We made a video over at Mastering Explained where I talk about loudness matching when mastering. I demonstrate how to use some available plugins for doing automated level matching. Have a look at the video for the full explanation.
The plugins demonstrated in the video are:
These are all really good plugins that solve a specific use case in an elegant way. For occasional reality checks when mixing or mastering they all work perfectly fine. But for more dedicated mastering work, they have a few problems:
- The plugins need to be within the processing chain itself, and thus have to be disabled before exporting the final master. This will lead to errors when you forget to bypass before rendering, which you inevitable will do at some point.
- The loudness matching is done by adjusting the loudness of the “after” signal, while keeping the “before” signal at a constant level. This is not a good solution from a mastering workflow perspective. To have a productive and predictable mastering workflow you need full control of the levels going into your monitoring system.
- The adjustment of the “after” signal is done continuously when using the automatic modes of the plugins, even while you are listening to the signal. This will change the dynamic content of the signal and make it harder to evaluate the sound.
Problems 1 and 2 can be solved by moving the plugins into the monitoring effect chain within Reaper, and do some creative routing. See the video for more details.
The third problem can’t really be solved as far as I can see, at least not while using the automatic modes of the plugins. It is less of a problem when it is the “before” signal that is constantly adjusted, but it would still be better if the gain would be held static while listening to the signal.
To solve all of these problems, I made some modifications to the AB Level Matching JSFX from TBProAudio.
The changes made to the original plugin are:
- Keep the “after” / “post” / mastered signal at a constant, unchanged level (except for the Output Gain, see below)
- Adjust the gain of the “before” / “pre” / original signal to match the loudness of the mastered signal
- Keep the gain constant while listening to the original signal (when “Autolevel Auto” mode is enabled, as it is by default)
- Add an option to take the “Pre” signal either from the source plugin (original behaviour) or from input 3-4 (the new default). This makes routing and usage simpler when having the plugin in the monitoring effect chain.
- Add a constant Output Gain control to avoid clipping of the compensated original signal. The default is -10 dB which is enough for most situations.
- Set the default RMS window to 2500 ms and have the ITU-R BS.1770-4 prefilter enabled as default.
- Remove / hide some parameters for a cleaner interface
This makes the plugin into a great tool for automated level matching within a mastering workflow.
The easiest way to use this plugin is to install the Mastering Starter Pack for Reaper, and this is the way I would recommend as well.
If you want to install it manually, then follow the steps below:
- Download the AB Level Matching JSFX for Reaper from the TBProAudio website. Look for “AB LM JSFX” under “Reaper JSFX Plugins”. You will need this for the modified version to work.
- Download the modified controller plugin here.
- Unzip both downloaded files and move the “AB_LM_ME_cntrl” file to the “ABLevelMatchingJSFX” directory.
- Open the Reaper resource directory. You can find it from within Reaper by going to “Options” -> “Show REAPER resource path in explorer/finder…”
- Move or copy the “ABLevelMatchingJSFX” directory into the “Effects” directory.
- Either scan for new plugins in Reaper, or close and restart Reaper.
See the video for a more detailed walk-through. But in short:
- Open the Monitoring FX plugin chain.
- Add the “AB Level Matching Control (TBProAudio) – ME Starter Pack mod” plugin. It will be found among the JS plugins.
- Make sure that the monitoring plugin chain has at least 4 channels in the Plug-in pin connector.
- Route the “Before” signal to channels 3-4 in the monitoring path. You can access all channels in the monitoring path as hardware outputs in the routing window for each track.
- Get started mastering and enjoy loudness matched before/after comparison by pressing “POST FX” in the GUI.
I hope you find this useful! Leave a comment below if you have any questions or suggestions!