The audio from the Laserdiscs would be nice since it’d be a far greater bitrate compared to what’s on BD. Which is bullshit lossy instead of lossless.
It is always nice to archive LD’s. Even when much better quality is available, the comparison is invaluable. The Star Wars LD archived versions have been priceless even though the quality is hit or miss.
One thing to consider when comparing quality is not just what the bitrate is. The bitrate of a modern recording could be lower, and yet have far superior audio quality and clarity. Especially when talking about older audio. And for the old LD’s you have to determine which audio track the audio is stored in. If it is stored in the digital track, it is of modern quality (CD quality stereo audio). If it is in the analog track, it is no better than VHS or broadcast TV. So if these Star Trek LD’s have digital audio, they are indeed a higher quality recording. If the audio is in the analog track, the chances of it being better than a modern compressed audio stream is non-existent. And that doesn’t even get to the question of how good the recording is in the first place. And on top of that you have to know how good the source material is and how good the transfer was.
For instance, we have the different Star Wars audio tracks form different LD sources. The original 1977 dolby stereo (matrix surround encoded) is available on the older discs, but it is much inferior to later releases. Cleaned up audio from the film prints might actually be better. But the 1985 and 1993 audio mixes are available in the digital track and are far superior.
So the question for the Star Trek LD’s is what is the original source for the transfer? Is it the same prints used for the BR transfer? Or is there a generation difference? Was any clean up done to the audio? Any noise reduction or hiss removal? It is in the digital track or the analog track. To be higher quality than the compressed BR mono track it has to be from the same source, using a good transfer device, and stored in the digital track on the LD. Otherwise, even though it is compressed, the audio on the BR is going to be higher quality. Remember, it is mono stored in a stereo track. That can be compressed at 4:1 without any loss in quality (stereo can be compressed at 2:1 without any loss in quality). That is just the nature of audio recordings and data storage.
And the other question is did they do too much clean up to the BR audio? Too much clean up can damage the audio and remove intended sounds rather than just removing age and duplication related artifacts.
But to do any of these comparisons, we need a archive of the LD’s. This has been invaluable for Star Wars and it would be for TOS as well.