SD2 to MPA: Convert Audio from SD2(Sound Designer 2) to MPA(MPEG Audio) with River Past Audio Converter, SD22MPA converter, conversion

What is SD2?

SDII (Sound Designer II, sometimes seen abbreviated as SD2) is a monophonic/stereophonic audio file format, originally developed by Digidesign for their Macintosh-based recording/editing products. It is the successor to the original monophonic Sound Designer I audio file format.

An SDII file can be monophonic or stereophonic. When stereo is used, the tracks are interleaved (sample-001-left, sample-001-right, sample-002-left, sample-002-right, etc.) Files also store sample rate and bit depth information.

The SDII file has become a widely accepted standard for transferring audio files between editing applications. Most Mac CD-ROM writer software, for example, specifies SDII or Audio Interchange File Format as the file format needed when making audio CDs.

The SDII file has also become accepted among personal computer audio application developers. This makes transferring audio from Mac to PC platforms much easier. When used on a PC, the file must use the extension of ".sd2".

To convert SD2 files to other audio formats, please make sure Apple QuickTime is installed.

What is MPA?

There are three "layers" in the MPEG-1 Audio specification.

In MPEG Audio Layer-1, a simple 32-subband audio compressor using a floating point representation for subband samples. Resolution and scale factor are stored for groups of 12 subsamples. MP1 is only used for Philips DCC Digital Compact cassette with data rates of 384 kbps.

Both MPEG-1 and MPEG-2 files use MPEG-1 Audio Layer-2.

MPEG-1 Audio Layer-3 becomes the widely popular MP3.

MPEG.ORG is an excellent source for additional information on MPEG format and usage.

To encode MPEG Audio, you will need River Past MPEG-2 Booster Pack in addition to your audio software.

Additional Requirements

To convert from SD2(Sound Designer 2) to MPA(MPEG Audio) audio with River Past Audio Converter, you must have River Past MPEG-2 Booster Pack installed.

Launch River Past Audio Converter

Once River Past Audio Converter is installed properly, launch Audio Converter.

Add File

Click on the "Add" button on the tool bar. The standard file open dialog appears. Select "SD2 - Sound Designer 2" in its "Files of type" combo box.

Select the file you want to convert and click "Open". The file will be added to the conversion file list.

Note: To convert from SD2 files, you must have Apple QuickTime installed.

River Past Audio Converter

Select Output Format

Use the setting panel on the bottom of the window to control the output format. Click on the toggle to the left of the "Format" label to expand the panel. Select "MPA - MPEG Layer-2" as the "Audio Type".

You can change the sample rate, channel (stereo or mono) and bits/sample, and bitrate.

Note: The MPEG-2 Booster Pack must be installed for the "MPA - MPEG Layer-2" output option to show.