- When we see the snowspeeders taking off (after the scene of R2, "Imperial walkers on the north ridge"), there is no music.
- When R2 is being loaded into Luke's X-Wing, C-3PO's "And" is more clearly heard before saying "do take good care of yourself."
- Yoda makes a frightened "Ehhhhh!" just before Luke says "Like we're being watched" and points his blaster at him.
- In the asteroid field, after C-3PO says, "Oh, this is suicide", he says, "There's nowhere to go."
- In the Yoda training scene, Yoda is clearly heard saying "Yes..." before "run".
- "Anger, fear agression...the dark side of the force are they. Easily they flow... quick to join you in a fight...." is mixed much louder.
- Yoda: "Consume you it will... as it did Obi-Wan's apprentice." It seems a different, less aggressive take of "as it did Obi-Wan's apprentice" is used.
- Right after Luke's failure in the cave, the establishing shot of the fleet features the classic TIE sound effects from "Star Wars" just like in the 70mm cut.
- The droid's "Eh chuta" seems to be a different take.
- C3PO only says "Hello?" once when he thinks he hears an R2 unit and the voice of the unseen guy who blasts him is different.
- Added Chewbacca vocalization heard over the shot when Boba Fett makes his entrance after Vader's "We would be honored if you would join us."
- Han screaming when he is getting interrogated is much louder in certain spots during the Vader and Lando conversation.
- C3PO has an additional line at the very beginning of the carbon freezing scene. "Oh dear, what now? I don't like the look of this."
- When Luke forces Vader off the ledge in the carbon-freezing chamber, his grunt from earlier in the battle is reused instead of his "Ahhh."
Some additional notes from various posts on this forum:
*Right after Luke puts the charge into the AT-AT and blows it up, the very next speeder Veers' AT-AT shoots down has an airplane sound effect in the 35mm which is mixed much, much softer in the mono.
*Music is generally mixed much more prominently, with much punchier brass and violins. For a good example see the Hoth base scene right after the power generator is blown up. The music is inaudible in the 35mm and only fades in when 3PO appears- the missing music is not only audible, but very prominent in the mono. For instance, in that very same scene, right before Leia falls down, she screams twice in the mono mix. No extra explosion before she falls. And as C3PO is climbing up the ramp, the most prominent sound in the mono mix is the flutes and the swooping strings. In the 35mm, it's C3PO footsteps on the ramp, and the ramp sound effect- only to have to dial the music back up for the next scene (Vader).
*The shot after the Falcon escapes Hoth, the X-wing flyover is not nearly as prominent.
*The asteroid field sequence- all the sound effects are drastically muted and some are entirely missing. Focus is on the music.
*There is much louder computer sound effects in the scene right before the big Han/Leia kiss on the ship.
*Right after Leia screams seeing the Mynock out the window... audio of her footsteps on-set is much more prominent.
Many of these later reappeared in the Special Edition.