MacMP3Gain

MacMP3Gain is an AppleScript Studio application which brings an Aqua GUI to the command line version of mp3gain, a utility that performs statistical analysis to determine how loud the MP3 file actually sounds to the human ear and performs lossless volume adjustments. MacMP3Gain is free and open source. You may download either the application itself or the entire project including the source code.

Warning

MacMP3Gain modifies MP3 and unprotected AAC files with no provision provided to undo the changes. I would highly recommend a full backup of your MP3 library prior to running mp3gain on them.

Additionally, the new "iTunes Plus" files may be corrupted by the current version of aacgain (the underlying program included in MacMP3Gain). Please make backup copies of your music library before running MacMP3Gain.

History

DateVersionDescription
22-Dec-20112.1Fixed mixed up Radio Gain Mode and Undo buttons. Fixed progress tracking. Built on Mac OS X 10.6 Snow Leopard - should run on OS X 10.7 Lion (untested).
18-Aug-20112.0Added Undo button.
31-Aug-20061.9Added link to Intel native version (**) from French student Maxime Hadjinlian.
20-Dec-20051.9AAC gain and Tiger support. This version runs on Mac OS X 10.3.x and 10.4.x and handle non-protected AAC files
09-Nov-20031.8Fixed playlist feature for iTunes 4
03-Nov-20031.7Updated to mp3gain 1.4.3. Changed behavior when "Allow Clipping" is unchecked to enable the "auto-clip" feature of mp3gain.
28-Feb-20031.6Minor GUI fixes to disable "Be Nice" and "Target dB" and "Album/Radio" buttons while running. Added documentation to archives.
26-Feb-20031.5Added "Be Nice" option care of Michael Heinz. Added "Cancel" button.
23-Feb-20031.4Added "Target MP3 Gain Value" option. Added preferences file to save previous dialog settings.
20-Feb-20031.3Fixed program hang when "Allow Clipping" checkbox was unchecked.
18-Feb-20031.2Added "Process Sub-folders" option to process all folders below the selected folder.
15-Feb-20031.1Added "Choose Playlist" button to allow selection of an iTunes playlist for processing. Also added new icon from Mark Lorrigan (thanks Mark!).
16-Jan-20031.0Initial release. Contains mp3gain version 1.3.3.

Downloads

Thanks to Maxime Hadjinlian for building an Intel-native version which can be downloaded here:

Older Versions

Copyright / License

Copyright (C) 2003-2014 Bery Rinaldo

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

Based on aacgain version 1.4.0
copyright(c) 2004 David Lasker, Altos Design, Inc.
derived from mp3gain version 1.4.6
copyright(c) 2001-2004 by Glen Sawyer

MP3Gain/AACgain web sites:
http://mp3gain.sourceforge.net/
http://altosdesign.com/aacgain/

uses mpglib http://www.mpg123.de
AAC support uses faad2 http://www.audiocoding.com
mpeg4ip's mp4v2 http://www.mpeg4ip.net

Linux build system by: Prakash Punnoor
Icon contributed by: Mark Lorrigan
"Be Nice" addition by: Michael Heinz

Credits

Glen Sawyer for all his development of MP3Gain and to David Lasker for the aacgain addition. Special thanks to Mark Lorrigan for his work on a fancy icon for MacMP3Gain. Also, thanks to Michael Heinz contribution of his "Be Nice" feature.

System Requirements

Mac OS X 10.2 or higher and some MP3 files. iTunes 3 or higher required for playlist support.

Usage

Double-click on the application icon. You will see the following dialog window:

Click on the Choose Folder button to select a single folder with MP3 files in it. This is typically a single album from one artist under the iTunes folder. A dialog box like the one below will allow you to choose a folder.

If you prefer to select an iTunes playlist, click on the Choose Playlist button. If iTunes is not running, it will start running (this is so that MacMP3Gain can ask it for its list of playlists). A dialog box like the one below will allow you to choose from a list of your iTunes playlists.

After selecting a folder or a playlist, simply click the Start button. While the process is running, the button changes to a Cancel button to stop the procerss. The mp3gain program takes several minutes to analyze the files, then modify the gain for each file. A status message will be shown near the bottom of the dialog box:

When the process is complete, the "barber pole" busy indicator will disappear and a message stating that the processing is complete will be shown at the bottom of the dialog box. That's it...you can choose another playlist or folder, or quit.

Controls

This section attempts to describe each of the three controls availble on the dialog window shown above.

Album Gain Mode

This mode analyzes all the selected files, then applies the same gain offset to all the files. This preserves the differences between songs keeping the "artistic variation" of the album intact. This mode is normally used when running mp3gain on a single CD's worth of music.

Radio Gain Mode

This mode analyzes each file individually, then applies a unique gain offset to each file. This works well when songs have come from a variety of sources or from compilation CDs. If you listen to your music in "random" mode, then this might be preferred.

Allow Clipping

Clipping means that some value in some frame of the song is greater than +/- 32,767. If any value goes over that, a 16-bit decoder cannot calculate the output wave sound, and it results in a distorted sound. In theory, this sounds like a bad thing, however in practice, I have not heard any ill affects from allowing clipping to occur. I normally leave this option on although I do not claim to have "golden ears", either.

With this box unchecked, the gain offset is adjusted to ensure that no values go out of range (this is the so-called "auto-clip" feature of mp3gain which uses the "-k" command line switch).

Process Sub-folders

When enabled, this option processes all folders containing .mp3 files at or below the selected folder. Each folder is processed separately so that the Album Gain Mode will work as desired (assuming that each album is in a single folder). With this option selected, users could process their entire library with one run.

Target MP3 Gain Value

When enabled, this option allows the user-entered target MP3 gain value to be used rather than the default of 89 dB. This adjustment should be used with care as adjusting this higher could cause clipping to occur when playing MP3 files after they've been adjusted. If you're not sure, then leave this alone.

Be Nice (Reduce CPU Priority)

When enabled, this option reduces the priority of the sub-process using the Unix "nice" command. This is useful when you're running MacMP3Gain while trying to use your Mac for other tasks.

FAQ

Q: Can I undo the changes that mp3gain does to the files?
A: No. See the warning above. Make a full backup of your MP3 library prior to running MacMP3Gain.

Q: Why are the songs so quiet after I run mp3gain?
A: The command line program mp3gain has a default of 89dB which sounds quieter than many newly ripped MP3s from "modern" CDs. This is now adjustable with MacMP3Gain although adjusting this higher may mean that you add more clipping.

Q: I am running MacMP3Gain but I don't hear my MP3 files playing. What's wrong?
A: MacMP3Gain is not an MP3 player, it analyzes and modifies MP3 files to normalize the perceived volume level of the songs so that when you play them with an MP3 player, you don't have to adjust the volume level for each track.

Q: I am running Mac OS X 10.1, how can I run MacMP3Gain?
A: You can install the Developers Tools that came with your Mac and download the full source to MacMP3Gain (see above) and to the command line mp3gain that I built for Mac OS X 10.2 and build it all yourself. If someone does this, I'd be happy to help you and post it here once it's complete.

Q: I have used the command line version of mp3gain and it has a lot more options than MacMP3Gain. Can you add support for other options?
A: I started with the idea to keep this very simple, but I'd be more than happy to consider other options if enough interest is generated. Just e-mail me at:


This page was last updated on: Sun Jan 19 07:29:01 PST 2014