Our contenders for today are the new TPM R1 DVD and the Japanese TPM LD.

There are some hefty controversial debates among members of the HT community about the sound level and quality of this DVD. I haven't seen so wildly differing opinions about a title since the release of Jurassic Park on DVD.

The one thing that everyone seems to agree on, is that the DVD is recorded at quite a low overall volume level. Not only in comparison to the LD, but also to just about every other DVD. Some suggested that the reason is a that the DVD was recorded with a different DialNorm value. Others even assumed there is no DialNorm on LD, which is not true. Others suggested that the DVD was compromised in overall dynamic range, having a dull sound without punch and impact, at least in comparison to the LD, which was considered to have among if not the best soundtracks. Others complained about the dialog being difficult to understand.

Now the facts:

• The LD and DVD are both recorded with a DialNorm value of '-4', so the difference can't be attributed to that.
• But the DVD is indeed recorded several db lower than the LD, not through DialNorm, but simply through a lower overall recording level.
• The difference is 7-9db, more on that later. Remember that a difference in overall recording level can simply be compensated by raising the master volume by the same amount during playback.
• The perception of the dynamic range of a soundtrack is given through the ratio of the loudest effects (explosions etc.) relative to the average soundlevel (dialog etc.). This ratio is exactly the same, whether the DVD is recorded at the same level as the LD, 8db lower or even 16db lower. So there is no loss in impact or punch on the DVD, as we will see.
• Apart from the difference in overall volume, the mix on both is basically the same. While a lower recording level could also be called a different 'mix' already, it usually isn't. A different mix suggests that either the frequency response of the track is altered (roll-off of the ultra low sub 30hz bass for example, see JP DVDs), or the impact and design of single effects is changed (see beginning of T2 UE). Neither of which happened on TPM.
• The only 're-mix' that happened here, is that the level difference between the 2 versions is not constant (lets say 8db), but differs from one part of the movie to the other. The 'Podrace' for example is recorded 7db lower than on the LD, while the 'Invasion' and the 'Bigger Fish' scene in the beginning are recorded 9db lower. So Lucasfilm chose a different balance between the scenes. Whether the new balance on the DVD or the old on the LD is closer to the theatrical presentation is anyone's guess. But considering that the mix on the DVD was prepared by the same people that created this fabulous soundtrack in the first place, implies that the balance on the DVD is either correct or at least prefered by those involved.

So is the LD too loud or the DVD not loud enough? In my opinion, a little of both. The average difference between the 2 soundtracks is 8db. In comparison to other reference soundtracks, the LD is probably a bit hot, i would say by 1-2 db. That means the DVD is 6-7 below average. This is quite a considerable difference for sure. No wonder that those who simply put the disc in and listened at their usual personal reference level found the DVD to have less impact, unintelligible dialog etc.

I have no idea why they recorded it so low, as it doesn't have any advantages per se. But neither is it a big deal, its only a slight inconvenience that can be solved through raising the volume.

I would suggest two scenarios:

• If you want to enjoy this very dynamic soundtrack on its own, at its optimum level, listening to it 7 db louder than your usual personal reference level. Note that this does not put a bigger strain on your amplifiers and speakers!
• Listen to the LD 1db less loud than your usual personal reference level.
• If you want to compare the LD to the DVD, adjust the volume by 8db when you switch between them.

Lets have a look at the graphs now. Look at the main page for an explanation how these are obtained.

Note: 0db on the vertical scale of the graphs indicates 115db SPL, which is only achievable by the Lfe channel; all non-lfe channels max out at 105db, thus -10db on the scale

Description:

• Podrace Start, about 30secs, 7db difference adjusted for
• DD DVD 448kBit/s vs. DD LD 384kBit/s
• upper window is the left channel, lower window is the lfe channel
• red is DD LD, turquoise is DD DVD
• lfe data above 120hz is irrelevant!!!

Analysis:

• it doesn't get much more similar than this; the DVD has a 1-2 db lead in the LFE below 20hz, while LD has a slight 2db hump at 30hz. Small differences like these can most likely be attributed to either measurement accuracy or, if repeatable, difference in phase coherency due to the different bitrates used, which would make the DVD more accurate.
• its unlikely that the small differences are due to single or multiple effects being remixed. To reassure, I also measured several single effects with the same results.
• the frequency response of the LD track drops at about 18kHz, while the DVD keeps going until 20kHz. This is a limitation of the 384kBit/s bitrate of the LD, opposed to the 448kBit/s on the DVD.
• if you want to see how real differences among several mixes look like, check out Jurassic Park and Lost World

Description:

• Always a Bigger Fish, about 20 secs, 9db difference adjusted for
• DD DVD 448kBit/s vs. DD LD 384kBit/s
• upper window is the left channel, lower window is the lfe channel
• red is DD LD, turquoise is DD DVD
• lfe data above 120hz is irrelevant!!!

Analysis:

• Same comments as on the first graph, 18kHz dropoff, completely equal otherwise.
• Note that there is a 9db difference here instead of the 7db in the last scene, see the comments in my review above. So, if you adjust by 8db, some scenes like this one here will be 1db louder on the LD, while others like the Podrace will be 1db louder on the DVD.
• The fact that the LFE on the DVD is a bit higher above 80hz is irrelevant.
• The track on the LD clips at one point in this scene quite audible (the track actually clips, not the equipment), and i thought the lower recording level on the DVD might be able to prevent that, but it didn't. The DVD clips at the same spot. This is unfortunate, because it would have made the lower recording level actually useful :O) The reason for the clipping has to be in an earlier stage of the mastering.

