Volume Leveling

Volume Leveling

Introduction

Volume Leveling automatically adjusts the playback volume in order to maintain a consistent level regardless of the source material. Many people have Volume Leveling enabled all of the time as a way to minimize the need for manual volume adjustments. Others only use it for parties, radio, or mixed playlists where volume level differences from track to track are more severe. Roon's volume leveling implementation is based on the EBU R128 standards, and we follow the recommendations made by the Music Loudness Alliance. Before Roon can make adjustments, it must have some information about the loudness of the materials and its peak values. This information is obtained during Audio Analysis.

Enabling Volume Leveling

Volume Leveling is not enabled by default. You can find settings related to Volume Leveling on the Zone Settings screen.



Roon supports four Volume Leveling modes:
  1. Off - disable volume leveling for this zone.
  2. Track - Performs adjustments on a track-by-track basis. This produces the most consistent volume level during a playback session, but may result in unpleasant jumps in volume during playback of a gapless album.
  3. Album - Performs adjustments on an album-by-album basis. This means that the entirety of an album plays back with the same adjustment, and there are no perceived volume jumps at track boundaries.
  4. Auto - Uses track adjustments when playing adjacent tracks from different albums, and album level adjustments when playing adjacent tracks from the same album. 
The "Volume adjustment when loudness is unknown" setting specifies a volume adjustment that should be applied when Roon does not have advanced knowledge of the loudness of a track, for example when playing a track that has not been analyzed yet, or an internet radio stream. This setting prevents large changes in volume when transitioning from the content of known loudness to content of unknown loudness. The default of -5dB represents a reasonable compromise--since Volume Leveling makes almost all material quieter.

How Volume Adjustments are applied Adjustments performed for the sake of volume leveling are simple gain adjustments--the audio signal is multiplied by a constant gain value. Currently, the adjustment is applied within Roon's DSP Engine, but it's likely that future Roon Ready devices will support volume leveling in hardware. You can see exactly what is happening using Signal Path:



If a positive gain adjustment would cause some part of a track to clip, the gain adjustment is modified to avoid clipping. This reasoning uses the "true peak" value captured during audio analysis. This is fairly rare, since positive gain adjustments are uncommon. Per R128 recommendations, Roon targets a final loudness of -23 LUFS. This is a fairly quiet level, thus Volume Leveling may prompt you to increase volume elsewhere in the system to compensate.

Viewing Volume Leveling Information

You can see volume leveling information on the File Info popup. This can be accessed by selecting "View File Info..." for a track in your library.



The "dB" numbers represent the volume adjustment that will be necessary to adjust this track or album to the target level of -23LUFS. The "dbTP" numbers represent the "True Peak" level for the track or album. The "Dynamic Range" value reflects the R128 "Loudness Range" for this track. For more information, [[see here|Dynamic_Range]].

Using Loudness Data in REPLAYGAIN tags
ReplayGain is an older volume leveling system than R128. It is different in a couple of key ways:
  1. The analysis process uses a different algorithm, so it produces different adjustments
  2. ReplayGain targets a final volume level that's 5dB louder than R128's target of -23 LUFS
  3. ReplayGain information is often written into REPLAYGAIN_* tags in media files
Since many files out in the world already contains these tags, Roon supports making use of that information when it's present. (Note that in many cases, REPLAYGAIN_* tags may contain R128 measurements that have been adjusted by 5dB to compensate for the differences in target level. This doesn't present a problem--just something to be aware of!)

Roon supports the following file tags:
REPLAYGAIN_ALBUM_GAIN
REPLAYGAIN_ALBUM_PEAK
REPLAYGAIN_TRACK_GAIN
REPLAYGAIN_TRACK_PEAK
REPLAYGAIN_REPLAYGAIN_REFERENCE_LOUDNESS
 When REPLAYGAIN_REFERENCE_LOUDNESS is not provided the *_GAIN tags are interpreted relative to an assumed target of -18 dBFS. To turn on this support, go into Settings -> Library -> Import Settings, then enable one or both of these options:



    • Related Articles

    • FAQ: What's volume leveling?

      Roon analyzes your music files using the ReplayGain algorithm. Roon also uses volume leveling information provided by TIDAL for their streaming content. If volume leveling is enabled, Roon will automatically adjust the volume to maintain a consistent ...
    • Audio Analysis

      What is Audio Analysis and how is it used? During audio analysis, each file in your library is analyzed in order to extract information about their audio content. Data extracted during audio analysis is used for several purposes: Volume Leveling ...
    • Zone Settings

      The Zone Settings screen is used to access zone-level settings like zone names, crossfade, volume leveling, and volume limits. You can access the Zone Settings screen for a zone, like this: 1. Click the icon for the current zone to show the zone ...
    • Zone

      Think of a zone as a room in your house, or as an output device that you use to play audio. Roon is a multi-room system, so it supports playback of music to one or more Zones. The very bottom area of Roon's user interface, called the footer, is ...
    • Signal Path

      When we set out to create Roon, we felt very strongly that users should have access to honest and precise information describing how their software and hardware devices are performing audio playback. We also felt that great audio hardware should be ...
    Ask the Roon Community
    Thousands of Roon subscribers and audio enthusiasts are chatting over on our community site right now, join them! You don't even need a Roon subscription to sign up.



    Something you can't find?
    If you're still stuck, don't hesitate to let us know and we'll get back to you as soon as we can.