Replay Gain implementation for Sansa Fuze
What is it?
Replay Gain is a method for keeping the perceived volume level constant during playback of diverse content. Typically, Albums are mixed and targeted to differing average volume levels. During playback in shuffle mode there can be wide differences in the track output volume, causing the user to make frequent corrections to the volume level.
Sansa Fuze’s Replay Gain is a method whereby average volume playback level is kept consistent automatically.
The difference in the volume level vs. a reference (typically 89dB) is stored in the track metadata fields and is used by the Sansa Fuze to adjust the volume control to produce a uniform level. It should be noted that our implementation does not modify the actual music samples. It extracts the level adjustment in decibels (dB) from track metadata and applies an adjustment to the output volume control.
Software on the user’s computer analyzes the tracks to produce the Replay Gain values for embedding in the metadata. The Sansa Fuze implementation follows the 2001 proposed Replay Gain standard which is detailed at:
More information on ReplayGain can be found on Wikipedia at:
The Sansa Fuze’s implementation was tested to work for all of its supported non-DRM formats (MP3, WMA, OGG, FLAC) using MediaMonkey. MediaMonkey is a free media manager application which can be downloaded at:
Replay Gain for DRM Protected tracks (ie Rhapsody / Napster/ Netlibrary/ Audible) as well as SanDisk SlotRadio content is not supported.
The subscription sites may apply their own track leveling.
SanDisk SlotRadio content has been volume leveled in advance at a reference of 89 dB.
How do I use Replay Gain?
On your Computer:
First you need to analyze the tracks in your library. Download the MediaMonkey software and add your Music collection to the Manager.
Configure the MediaMonkey “Volume Leveling” options under Tools>Options>Volume Leveling. You can specify to also analyze the Album volume (otherwise known as “Audiophile Volume” ) when doing the Track Analysis. “Album volume” computes an average correction for all the tracks that comprise an album. Album Gain is supported by the Fuze as well as the Track Gain method.
Select your music files and then select “Tools> Analyze Volume”. This will perform the volume level analysis based on the options you have set up. It will write the Replay Gain values to the ID3 tag for MP3, Vorbis Comments for OGG or FLAC, or WMA header for WMA content. This action can take a long time depending on the size of your collection. It’s best to run the program overnight to do a large collection. You do not need to “Level Track Volume” which will apply the correction to MP3 files’ data.
Note: Fuze does not support APEv2 tags used by MP3Gain.
On the Player:
Once your files have been analyzed you can transfer them to the Fuze Player.
To enable/ disable Replay Gain: select Music Options>Replay Gain. Select the Mode to be “Song”, “Album”, or “Off”. The Off setting will not apply any corrections to the volume level regardless of the Replay Gain values found. If Album mode is selected but Album Gain values are not present, Track Gain values will be used if available.
There is a “ Pre-Gain ” setting which allows you to adjust the overall Playback Volume level upward to compensate for the “average” level of your library’s track adjustment. For example, if your collection is mainly classical or soft songs, you should use a Pre-Gain of 0 dB, since the average level is likely to be close to 89 dB. For Hard Rock / Hip Hop collections, the Replay Gain values will be more negative, (meaning the song is above the 89dB target) like -8 dB. In this case, higher Pre-Gain level such as 4.5 dB can be used. You can compensate the overall gain level upward in 1.5 db steps up to a maximum of +12 db. Pre-Gain is NOT applied to tracks that have no Replay Gain values available. Pre Gain is helpful for matching Replay Gain adjusted content with Rhapsody or Napster Protected Content that may be both present on the player.
Line Out mode:
Replay Gain adjustment in Fuze’s Line Out (or Docked) mode is supported. The maximum total positive line-out adjustment is 4.5 dB, limited by the hardware. In Line Out mode it’s recommended to set the Pre-Gain to “0db” to allow headroom for the adjustment.
Viewing the Replay Gain values on the Fuze:
You can conveniently view the Replay Gain values for your currently playing track by accessing the Music options (down arrow) and scrolling to the second page of the “ Track Info ” screen. If there is no Replay Gain value present these items will not be shown
Message Edited by slotmonsta on 04-08-2009 05:13 PM