Description:

• 'TPM' Podrace vs. 'Titan AE' Earth Explosion
• upper window is the left channel, lower window is the lfe channel
• red is Titan AE, turquoise is TPM

Analysis:

• Is TPM a loud soundtrack with exceptional bass extension? Yes.
• Is it a sensational mix? Yes.
• Is the bass in Titan AE even louder/deeper? Yes, considerably, especially in the main channels.
• Does that mean that Titan AE is a better soundtrack? No, not at all. Both are excellent. The bass is ungodly on TPM already, but Titan is even a bit beafier. On the other hand, I find the overall sound effect editing, soundstage, imaging, bass transparency and coherency of TPM superior. Both are definitely in the top 5 of all time.
• If pure bass level and extension is your major concern, then TPM i slightly behind 'Titan', 'U571 DTS', 'Toy Story 2' and 'The Haunting DTS'.
• FYI, the often touted 'Gladiator DTS' or 'Jurassic Park' (even the LD or repressed DTS DVD) are far behind all of the aforementioned.

One of the finest soundtracks ever produced is finally on DVD. For some reason it was recorded at an unusual low level. If you know how to compensate for this (by raising the overall volume) this has no negative effect on the soundtrack, as has been shown on the graphs above. So its only a slight inconvenience.

The facts presented above show that both soundtracks measure completely alike after adjusting the volume. That means that claims like 'more impact' and 'more punch' in favor of either the DVD or the LD are not accurate, maybe a placebo effect of one's favor of one format over the other. As mentioned, if the volume is adjusted by 8db between the 2, some scenes will be 1db louder on the DVD, others will be equal, and still others will be 1db louder on the LD. Overall a tie.

Now, that is the objective part, but there is of course also a subjective part, that can't be measured. Which raises the question, which track i prefered personally.

I prefer the DVD. Why?

• IMHO, the DVD is smoother, yet not less detailed. The LD is slightly harsh by comparison. Listening to both at reference level, the DVD causes less fatigue.
• Usually i don't buy into the bitrate hype in both DD and DTS. I am impressed through quality, not numbers. 2 of my personal favorite soundtracks: Toy Story 2 (DD) and Saving Private Ryan (DTS) are at the corresponding lower bitrates of the corresponding codecs. I have seen as many high bitrate soundtracks that sucked, as i have seen low bitrate tracks that rocked, so bitrate can't have more than a marginal difference at best. Basically the only soundtrack where i always thought that a higher bitrate might actually help a bit, is TPM. The Podrace in particular. There is so much going on there, effects comming from every direction, that i always felt that the soundstage and the imaging was at the borderline of colapsing, loosing pinpoint control over the multitude of effects. And indeed, i found there is much more coherency and better imaging control at the loudest parts of the spectacular race on the DVD. Whether this is indeed due to the higher bitrate, though, is not clear, of course.
• The bass on the DVD seems slightly tighter.

Feel free to have different personal preferences on these latter subjective issues, but please stop accusing the DVD of having 'less impact' or 'less dynamic range'. That simply isn't true, or at least the opposite is true as well in other scenes, if indeed someone is picking up that 1db difference, which is highly unlikely (3-4db yes, 1db no).

On the issue of dialog intelligibility. This is a very dynamic soundtrack, on both the LD and DVD. That means that special effects are recorded a lot louder than average sound effects and dialog. Soundtracks like these sound incredible on highend audio systems that allow listening at or slightly below reference levels without clipping or compression. On average systems, the problem arrises that you might turn down the volume a fair bit when the tremendously dynamic effects kick in, because either your system is too strained or you don't want to wake your neighbors/family. After the effect attack is over, normal sound cues and dialog are now far too low in volume, being unintelligible at times, so you need to turn the volume back up again. This is not a sign of a bad soundtrack, au contraire, a sensational dynamic uncompressed soundtrack is bound to show this characteristic on every but the very best systems. There are 2 possibilities. Either you get a better system (or new neighbors) or you engage the dynamic range compression on your DD receiver/prepro which limits the enormous difference between effects and dialog to the level of a normal less dynamic soundtrack.

The general procedure would be this. If you want to listen to a movie with a limitation in maximum volume that can't be surpassed (wife asleep, neighbors, system stress), raise the overall volume to the point that dialog is clearly intelligible or loud enough for you liking. If the loudest effects and explosions are too loud now or sound stressed on your system, start raising the DD compression from 'none' to 'low' or higher, until the loudest effects aren't overbearing. Don't be ashamed to use it, DD compression (or midnight mode) can really be a great and useful feature. Playing remote jockey while looking a movie sounds worse, is more stressful and distracts from the presentation. With DD compresion, the receiver is basically playing jockey for you in realtime, with pre-programmed meta cues, better than you could ever do it.

Some suggested that you have to raise the center channel volume on this track to make the dialog better understandable. This is actually the worst possibility to compensate for the shortcomming of your system, but you can do whatever you please. But i wouldn't recommend to do this in any situation.

And please don't use the THX Optimode on the DVD. Calibrate your system with AVIA or VE and be done with it! If you get vastly different results using the THX Optimode tools on the discs, that only means that a) the THX tools are wrong, which happened on some discs before or b) your room has nasty frequency response characteristics (most have) which get revealed because the calibration noise on the disc uses a different frequency band than AVIA or VE.

Best regards
Bjoern Roy

Note: you can find my picture analysis of the TPM DVD here .