I2S

The I2S Audio Interface provides a bidirectional, synchronous, serial interface to off-chip audio devices.

The I2S or Inter-IC Sound Standard was developed by Philips to allow audio
data exchange between converters, filters and digital input/output interfaces.
The serial interface is a three-wire bus that contains a line for two timemultiplexed
data channels (Data), a word select line (L/R clock), and a clock
line (Bit Clock). The standard also dictates that the actual audio data be
delayed by one Bit Clock period from the L/R clock.

 

This is the protocol used inside CD players to connect the drive and the DAC.

It is a true computer protocol:

bidirectional: the devices can communicate with each other

signal (audio) and timing are send as data.

 

Compared with S/PDIF this protocol has the advantage of sending both the timing information and the signal as bits. This makes the receiver insensitive to input jitter.

 

In principe a connection between a PC and a DAC using I2S instead of S/PDIF would be an improvement as it eliminates input jitter. As far as I know, there is no sound card delivering I2S output and very few DACs with I2S input

 

More: http://www.interfacebus.com/I2S_Interface_Bus.html

 

DAC with I2S input:

 

April music Stello DA100 Signature

North Star Design

Zero One