Real-time AC3 encoding with SPDIF using ffdshow or AC3Filter

[adoniscik]

Does it make sense to do this with a consumer sound card (e.g., Creative Audigy)? When SPDIF is used, I know that the receiver does the D/A conversion. How about with regular PCM? If the sound card does it, then maybe encoding to AC3 with a high bit rate would sound better, as the conversion would be deferred to the receiver.

[Tony Maroni]

I think this depends on the connection you are using.

My PC is located in a different room than the receiver, so i got quite some cable length.
It's really easier to use one cable for the SPDIF connection ( you know, it's digital, there won't be any flaws, if the connection gets bad because of cablelength it wil just stop) than 6 (long) quality wires for a good analog connection.

But if you can choose, i would always prefer the original format, because every conversion between two lossy formats gives out reduced quality.

It's different with PCM, because this is no lossy format (it's kind of a wav-format). The soundcard sends this signal to their D/A, or via SPDIF to the D/A of your receiver.

But to be honest, i've tested both conections with my cheap Audigy LS and i can't tell the difference! I've also tested on-the-fly AC3 encoding and for my ears, it also sounds great...

So choose what's suitable for you, maybe test for yourself...