of how to scale the signal so that it is equally loud along the entire sweep duration. Does any body have any ideas on how to create the sweep so that it is heard equally loud with reference to the fletcher munson curve? Or what steps need to be followed for this type of set up? It doesnt have to be perfect, but close enough.

Thanks so much
Anthony  

[johnsold]

Anthony,

I would consider digitizing the equal loudness contour curves. Use a table lookup to multiply the signal amplitude at each frequency.  The desired loudness would select a row from the table and the current frequency would select a column.

I did something similar to that in LV 1.2 to compensate for differences in amplifiers and speakers.

Lynn

[Diwaker]

Hi!

Can you please attach the same file but converted for Labview 8.5.1

Thank you!

[tinnitus]

hello,

here in 8.0

[tinnitus]

Hello,

to obtain such a thing you have to consider frequency response of your global sound generation :sound card, speakers  and to correct it also

regarding the human  ears

Regards

Tinnitus

[Diwaker]

Hi!

Thank you very much. But the copy that you attached yet seems to be the later version and my 8.5.1 does not open it. I am also looking for correction methods to compensate the power of chirp in second pass.

regards,

Diwaker

[tinnitus]

this should be the right one