Hello,

I need some help identifying the type of audio on a LaserDisc set. As some of you may be aware I am working on a preservation of this set: http://www.lddb.com/laserdisc/35598/168035/Star-Wars:-Coffret-Trilogie Now according to the lddb page it says this set has "Digital Sound" and carries a "Dolby Surround" soundtrack. I am capturing these LaserDiscs with a Pioneer CLD-D925 and Canopus ADVC-55 using the RCA jacks on the D925.

The problem I am having is that I am not sure I have captured the audio properly. I have been looking around the web to find out what the speaker arrangement icon next to the "Dolby Surround" logo on the lddb page means and I finally came upon this webpage: http://www.aracnet.com/~nwolff/theater/surround.html according to this page this set could have 1 of 3 types of audio

1. Dolby Surround
2. Dolby 4.0
3. Dolby Pro Logic

At present I have only captured 2 channels of audio for the whole set. Now its my understanding that this would be correct for Dolby Surround which is 4 channels matrixed down to 2. If this is the case can anyone suggest how I un-matrix the 2 channels into 4 or how I could encode my 2 channel PCM captures as Dolby Digital Surround? However if the audio is not Dolby Surround but in fact Dolby 4.0 does this mean I am missing 2 channels of audio? If this is the case it shouldn't be a massive problem as I have noticed in the past that the capture settings on my system have an option to capture "First 2 channels" or "Second 2 Channels".

I am completely stumped, please help!