DVD

France Carlotta Blu-ray has best encoding of France/Hong Kong/Japan. Criterion/BFI are older master

(Raro/Madman/Shochiku DVDs probably similar)

Criterion 4K Blu-ray, caps

As with other Kurosawa 4K's, Criterion has a less processed master than Toho and BFI.

Criterion NTSC DVD overall. The 4K restoration's track is denoised and sounds muffled, but has a few of moments where it edges out in detail

Audio analysis between the Criterion 4K Blu-ray, BFI Blu-ray and Toho 4K Blu-ray

The mono on the Criterion is severely filtered resulting in it sounding incredibly muffled. It is nearly as filtered as the 2003 original Universal DVD which had extreme filtering and sounds horribly thin. The 2008 DVD remaster and original LaserDisc analog mastering are mostly left alone. The original LD master is from a worn element but otherwise sounds very natural. The 2008 DVD is the highest quality version we have without the heavy filtering and the defects of the LD master. It isn't perfect but easily the best of the main four sources by a dramatic margin. 

The existing 4K SDR restoration looks excellent, but the Criterion extras are limited and disappointing. The classic Stewart interview commentary from the LD is ported over but given a new mastering. Compared to past releases it has been very slightly noise reduced.

Fox Blu-ray better encode than Criterion Blu-ray

2003 Fox DVD slightly better

Japan IVC Blu-ray but not English-friendly

Film Foundation has 4k restoration https://www.film-foundation.org/world-cinema but no EN-friendly release yet

BFI Blu-ray > 2018 Boxset Criterion (slightly). 2012 Standalone Criterion significantly worse.