Other than that single change, the 5.1 mixes are exactly the same, which is WONDERFUL - the AC-3 LD's and DVD releases (both the DTS and AC-3 versions) all had mixes that had been altered from the theatrical mixes - the AC-3 Dolby Digital mixes on DVD had some of the LFE bass re-directed to the main channels (a Dolby recommendation) and the Right Rear channel had a broadband 90-degree phase shift applied to create a better Dolby Pro-Logic compatible downmix for those consumers who have to use the 2-channel outputs of their DVD player: the unfortunate side-effect is that side-wall imaging is destroyed, as is any imaging between the rear speakers since one channel is shifted by 90 degrees in phase (Dolby recommends the 90 degree phase shift always be used for best 5.1 to 2 channel downmixing except in cases of a phase-coherent mix - then a separate 2-channel mix should also be supplied on the disc, which is something that Paramount and Fox routinely do so that their 5.1 mixes are not altered for DVD.) The JP & LW surround mixes on LD and DVD were not as aggressive as the DTS-6 (APT-X100 encoded) theatrical mixes - certain sounds were missing entirely or buried so far down in the mix that you could barely hear them. Imaging seemed to suffer too, especially in scenes like Nedry's car with the rain on the roof - you can hear the rain above you, almost as clearly as if a speaker were placed on the ceiling, in the original DTS theatrical and LD mix and now on the Blu-ray. Nor did the alternate AC-3 LD and DVD mixes seem to have as aggressive dynamics and headroom as the DTS-6 theatrical/DTS LD mixes. The DTS LaserDisc of Jurassic Park was the very first DTS LD released and DTS used the same (+20db headroom Dolby SR 6-track 35mm Full-Coat Mag) master to encode the DTS LaserDisc as they used to make the theatrical DTS-6 CD-ROM discs.

do you have ANY surround speakers hooked up?

I recently purchased a Singapore import of Jurassic Park ...