ATRAC3plus

ATRAC stands for Adaptive Transform Acoustic Coding and ATRAC3 is an evolution of the earlier ATRAC1 system used with Sony's SDDS theater audio system and the MiniDisc format. ATRAC3plus is an extension of the ATRAC3 format. The codec is used with Sony HiMD Walkman device , PlayStation 3 (PS3), PlayStation Portable (PSP), VAIO pocket and ATRAC CD players. It used four times the transform window of ATRAC3, stretching to 4096 samples with a signal split into 16 sub-bands pre bit allocation and MDCT processes.

Originally, data rates of 48kb/s, 64kb/s and 256kb/s were available but recently updates to the Sonic Stage software offered more available bitrates; 48kb/s, 64kb/s, 96kb/s, 128kb/s, 160kb/s, 192kb/s, 256kb/s, 320kb/s and 352kb/s, although using the newer rates is not recommended with older hardware, especially MiniDisc. A Sony-funded study found that ATRAC3plus at 64kb/s matched or surpassed the quality of AAC at 96kb/s or MP3 at 128kb/s. Independent tests may come to completely different results however, and so these figures should be taken with a pinch of salt.

Please also view our Glossary entries for..

• ATRAC1
• ATRAC3
• ATRAC
• ATRAC Advanced Lossless
• MiniDisc
• CDA
• Lossy Compression
• Lossless Compression
• Codec
• Walkman
• SDDS

Some interesting ATRAC-related articles from the AfterDawn archives include..

Sony to dump Connect music service - (August 31st, 2007)
Sony acknowledged that its proprietary ATRAC music format was a market flop by shutting down all its Connect music stores and making its devices compatible with other formats.

Sony kills off ATRAC and SonicStage with latest MP3 player - (April 28th, 2007)
The Sony B100 series of portable MP3 players killed off the ATRAC format.

Sony admits ATRAC was a mistake - (January 23rd, 2005)
Ken Kutaragi has stated that Sony has missed out on the sales of MP3 players and other gadgets by sticking to proprietary formats such as ATRAC.

Sony to add MP3 support to its portable music players - (September 23rd, 2004)
Sony confirmed plans to add MP3 support to its players, loosening its reliance on the proprietary ATRAC format.

Sony Connect music service launched - (May 5th, 2004)
Sony opened its Connect music service which used the ATRAC format for downloadable music files.