There has been some confusion over Windows Vista and how it relates to various audio formats. Vista does indeed have a reworked audio stack with a lot of cool new features like Room Correction, Bass Management and Loudness Equalization.

One of the negatives however is how Vista handles copy protected audio. It really shouldn’t be as Vista is not saddled with anything extraordinary in the industry.

One rumor has Windows Vista disabling S/PDIF or the Sony/Philips Digital Interface Format. S/PDIF is a popular digital multi-channel audio input/output format probably used by your DVD player and Home Theater receiver. It’s also used by PC 5.1 speaker systems and PC sound cards. The optical output on your Sony PlayStation3 and Xbox360 is S/PDIF. The format appears in either the digital coax or optical (fiber optic) connection. But S/PDIF is not a ‘protected’ format, it’s a clear digital pass through which is exactly what content providers want to avoid and is likely to be phased out in the high definition future. Through S/PDIF there is nothing stopping a device from recording an exact digital duplicate of original material.

High resolution multi-channel audio formats like SACD (Super Audio CD) and DVD-Audio were designed to prevent this by not being compatible to the S/PDIF format. You can only output audio from an SACD/DVD-Audio source via analogue or another ‘protected’ format such as HDMI.

Herein lay the confusion over Vista and S/PDIF. A comprehensive article was published that goes over many of the copy protections issues concerning Vista.

It gave rise to the rumor that Vista would disable S/PDIF but many people are already using Vista over S/PDIF connections to their 5.1 speaker systems and they’re feeling no pain.

The Facts

Vista cannot pass ‘protected’ content through S/PDIF. This shouldn’t come as any surprise because no device should be able to pass ‘protected’ audio content through S/PDIF as it’s not a protected format.

As the article explains – if you were to pop in your SACD of Pink Floyd’s Dark Side of the Moon and expect to hear anything over your Vista PC you’re in for a disappointment. SACD is a protected audio format that will work through HDMI but not through an optical or coax digital audio connector.