ePAC is a new version of the Lucent Perceptual Audio Coder (PAC), an audio compression algorithm with the highest-quality audio at the lowest bit rates. At 128 kilobits per second, ePAC offers CD-transparent stereo sound.
Developed by Bell Labs ePAC uses psychoacoustic modeling to compress music in a way that is not noticeable to the ear. Music is compressed at a rate of 11 to 1, thus reducing the transmission time/bandwidth and storage by the same ratio, while still retaining its fidelity. Several recent improvements in ePAC have pushed its performance levels to new heights, including: ePAC's improved quantization and coding, allowing higher quality audio at lower bit rates, and ePAC's improved psychoacoustic modeling from Bell Labs research, which provides CD-transparent sound at 128 kbps. ePAC's variable bit rates and superior audio quality allow the coder to be used in multiple bandwidth applications.." NULL