AC3 Mixes of Laserdiscs do Not Contain True Theatrical Masterings

[Sambarker04]

I have the US LaserDisc of Bean The Movie and the LD AC3 mix is way different than the R1 DVD mix. Firstly, there was heavy compression throughout and the rear channels have been screwed up. On the left rear channel, it was either the mono rear or one of the rear channels, and on the right rear channel, it was a duplicate of the LFE channel. The LD mix also includes the final seconds of the post-credits scene where we hear Mr. Bean’s footsteps fading out that was cut on the DVD mix. I haven’t analysed the two yet, so I don’t know if this LD mix was done to be near-field or not.

[zoidberg]

The same goes for other AC3 5.1 laserdisc film mixes, which have serious limitations on their dynamic range and gain levels. I analyzed most of them.

An incredible claim. There are so many laserdiscs with AC-3 (over 1100 according to the lddb).

Could you share with us some more examples?

[stwd4nder2]

This only holds true if you have compared to the CDS track decoded from a print.

There's no getting around this. If you're not directly comparing it against the actual theatrical audio your point is pure speculation.

[dvdmike]

I imagine this sort of comparison would be interesting to make with something that had a Cinema DTS mix to compare to, since captures of those seem to float around depending on the title.

That way, you can properly cross-reference it with something you can confirm is theatrical and untampered (barring semi-standardized channel attenuation) and would be in an age where digital sound mixes started taking hold.

Unfortunately, Terminator 2 is kind of a rubbish example since we have no idea how the CDS mix was handled and I believe I've heard once or twice that the LD AC3 was stemming from the 70mm 6-track mix rather than the CDS mix (as I believe the two were handled differently to account for format capabilities; not to mention the former being analog).

Sticking to Cameron, True Lies or Titanic might be a better tests for this if you can get your hands on the right assets. Granted, I never did any research on what sound elements were used for those LDs, but given Cinema DTS mixes were more standard by the time those came out, odds are they may have just ported those mixes.

Also, whilst not at all implying you made any error in your audio measuring process, make sure the AC3s have the dialnorm stripped out. Once in a while I forget about that being a factor, so nowadays I just try and automatically convert my AC3s with it auto-removed with FFMPEG as part of a preset BAT file I have around.

Agreed, true lies would be by far the better comparison

[Kado_2020]

I imagine this sort of comparison would be interesting to make with something that had a Cinema DTS mix to compare to, since captures of those seem to float around depending on the title.

That way, you can properly cross-reference it with something you can confirm is theatrical and untampered (barring semi-standardized channel attenuation) and would be in an age where digital sound mixes started taking hold.

Unfortunately, Terminator 2 is kind of a rubbish example since we have no idea how the CDS mix was handled and I believe I've heard once or twice that the LD AC3 was stemming from the 70mm 6-track mix rather than the CDS mix (as I believe the two were handled differently to account for format capabilities; not to mention the former being analog).

Sticking to Cameron, True Lies or Titanic might be a better tests for this if you can get your hands on the right assets. Granted, I never did any research on what sound elements were used for those LDs, but given Cinema DTS mixes were more standard by the time those came out, odds are they may have just ported those mixes.

Also, whilst not at all implying you made any error in your audio measuring process, make sure the AC3s have the dialnorm stripped out. Once in a while I forget about that being a factor, so nowadays I just try and automatically convert my AC3s with it auto-removed with FFMPEG as part of a preset BAT file I have around.

Agreed, true lies would be by far the better comparison

I have about 25 cinema DTS mixes on hand, including True Lies and Jurassic Park. I will check them when I find the time.

[zoidberg]

Use this thread, which you created especially, instead of junking up the T2 CDS thread please

[david49120]

My personal advice : Just because software provides an analysis doesn't mean it differs from listening. However, if all this holds true, it would allow us to compare future Blu-ray releases to see if they match the theatrical mix.

I listened some ac3 LD tracks like Twister, this soundtrack is more powerfull than cinema dts or same. 

I read on the French projectionists' forum that someone mentioned this : "There are different mixes, sometimes not as good as the Blu-rays (in my opinion), sometimes identical. Bear in mind that the theatrical mix doesn't have the same dynamic range as the Blu-ray."

[dvdmike]

My personal advice : Just because software provides an analysis doesn't mean it differs from listening. However, if all this holds true, it would allow us to compare future Blu-ray releases to see if they match the theatrical mix.

I listened some ac3 LD tracks like Twister, this soundtrack is more powerfull than cinema dts or same. 

I read on the French projectionists' forum that someone mentioned this : "There are different mixes, sometimes not as good as the Blu-rays (in my opinion), sometimes identical. Bear in mind that the theatrical mix doesn't have the same dynamic range as the Blu-ray."

The DS track on Twister prints was way harder in my opinion