Sony SonicStage (ATRAC)
SonicStage is an audio library manager created by Sony to work with their
MiniDisc devices. The installation is bloated, takes forever and installs
all kinds of drivers and barely-related crap on your Windows. The user
interface is also quite unfriendly (that being said, 4.3 seems friendlier
than 2.0 in the limited tests I did).
But I did not create this page to complain about SonicStage. I am here to
talk about ATRAC, which is Sony's audio compression format, and SonicStage
just happens to be the encoder.
ATRAC - Adaptive Transform Acoustic Coding - started being developed by
Sony in the early nineties as an audio data reduction technique to be
employed in their movie theater audio system - SDDS (Sony Dynamic Digital
Sound) - that encoded 7.1 audio streams in 1168kbps and stored the data
optically next to the film stock sprockets. In this capacity, it competed
with the Dolby AC3 and DTS formats.
Around the same time, Sony was working on a magneto-optical media storage
system called MiniDisc that used ATRAC to compress audio, reducing CD
quality streams from 1411kbps (uncompressed) to 292kbps - or 146kbps in
mono mode. There are several backwards- and forwards-compatible versions
of the ATRAC encoder created by Sony, from v1 to v4.5, and it is said it
only started sounding good in version 3. Other MiniDisc manufacturers
such as Panasonic and Sharp also released their own tuned versions of
In 1999 Sony launched the first major upgrade to the ATRAC format with
the release of ATRAC3. It was launched as a response to the perceived
technological superiority of the MP3 format (similar quality at much
smaller bitrates), so ATRAC3 claims to achieve transparency in LP2 mode,
at 132kbps. There is also an LP4 mode that stores tracks in 66kbps but
with noticeable quality degradation. While being based on ATRAC, it is
not backwards compatible as it includes several coding improvements and
modified algorithms - therefore it will not work with old MiniDisc
players, only with newer MDLP (MiniDisc Long Play) devices.
The next iteration of the format was called ATRAC3plus and launched in
2003, still based on the same underlying technologies but with further
backwards-incompatible improvements. It offered bitrates ranging from 48
to 352kbps and was only compatible with Hi-MD MiniDisc devices (but also
compatible with several other Sony devices such as VAIO cell phones, PS3
and PSP consoles, and Xplod car players).
A parallel iteration of the format is ATRAC Advanced Lossless, in which
an audio stream is encoded in ATRAC3 or ATRAC3plus and the "discarded"
audio data is losslessly compressed and merged to the lossy stream. That
way, players that understand the extra data can play lossless audio,
and older players that do not can play the normal lossy stream. It is
the same idea implemented by mp3HD, WavPack hybrid mode and OptimFrog DualStream.
The latest iteration of the format is called ATRAC9, and is focused on
video game audio for Sony consoles.
Besides being implemented in several hardware devices and software
programs created by Sony, the format has been licensed for other MiniDisc
manufacturers such as Sharp and Panasonic (as mentioned above) and to
Real Networks as the audio compression engine in
Real Audio 8.
You can also try the Sony ATRAC3 ACM codec, available below. It integrates
with the Windows Audio Compression Manager and
encodes to ATRAC3 files wrapped in the WAV container, allowing bitrates
of 66, 105 and 132kbps. Keep in mind this is quite old code and probably
does not reflect the best quality ATRAC3 can provide.
None of the ATRAC versions and iterations has ever been publicly documented,
which in part explains the small popularity the format enjoys outside the
Sony world. There is no VBR encoding at all and no multichannel
implementation other than the completely proprietary SDDS. But the FFMPEG
project reverse engineered and provides decoders for all iterations of
ATRAC in their libavcodec library.
The official ATRAC home page at Sony's web site is available here and
you can see a mirror of the SDDS website at the
Download: SS43E.exe - 36.969kB
Download: SS20E.exe - 37.485kB
Interface: ACM Codec
Download: Atrac3.exe - 148kB
If you have the in_atrac3 Winamp Plugin, please
contribute it to our collection!