soundKonverter and fre:ac

The Linux world plays host to several tools for ripping music CDs, but demanding audiophile users are often dissatisfied with the functionality of conventional rippers: Many of the tools lack important additional functions, such as automatic volume adjustment.

With free programs like soundKonverter [1] and fre:ac [2], you can do everything from ripping and transcoding in a single interface. In some cases, the programs do not provide the functions directly, but instead act as graphical front ends for other audio utilities.

soundKonverter

soundKonverter has been in development for more than 10 years and is continually maintained by the project developers. soundKonverter resides in the repositories of most major Linux distributions. See the documentation for your own Linux distro for more on obtaining and installing soundKonverter in package form.

Once you have installed soundKonverter, you will find the icon in the Multimedia (or Sound & Video) section of your application menu.

The software comes up with a simple window featuring a large list area with information about individual tracks, a menubar at the top, a progress bar at the bottom, and a button for adding media or files. Pressing the button opens a drop-down that lets you select the source of the content you want to edit (Figure 1). You can enter a directory, a single file, an audio CD, or a URL, and you can call up a playlist in M3U format.

Figure 1: The first soundKonverter window you see is simple and straightforward.

Selecting an audio CD as the source medium shows the contents of the CD in a pop-up window in the form of a track list. Check the boxes under the Rip column to select the tracks you want to rip and transcode (Figure 2). A click on the Play icon beside each title starts playback. At the top of the window, enter the general metadata, such as the artist and album, and at the bottom, specify the details for each individual track.

Figure 2: soundKonverter has checkboxes for selecting the tracks to be ripped. If metadata is missing, you can enter the information in the appropriate fields.

After you select the desired tracks, click Proceed. The next dialog lets you define the output format, and the Detailed tab defines the quality or compression rates.

You can also specify how and where to save the transcoded files and whether the software calculates a replay gain. If a replay gain tag is activated, soundKonverter automatically adjusts the volume to ensure that songs from different sources are played at the same volume.

If you want to play back a mix of digital and analog recordings, replay gain reliably compensates for the considerable dynamic differences between the two technologies. After completing the configuration, a click on OK transfers the desired tracks to the primary program window.

You can start the transcoder with the Start button at the bottom of the window. The progress bar and a percent activity indicator under the State column indicate the progress of the conversion (Figure 3). soundKonverter supports multithreading on state-of-the-art processors and can process several files simultaneously.

Figure 3: Thanks to multithreading support, soundKonverter transcodes in parallel.

If you load a file directory instead of ripping an audio CD, soundKonverter skips the dialog for defining the readable data and immediately transfers the available audio files into the specified file directory in the main window. After setting the target format and volume adjustment, begin the conversion by clicking Start.

Profiles

Internally, the program works with profiles that make ripping and transcoding far easier, especially for large music collections. You can access these profiles in the menu from Settings | Configure soundKonverter. The General section has some basic options for the user interface, conversion, and replay gain tool. In the User Interface area, one of the predefined profiles shows in the Default profile selection box.

The settings in the Cover Art group allow the inclusion of cover images. Under Advanced, you can enter metadata for Ogg-Vorbis and FLAC files. In the Backends section, you can define which encoders and decoders are used, which program rips audio CDs, and which plugins you want to activate for volume adjustment (replay gain).

Linux has a nearly unmanageable variety of command-line encoders and decoders, which can sometimes lead to incompatibilities. soundKonverter therefore allows you to check your selection of back ends for optimal interaction. Choose the Backends tab and click Show possible optimizations; the software checks the combination of back ends you have selected and then displays the results in a small pop-up window (Figure 4).

Figure 4: Checking the back-end settings in the soundKonverter Settings dialogs.

If the software is not functioning as expected, call up the logfile under Conversion | View logs. Missing plugins or back ends are highlighted in red.

Volume

soundKonverter also lets you adjust the volume of existing audio files in different formats. To adjust the volume, choose Tools | Replay Gain tool. In the new window, select the directory where the music files are located.

soundKonverter then queries the output formats, and the module enables the formats it supports. All files then appear in a tree view in the title list. You can start the volume adjustment by clicking Force recalculation (Figure 5).

Figure 5: The replay gain tool in soundKonverter lets you adjust the volume of different tracks to match.

fre:ac

fre:ac, developed by Robert Kausch, has been in development for more than 15 years. Despite a low version number (1.0.31a), the cross-platform audio tool is up to date, with support for many formats, multithreading, and a CDDB/freedb connection.

fre:ac provides good performance and an impressive range of features, including support for cue sheets and the ability to extract an audio file from a video recording.

