Archive Session: Change Sample Rate...? [solved]

Getting Stuff Done How do I .... ?
#1

Hi guys!

I’ve done a live recording of a rock concert, using my Linux laptop with Ardour and the USB-Interface-mode of the Allen & Heath SQ-5 FOH desk. Worked like a charm, perfect and instant plug-and-play, really great! Laptop recorded four hours of about 25 tracks without any problems…

Only thing that I didn’t expect: The SQ-5 seems to be locked to 96 kHz. No choice here… (I would have gone with 48 kHz…)

So now I mixed the worthy parts… Everything fine, everyone happy… But I don’t wanna keep that amount of data archived…

  1. Is there a simple way to reduce the sample rate of all audio files to 44.1 or 48 kHz (for the archived session)?

Reading through the manual of Ardour’s archive functionality:

  1. Does “Notice also that converting to FLAC automatically normalizes the audio.” mean that the mix will be destroyed completely because all levels get changed drastically…??

Remembering my old days in Cubase: There was a great function to destructively delete unused parts of audio regions in order to save a lot of disk space (especially useful when archiving a finished project). My live recording at hand is a great example: I recorded three sets of the concert in one take each, each about 80 minutes long… If I only wanna keep a total of 30 minutes of one set, 50 minutes could be deleted permanently… Multiplied by 3 sets, times 25 tracks and 96 kHz - a lot of basically wasted disk space…

  1. Is there a simple way of stripping down audio regions to their exact length, thereby destructively deleting unused material before and/or after the part in use…?

Thanks for your advice!
Best regards
laex

#2

  1. there is no tool to resample an entire Ardour session. Years ago we had a standalone one, but it bitrotted due to lack of maintanance (it needs to be able to read Ardour sessions).

  2. Ardour does not offer destructive editing of audio files under any circumstances. No data is ever destroyed other than in the “Remove Last Capture” operation (when we actually delete the files entirely).

Sorry.

#3

Hi @paul ,

thanks for you immediate (!) answer! Fantastic! :pray:

→ OK, thanks. Next time I will resample the raw files and and create a new Ardour project before I start mixing…

→ Is that technically not possible (easily) or would you maybe consider a feature request like “strip down audio regions” for tidying up projects and saving heaps of (honestly, a great lot) of disk space?

.
And concerning the “FLAC normalization”: Does it destroy the mix?

#4

I found solutions!

Actually, it is quite simple to achieve it manually:

  1. Resample all recorded audio files (typically in the “interchange” folder…). I used SoX for that:
$ for file in *.wav; do sox "$file" "48k_$file" rate 48k; done
  1. Rename the wav-files so that the new files get the exact names the old files had.
  2. Open the Ardour-Project-File (.ardour) in a text editor and change the value of “sample-rate” in the second line to the new sample rate…

→ It seems to work perfectly fine this way, but as always, be careful and always have a backup before doing stuff like that.

#5

nope. When loading the FLAC file the normalization is undone.

#6

I suppose this could be achieved relatively easily using the bounce function (The Ardour Manual - Bouncing Regions)… But I don’t have enough time or need to explore it further right now… Just wanted to post it here for future reference…

#7

Thanks for the assuring clarification, @x42 !

All questions answered, thread marked as solved…
:pray: :pray: :pray: