What exactly do CD players with a sampling of 24/192 acheive?


Better Sound.
The D/A converters developed for DVD application are 24 bit devices that can run at 192 KHz. When these readily available and relatively cheap devices are used to read a 16bit CD disc and are run faster than the 44.1 KHz data rate of the CD disc, the result is a higher bandwidth analog signal, where the signal in between the points corresponding to the original 16 bit data on the disc has been smoothly filled in. The so called "Brick wall" filter at 20 KHz used in older CD players can be moved up to a higher frequency well removed from the audio range. This ought to improve sonic performance, and most people agree that it does, although other aspects of a particular CD player design may be as much or more responsible.

By the way, in another post there was some confusion (on my part) regarding the sampling rate for DVD-A discs. The 192 KHz sampling rate is for a Stereo DVD-A disc. Multichannel DVD-A are 96KHz/24bits. But I have never seen a stereo DVD-A, and I don't know if such an animal actually exists.
In some ways the sound appears better, but ultimately, I have heard some very good 16 bit players wipe the floor with most 24/192 upsamplers.

The problem is in the multiplication of the errors inherant in digital. SACD is far greater because it goes back to 1 bit and does not compound the errors the same way.

Most DVD-A didks have a set of high resolution stereo tracks in addition to the multichannel tracks. These can have any standard resolution up to 192 khz/24 bit. I haven't run across one with stereo 192 khz tracks yet, though. So far most have been 96 khz.

I've been dabbling in DVD-A with a Toshiba player the last couple of months. Interesting, but I find I prefer SACD so far, though the DVD-A is pretty good. I don't know if I'm hearing mostly media differences or player differences.
Ghosttrider45...Thanks for the info. The number of options available with new disc media makes it difficult to figure out what is going on much of the time.

In my experience TACET DVD-A discs, available from elusivedisc.com, are the best to reveal the potential of multichannel DVD-A sound.
Yes Dartford, the stereo DVD-A 24/192 does exist! You will find it on 2 or 3 releases of a label called "Surrounded By". Their discs contain both a 24/96 surround mix, and the aformentioned 24/192 version. In order to play the latter, one must select "group 2" before initiating "play" on your DVD Audio or Universal player. This may require the use of a video screen, although the recently released Esoteric DV-50 allows this choice to be made using the front panel readout.