Modifying a closed box (classical)

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Edzard
Beefwood
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Joined: Sun Jun 19, 2011 7:33 pm
Location: Eindhoven - Holland

Re: Modifying a closed box (classical)

Post by Edzard » Fri Nov 06, 2015 9:48 am

Thanks Trevor! Some of the above pictures are with the setting as you described in your paper and I took a few with 20X.

Makes not that much difference.




Best regards,


Edzard

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Trevor Gore
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Re: Modifying a closed box (classical)

Post by Trevor Gore » Tue Nov 10, 2015 9:22 pm

Edzard, I still have a concern that there is something wrong with your plots, though I have not had any new ideas as to what. Increasing the sampling rate has the effect of reducing the spectral line resolution, so, in general, it's not the best things to do. The relationship between sampling rate, sample size and spectral line resolution is detailed in Appendix 1 in the black book. It also discusses the tap rate that you should use. As you have found, more than one tap per buffer produces a lot of "grass" on the plot.

I still have a suspicion that there may be something wrong with the signal level. For example, when I adjust the signal level in VA 9 running in Win7, nothing happens, because another program (in my case DTS Audio Control Panel, running on a HP laptop) takes charge of all the signal levels. So even if I take the signal level to zero in VA, I can still get a plot, same as before. For example, if you are using a USB mic, the software that came with the mic may be setting the signal level totally independently of VA. It may be worth checking.

It might also be worth trying the later versions of VA, which are likely better suited to running under Win10.

Good luck!

Edzard
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Posts: 23
Joined: Sun Jun 19, 2011 7:33 pm
Location: Eindhoven - Holland

Re: Modifying a closed box (classical)

Post by Edzard » Wed Nov 11, 2015 3:10 am

Trevor,

Thanks for your input. I will have an other look at VA/Windows/USB mics and come hopefully back with some better results.



Best regards,



Edzard

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