I have now made my first comparison of the Polydor WBWB against the MCA WBWB.
General observation: The Polydor is a bit louder.
Some tracks are from the same digital master.
My Generation, Anyway, Anyhow, Anywhere: From the same digital master (but at different volumes).
The Kids Are Alright: Polydor has the full length version, and also sounds miles better than the shorter MCA mix.
Substitute: Polydor is mildly duophonic. (Only apparent with headphones). MCA version is pure mono and sounds better.
I'm a Boy: Unpleasant on Polydor, more distortion than on the MCA. Definitely the same mix, though.
Happy Jack, Pictures of Lily: As previously noted, only the MCA has the correct single mixes. Besides that, the Polydor versions sound "closer to the source".
I Can See for Miles: More clarity and punch on the Polydor. Compared to that, the MCA sounds like from a copy tape. Both versions have the complete first note (which is clipped or cross-faded on every other version that I am aware of.)
Who Are You: Couldn't hear a difference.
Won't Get Fooled Again: Polydor has the album version (sounding similar to the Who Collection), MCA has the single mix (sounding worse than The Singles).
Magic Bus: Polydor has the mono mix, MCA the stereo mix, but not with the complete intro as Meaty Beaty Big & Bouncy.
I Can't Explain: Couldn't hear a difference.
Baba O'Riley: The Polydor has the same fade-in as on The Who Collection and the old Polydor Sell Out CD. The MCA has narrower stereo image. Both are, of course, not even close to being the best versions on CD.
I didn't listen closely to the remaining tracks, I don't think there were big differences, and all those sound better on other CDs.
Interesting: I Can See For Miles has more stereo separation on the Polydor WBWB than on the MCA. On the Polydor, the bass is strictly in the left channel, on the MCA it is somewhat between left and center.
My Generation and Anyway Anyhow Anywhere are from the same digital masters on the Polydor and the MCA WBWB. They are at different volumes and different offsets, but I could optically match the two waveforms in both cases. Sorry for the misinformation earlier. (I edited my earlier post.) More info to come.
About Let's See Action, Join Together, Relay, Squeeze Box on The Who Collection: Phil Elliott has the same preferences as I have. They sound "uncompressed", in my opinion.
I don't really have an opinion about Who Are You single mix. I prefer the album version.
Repost from SH.tv:
Bringing this up again...interestingly enough, the US and UK CDs share the same digital transfer for quite a few tracks (12/19); it would appear digital transfers were sent from the UK, and then tweaks and replacements were made in the US. The mono tracks on the US CD aren't 100% identical in the left and right channels (they do *not* OOPS completely), but they are very close. In many cases, where the same transfers were used, the gaps between the tracks are identical, regardless of tweaking on the US CD.
Track by track:
1. My Generation *
2. Anyway, Anyhow, Anywhere *
3. The Kids Are Alright +
4. Substitute #
5. I'm A Boy *
6. Happy Jack +
7. Pictures of Lily +
8. I Can See For Miles *
9. Who Are You *
10. Won't Get Fooled Again +
11. Magic Bus +
12. I Can't Explain *
13. Pinball Wizard *
14. I'm Free *
15. See Me, Feel Me *
16. Squeeze Box *
17. Join Together *
18. You Better, You Bet *
19. Baba O'Riley #
* Same digital transfer on US/UK, US version tweaked (volume, EQ, bass centering, monoizing the mono tracks, etc)
+ Different mix/edit
# Same mix, different transfer
ICSFM, WAY, and Pinball Wizard all have bass centering on the US CD, similar to how LPs were cut.
@Andreas mentions elsewhere:
"Baba O'Riley: The Polydor has the same fade-in as on The Who Collection and the old Polydor Sell Out CD. The MCA has narrower stereo image. Both are, of course, not even close to being the best versions on CD."
He's correct about the UK version, but I disagree about the US. To me, it sounds like the US CD uses the master tape, just like the SH CD issues, but actually has slightly more pleasant EQ, which tames the upper midrange slightly. I don't hear any narrowing of the stereo image on the US CD. The transfer doesn't stay in sync with either the original Japanese Who's Next CD or the Canadian CD, so I'm guessing it's a unique transfer.
It's a mystery that a better transfer of I Can't Explain was not inserted for the US CD. And that the short version of TKAA was inserted.
I did the comparison because I was wondering where I'm A Boy came from on the US CD; as far as I know this was the first US issue of the stereo mix. I'm guessing the transfer (from the UK) was from the Backtrack 3 master, which is apparently also where the stereo mixes of Disguises and Run, Run, Run came from on 30 Years and the 1995 AQO CD, respectively.
What I didn't do was see if any of these tracks came from previous digital transfers. Perhaps another night.
At any rate, while some of the tracks marked * may be more pleasant on the US CD, the UK CD is actually a more raw source.
Oh, also, other than offset and indexes, the Japanese CD is identical to the UK.