Thursday, April 09, 2020

audio processing - normalize to RMS with Reaper

Necessity is the mother of invention. Being unable to access my old laptop with the tools I needed to process audio files using my old method with Sound Forge, looked around for ways to do it on Reaper.

 Found some very good ways to do it using SWS Normalize filters if you are on Mac or Windows.

And for Linux, using just the built-in filters, found this excellent video which explains how to do it manually using a compressor and a limiter, and watching the master level meter - Setting the LUFS level in Reaper.

In my case, I created some template projects with the following, (on Reaper v6.05):

  1. View -> Floating Mixer Master. Right-click on the Mixer Master VU Meter, change the settings to Peak+RMS, and increase the window size to 5000 milli-seconds. Display offset -10 dB. (so that an RMS level of -10 dB will show up as 0 dB)
  2. Added the ReaComp filter, with my preferred very fast attack and very slow release settings, increasing the output level and removing auto-makeup -
  3. This is followed by the Master Limiter filter, with default settings.
  4. Simply reducing the threshold on the Master Limiter increases the RMS value - play the audio and adjust. The 5 second window means that you have to play at least 5 seconds for the level to stabilize. 
  5. For those sections of the audio track which are louder, split them into separate items by placing the cursor at the split point and pressing the 's' key. On the separate item, right-click, item properties..., and reduce the item volume. We can also hit the Take FX button at the bottom of this dialog box, and apply per item filters.
  6. If necessary, do extra fades or crops at the end. And then we can render directly to 44.1 kHz mp3 96 kbps mono CBR with quality setting q=2.


2 comments:

  1. Very informative sir. By the way, is reaper still free?

    ReplyDelete
  2. Reaper is not "free", but it offers a trial version without any feature limitations.

    ReplyDelete