The Envy24 is a great audio card chipset, and is what our recently reviewed Chaintech AV-710 uses. VIA Arena has written an in-depth guide on the Envy24 and the control panel which is included in the drivers.
The VIA Envy24 Family driver package supports the controllers in the middle range that fall between those ends of the market. VIA manufactures 5 audio controllers that have been developed for cost effective surround sound, media centres, game consoles, internet appliances, consumer electronics, notebooks and high end motherboards. The differences in the resolutions and sampling rates between the controllers means that VIA offers a range of options so that the most suitable level of performance and bit accuracy can be selected by both manufacturers and consumers alike, depending on the level of audio quality they want and need.
Check out the full guide over at VIA Arena.