Since my last PC refresh in March 2005 I have been using Dolby-Digital Live provided by the Intel P4 Desktop board D925XECV2. This motherboard has the Realtek ALC-880D so the hardware takes care of the DDL encoding. The D925XECV2 will do analog 7.1 output, however I decided to go with the toslink optical output to a seperate Dolby/DTS/PCM 5.1 decoder. After the Realtek HD Audio drivers do their job, the Intel Audio Studio v1.52 (Sonic Focus) massages the digital audio further before its conversion to photons...
The optical output goes to a computer-grade Creative Inspire GD-580 5.1 decoder/speaker system. Took a while to get a good set of WHQL Realtek v1.51 drivers to go with the WinXP KB888111 (SP2) hotfix for HD Audio support. Now that is all sorted out I am quite happy with the on-board sound provided by the Intel D925XECV2 motherboard. Allows any 2-channel DOS game executing under the NTVDM or DosBox to have 5.1 surround sound. Better sound than the original DOS platform, with more choice for sound card emulation and MIDI support.
Side benefit is bit-perfect 44,100kHz transmissiion down the optical cable with auto adjustment for 48,000kHz output from DVDs. The S/N of the audio output has a limiting factor of the external Creative decoder box DACs and circuitry. The ALC-880 digital output has around a ~100dB S/N ratio, don't know what the Creative GD580 decoder is but the unused DACs on my Intel D925XECV2 motherboard have a published S/N ratio of around 86dB.
Some have raved about the NVidia SoundStorm DDL of yore - the Intel/Realtek solution is still being sold and works quite well for the WinXp environment. Now that Microsoft has 'deprecated' 😳 the Creative propreitary APU and EAX sound effects in Vista, it looks as if they have made Intel happy that the extra cores in the duo and quad core CPUs will now have something useful to do while keeping those lazy extra cores working... 😁
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