On Thu, Jul 30, 2009 at 04:53:25PM -0500, Matthew Woehlke wrote: > Doug Ledford wrote: >> Every system I build still keeps the analog signal cable between the >> CD/DVD and the soundcard. This doesn't help if I try to watch a movie >> as that signal has to be decoded and then played, but for audio CDs >> it is still a perfectly acceptable means of playing the music. So I'm >> not sure where this "CD in is obsolete" comes from. Even the >> motherboard I bought about 2 months ago still has a CD in port and >> the CD/DVD in that machine still has an analog output. > > CD is digital and can be read in digital format by your CPU and sent in > digital to the sound device. This is lossless. > > You want to: > (D->A) do the DAC in the CD drive > (A) toss that on an analog wire > (A/A->D->A) apply an analog volume adjustment (if you're lucky; you > might actually end up doing a ADC, digital volume adjustment, DAC) > (A/A->D) toss that on a different wire that might be digital > (A/D->A) hear it from your speakers > > You could: > (D) read the CD digital data > (D) toss said data to the sound device (losslessly!) > (D/D->A) apply a digital volume adjustment (or maybe analog volume > adjustment after DAC) > (D/D->A) send that, maybe digitally, to your speakers > (A/D->A) hear it from your speakers > > What exactly is better about the first scenario? At *best* you're moving > the analog signal across a longer run of wire (and one that is inside > your computer case with who-knows-what shielding picking up > who-knows-what interference). At worst you've tossed several analog > elements into a process that could have been digital from disc to > speaker cones. > > Seriously... do I miss something? That reading in the data digitally uses non trivial amounts of PCI and CPU bandwidth. If I can't hear the difference between the two modes, then that CPU usage is a total waste of resources. I have other things I want my CPU to be doing. -- fedora-devel-list mailing list fedora-devel-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/fedora-devel-list
