Problem with Low Pass Filter

Hi guys,
i’ve a problem as stupid as strange…
i recorded 100 sounds using audacity.
If i use Multiple exportation to save the sounds, all works fine.

However if i use a Low Pass Filter (with 4KHz and 48dB), when i save the sounds, i obtain the 100 sounds with as silence as much is the total duracion of the project…
this is the original project with the sounds
this is the project with filter

thank you guys :confused: :exclamation:

I can’t download the second project because dropbox says it’s too large.

I suspect the problem is that you applied the Low Pass Filter to the entire project in one go rather than to one track at a time.
“Nyquist” effects (the Low pass Filter is a Nyquist effect) cause selected empty track space to be rendered as silence, so if you select the entire project and the start/end times of all tracks do not match, then the selected “white space” (empty space) will be converted to “flat line” silence, which will then be included in the export.

The solution is to process one track at a time so that you only select the actual audio and do not include leading / trailing silence.

If you are still stuck with this, please tell us what version of Audacity you are using (see the pink panel at the top of the page).

Please, make a zip file of the project and the data folder if uploading to Dropbox or other servers. This makes it far easier.