Getting Started

You can obtain fre:ac for 32- and 64-bit architectures as a tarball from the developer's website [2]. The project specifies at least a Pentium 4 or Athlon 64 processor and 512 MB of RAM. The minimum available hard disk space is just 100MB.

After unpacking the archive, move the newly created program directory to a folder of your choice and optionally create a launcher in the menu hierarchy. To start fre:ac from the program directory, click on the freac file.

At first glance, you can see that fre:ac is much more complex than soundKonverter. In addition to the usual menubar and buttonbar, the main window has a list area at the top for the selected audio tracks and an info area at the bottom that displays information on the current track, the selected encoder and decoder, and the output path (Figure 6).

Figure 6: The numerous functions in the fre:ac program window indicate a higher level of complexity than is found in soundKonverter.

To configure fre:ac, select Options | General Settings. The extensive configuration dialog lets you make granular adjustments. For example, you can specify a software encoder in the Encoders section (Figure 7). Unlike soundKonverter, fre:ac includes its own converters and is not dependent on other converters installed on the system. You can access the encoder settings by clicking on the Configure encoder button to the right of the Encoder selection box.

Figure 7: The fre:ac configuration window offers a variety of possibilities to adapt the converter to your own needs.

In the Ripper | CDDB dialog, you can define whether or not to query a CDDB/freedb server for access to cover images, album track lists, and sometimes lyrics, which the software correctly tags to tracks.

Use the Playlists tab to create playlists in the standard M3U format that most audio players can read. As a special feature, the software also generates a cue sheet (see box "No Interruptions").

Pressing OK applies the changes. After loading an audio CD, fre:ac reads it and lists the contents in the main window. By default, it checks the boxes to enable all tracks for ripping. Clicking on a track displays the metadata associated with the track in the information fields at the bottom of the window; you can edit or add to the data as needed.

To create a personal playlist, uncheck some of the individual titles in the list. A click on the Play button in the top toolbar starts reading and converting to the selected target format. Alternatively, you can play back individual tracks by clicking the Play button directly above the list area. Use the buttons to the right to pause, stop, and jump to the next or previous track. If you mouse over one of the entries, a flyout appears with information about the album and the title, including the sample rate and resolution, track length, and bit rate.

After selecting tracks, start the process of reading the CD. In the lower area, the software displays a two-line horizontal progress bar; the upper half symbolizes the progress in ripping and transcoding the current title; the lower half shows the overall progress (Figure 8).

Figure 8: The double bars in the fre:ac info section show the progress in processing the current job. The upper half shows the individual track, the lower half the overall status.

When transcoding, fre:ac creates a separate subfolder for the audio files in the target directory. If you want to transcode different tracks with different encoders or different qualities, highlight them individually and make a choice in the Selected encoder field. If necessary, you can then adjust the encoding quality with Options | Configure selected encoder menu.

Only one track can be transcoded at a time with this procedure; fre:ac then stores the tracks in the subfolder for the audio CD. The software deletes the ripped tracks from the list after completion.

By default, fre:ac uses the existing replay gain settings in the metadata of each track to determine the volume. At the moment, the software lacks a function to adjust the volume itself. When asked, the developer said this feature will probably be available in an upcoming version.

Converting Audio Files

If you want to convert music files from the lossless but memory-intensive FLAC format to Ogg-Vorbis, which is lossy but produces significantly smaller files, you can load them into the list view with the Add audio file(s) button in the upper-left corner of the buttonbar.

Select the target format in the Selected encoder selection box (Figure 9) and adjust the output quality, if necessary; then, click on Start the encoding process. fre:ac stores the converted files in the target directory.

Figure 9: fre:ac offers 14 target formats.

If you select a lossless target format for a lossy source format, fre:ac points out that no quality improvement is expected for the target format, but the file size is expected to increase. The dialog asks if you would like to select a different target format.

fre:ac completes conversions between different file formats very quickly; a single track in the target format appears after just a few seconds.

Playlists

fre:ac creates playlists of the transcoded titles in the standardized M3U format, which most players can process. To generate playlists automatically, activate the Create playlist option. fre:ac creates a playlist for the tracks in the subdirectories corresponding to the albums.

Conclusions

Both soundKonverter and fre:ac are powerful programs for ripping music CDs and converting audio files. Speedy operation and very good results make these two tools stand out. soundKonverter is more appealing for occasional users, but fre:ac offers a significantly greater range of functions – mainly with the large number of configuration options for encoders and decoders.

fre:ac also offers excellent multithreading on modern computers, with configurable parallel processing. As a unique feature, soundKonverter has automatic volume adjustment, a feature that is currently under development in fre:ac. The fre:ac tool offers other unique advantages, such as the ability to create cue sheets or extract audio tracks from video files.