Hi:

By Audio CD I understand what is properly called CD digital audio (CDDA) or just Red Book. The first optical drives had an analog output to send the audio signal to the sound card. At least cheap computers, used only this output as a source for the audio signal. Time went by and now in every PC desktop computer, no matter its price, audio is taken from the drive data bus, perhaps prompted by the fact that some optical drives no longer have an analog output.

Could you tell me the approximate year when this shift towards "digital extraction" took place? More specifically, which one of these two approaches was the usual thing in low-end computers by the year of 2004?

Theres 3 ways audio dat can get from a CD/DVD drive to the sound card-

Digital out
Analog out
Over the IDE/SCSI/SATA/SAS bus.

Analog out was by far the most common, and was decoded to an analog signal in the CD/DVD drive. Digital out just passed the digital signal to the sound card.In 2004 you would still get some new systems with a digital or analog link from the CD/DVD drive to the sound card, but it was pretty uncommon by then.

Removing the analog or digital cable saved the big manufacturers a few cents a unit. When you make millions of units, a few cents a unit can make a big difference.

IIRC the move toward using the IDE/SCSI/SATA/SAS bus and deleting the analog or digital cable started in the late pentium MMX/early pentium II days (1998-1999).

Thanks. I had always watched that connector labeled DIGITAL OUT in these drives and wondered why they did not use it.

I have the last release (2004) of cdcd, which by now I'm convinced was not thought for data transfer through the optical drive bus. Like always you such a good source of information.