Presonus Firebox & Final Cut Pro

[Russell Lasson]

Clicks typically happen when you try to use audio files with sample rates that are different from your sequence.

I’d guess that the files you’re bringing into FCP are 44.1k and your sequence is set to 48k. So it makes you render it and when you do, you hear clicks.

Check your settings. If you need to convert audio files at 44.1k to 48k, I’d suggest using iTunes. Just import them and then change your import settings in your preferences to be .AIFF at 48k (custom setting). Then right click on the files in iTunes and select convert selection to AIFF. Once it’s done, just drag the files out of iTunes.

-Russ

[Sylvain Sailler]

Unfortunately everything is set up in 48KHz 16 bits : footages, timeline, Firebox.
I have tried on to set up all in 24 bits (footages audio converted with QT pro), what seems to be native for the Firebox, but the problem is still the same.

I tried on also without any external drive, without any positive effect on the problem.

The last thing I did is to deactivate NAP with CHUD, which make a whine noise on my PowerBook. It stops the noise but don’t improve the Firebox sound with Final Cut.

[Russell Lasson]

So the files playback in FCP without rendering? I don’t know what else to suggest other than just keep trying things.

-Russ

[Sylvain Sailler]

Yes, the audio files playback without rendering.

But yesterday cuting some interviews I noticed that the clicks appears as soon as the sound level rises up. During these interviews, between two sentences, when there is silence, there is no clicks, but when the person begins to speak the sound begins to click too.

Yet the sound level as seen in the recording level gauge is not to loud (peaks at -10dB)…

[Russell Lasson]

I’m convinced that it is a audio sample rate conversion issue. I’m just not sure what to tell you on how to fix it.

Just for kicks, take the audio files into iTunes and use iTunes to convert them to 16-bit 48k AIFF files. Then bring them back into FCP and see if there are the same clicks. I know FCP is probably already telling you that they are 16-bit 48k audio files, but I have a hunch that this will fix it for you.

The only time I’ve ever heard clicks like you’re discribing is when the sample rate isn’t correct.

Let us know if it helps.

-Russ

[Sylvain Sailler]

Thank you very much for your help, Russ…
Here is the last test I did :

_I took a QT DV movie with strereo 48KHz 16bit sound, I exported the sound to a mono 48KHz 16bit .AIFF file I converted with iTunes to a mono 48KHz 16bit .WAV file.

_I created a new FCP project where I imported the 3 files (QT DV movie, .AIFF, .WAV)

_I can hear the 2 mono audio .AIFF and .WAV files in the Viewer without any click.

_But in the Timeline the same files produce some clicks. The Sequence audio settings are 48KHz, 16-bit, Default or Stereo Mix or Channel Grouped. The video settings are DV-PAL Quality 100%.

[I HAVE JUST SETTED UP MY SYSTEM LANGUAGE FROM FRENCH TO ENGLISH TO USE THE RIGHT TERMS IN THIS POST AND IT SEEMS TO ME THAT THE CLICKS HAVE NOW DECREASED A LOT!]

_But it remains some clicks !

_Reading the QT DV stereo audio movie in the Viewer or the Timeline / Canvas produces some clicks.

_It seems that reading the same file but with only one audio track produces less clicks than with 2 tracks.

_Anyway you can read all these files together in the same time with QuickTime Player without any click…

So for the moment I’ll use my system in English. Maybe one of these days I’ll understand the problem…

Do you thing it could be really a translation issue ?