Jurassic Park AC3 vs. DTS



I remember late in 1994 when the LD of Jurassic Park was released. It only had the PCM tracks then, and I remember having some friends over that night. Back then I'd had my Kenwood/Boston Acoustics THX setup for about six months and the Terminator 2 box set was the current champion in the insane bass department. Pizza was the food of choice for this Jurassic event, Los Altos Delight if I remember correctly, it tastes like chicken! Well since I made an event of out the whole LD release I decided to live dangerously and crank the volume it to -7dB. The bass was ridiculous, the dinosaurs actually were stomping around in my living room! Everything was loud, it was just hilarious, we felt like adolescents, I don't want to grow up! Anyway, half way through the T-Rex rampaging on the Jeep scene my unhappy neighbor starts pounding my front door, he's pounding and pounding for several minutes because I can't hear him!! The door is buckling, he's still knocking and the T-Rex is still at it. The film quiets down after a while, and thinking it is a cool surround effect, one of my friends says what thats sound? Ohh, my its the front door. So I pause the film and go and open the door. My unhappy neighbor says its so loud that he can't even hear his own TV and if we can turn it down blah blah blah, when I tell him "Ohh we're just watching a movie" he gets this frightened look on his face and says "thats your TV?"

That was four years ago and that neighbor still hasn't moved. I would of! The Jurassic Park PCM LD reigned supreme for many years and then came discrete 5.1 and the film was re-released in AC3 (Dolby Digital) and DTS. By now I had upgraded my Kenwood THX preamp to a Lexicon DC-1 and purchased the DTS version of Jurassic Park. The DTS version is 10 times more outrageous than the old PCM LD. Ohh man, listening to it at -25dB is out of control.

DTS vs AC3
DTS's 1.5 Mbps bitrate is almost four times greater than AC3's 384kbps rate. The press was hyping DTS as being superior and everyone thought "heck, more bits means better sound." I had played with a Dolby AC3 encoder at different bitrates in the past and I had learned some of the badness that audio compression can cause. In my tests I found the high frequency foley effects became more muffled as the bitrate was lowered from 640kbps down to 192kbps. Some of the sizzle in sound effects and music disappeared.

I had a friend come over and he brought his AC3 LD of Jurassic Park. Two laser disc players were hooked up so we could quickly A/B between the AC3 and DTS versions. We synced up the two different discs of Jurassic Park and our comparison began.

First off the levels weren't matched, so when we A/B'd about 3 or 4dB of volume had to be adjusted for. Next we noticed what we had read, the bass and surround channels were cranked up about +3dB on the DTS disc. These differences made the test difficult. Trying to be critical about the sound when the sound is just different is not really possible. The DTS version had more detail in the surround channels but that is just the difference in surround levels and not necessarily a deficiency of AC3. We listened to foley, we listened to music and nothing. When listening to Nedry talk to Bogsworth at the out door restaurant I heard some funniness in Nedry's voice, it was a mild sort of distortion on the AC3 disc. But after the hour of comparing and after accounting for all the differences we came to the conclusion that both discs sounded good and quality wise both sounded basically the same. No clear winner or looser. AC3 did mess up on Nedry's voice but that could of been many things, but still this is enough for me to snub my nose at AC3 and choose DTS whenever I have a choice.

Both the DTS and AC3 versions had plenty of slam and sizzle. So don't let the magazines tell you DTS gives you more bass or better envelopment cause it don't. What we need are better tests. Dolby accused DTS of cheating with the improper sound levels. I don't care what happened just as long as it is fixed. We need both DTS and AC3 discs that are mixed and mastered at the same levels, with out this there can't be any definitive A/B tests.

But don't be fooled into think AC3 is just as good at DTS. Read my review of Delos's DVD Spectacular and what I say about the funky AC3 tone sweeps. Something bad is going on.

One important point of this Jurassic Park test was that AC3 does not sound terrible and that DTS doesn't blow AC3 out of the water. Before anything else is said about AC3 vs. DTS it is clear that more tests need to be done.

Who will win?
Dolby will, they have DVD, DSS, and HDTV all in the bag. But there might be space, a niche, for DTS in this market place.

What I see driving the market is software. DTS has accumulated a nice library of DTS 5.1 music CD's. This alone is reason enough to own DTS. Forget DVD's 2 channel 24bit 96kHz audio, it will never happen commercially from a software point of view and if it does it can't compete with the 5.1 channels of DTS. Having 3 front channels of audio really nice and it is something stereo can't touch. Will DTS be the ultimate multi channel music audio format? Maybe, and then maybe Sonys DSD or some other Japanese manufacturers plan of multi channel audio will become a reality, but I wouldn't count on it. Will DTS succeed in the DVD marketplace? They really have been waffling around for a long time, personally I think it might be too late, but in any case 5.1 music CD's are reason enough to get DTS.

Personally I think it is silly for anyone to buy a preamp/receiver that isn't both AC3 and DTS capable. Why would anyone want to take such a chance? It doesn't cost that much more.

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