I just got my dvd of the Japanese version. Very interesting.
It goes without saying that the orig. language print allows the performances by the Japanese cast members to REALLY shine through.
And the Japanese voice they used to dub Russ Tamblyn works pretty well, much better than the English voices used to dub Japanese actors.
In fact, Russ Tamblyn's dubbed voice makes him a little more tolerable.

(No more teddy bear and SPCA jokes.

)
And Kumi Mizuno? What can I say, other than
the First Lady of Kaiju. A total class act.
And yup...ALL the references to Frankenstein are there. As well as the Characters referring to each monster by their names (Sanda and Gaira)...
That airport scene...even though, in the Japanese print, we DON'T see the poor woman's clothes getting spat out

, something I noticed on the sound mix that seemed to be missing from the American dub...her screams are MUCH more pronounced, in the American mix they are nonexistant with all the other noise and music going on.
That alone brings it back to a pretty disturbing level.
After years and years of watching the American print, it's interesting to take note of Ifukube's full score, compared to the stock library music that we are used to.
As much as I love Ifukube, it's still going to take some getting used to. Overall effect, the music seems too slow and repetitive in parts. But, it's the real deal.
But, also...for all the stateside releases of Toho flicks, it becomes clear that this was one where they spent some time doing the best they could. I just recently saw Godzilla vs. King Ghidorah in its dubbed version and was mortified.
Oh... a couple extras show some special fx outtakes, mostly miniature vehicles. It was fun watching a maser cannon rear-end another!

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