PCM, as it turns out, is uncompressed 2-channel sound. To get sound coming from all 5 speakers, I need to either turn off DTS-Connect or DDL, then set the sound card to PCM. The surrounds stay quiet and the center stays quiet, even if it's in DTS or Dolby Digital.

Encoding a stereo source into Dolby Digital won't magically add another 3 sound channels, thus sending sound out of all speakers. But if that sound was being encoded to either Dolby Digital or DTS on the fly, shouldn't that add sound to the other channels? I thought it would, for years, but I think now that I was wrong. So, with a 2-channel source, like a stereo MP3 file, I'd only expect sound to come from the left and right front speakers. This was when I realized that I had been making incorrect assumptions for years. But when I play MP3 files in Windows Media Player, or Winamp, or iTunes, sound only comes out of the left and right front speakers.

My Z-5500 receiver box tells me that any sound I hear is 'DTS.' Great. So, with new speakers in tow, I used my optical cable to go into the Z-5500 and chose to enable DTS-Connect. Also, there was a fantastic deal on the Z-5500 setup. I recently purchased the Logitech Z-5500 speaker set because my Yamaha speaker system was getting long in the tooth. It was like Soundstorm, but with another option!

Now I'd be able to encode, on the fly, to my choice of either Dolby Digital or DTS. Then, along came the HDA/Auzentech X-Plosion, which not only had DDL, but DTS-Connect as well. If memory serves me right, Soundstorm was discontinued, so getting another DDL-enabled sound option for my computer was no longer an, uh, option. I got the satisfaction of seeing the Dolby Digital light on my speaker receiver box light up no matter what sound was being played on the computer. The Yamaha speakers I had (5.1) had a receiver that would decode both DTS and Dolby Digital, so getting sound from my computer that was all 'Dolby Digital' made sense to me. I first heard of Dolby Digital Live (DDL) back when nVidia motherboards featured their Soundstorm.

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