Being a slightly picky person when it comes to music tag metadata in my files, I haven’t found a great way to original release year OR recorded year for a compilation or non-standard album. For instance, I got a Sufer Rosa/Come On Pilgrim combo disc and it was fairly easy to figure out the original release year for each album. It would be virtually pointless to tag the year the hybrid disc was produced. It’s the MUSIC that I care about, not the manufacturing of the reissue or remastered edition. Even albums with bonus material should be tagged with first release in mind. The actual bonus material is up to debate whether or not to tag it when it finally gets released or the same period of recording.

There are three potential dates: date written, date recorded, date product is made. I personally like recorded date for historical relevance.

While allmusic.com is a great resource and will usually tell you the year a song appears on the original album, reliability falls apart once we precede the album era or unreleased songs. Take Woody Guthrie… He’s got a Dust Bowl Ballads album recorded in 1940 for a 3-78rpm set. In later was reissued on Buddha in 1964. This is easy enough to describe as 1940. Although I’ve heard and check this out from the library, I don’t own this. I recently caught The Ultimate Collection double-disc of 51 songs from Prism Leisure for a mere $1 (I’m not saying where I found this; it was the last one at that price anyhow)! While this is a real deal thanks to Euro-lack-of-copyright, there isn’t much documentation other than faulty liner notes and mention of companions who play on some of the individual tracks (Sonny Terry and Cisco Houston). Not even a hint of what year each song came out, [Sheesh]. I can guess from my knowledge of Guthrie that the songs range from 1940 to 1947 and possibly later. I can assume all Dust Bowl Ballads tunes are from the same session in 1940.

If you’re lucky, iTunes will accurately yearify a compilation by main date per song. I was and am out of luck with this one. Usually if I don’t have immense interest in exact year I’ll leave it blank, but I do like to use year for playlist and sorting purposes sometimes. In cases like this, I’ll guess and overestimate. So I’ll place the Dusty songs at 1940, and if I’m ambitious I’ll search each song I’m unsure of. As I don’t want to waste a couple hours on 51 songs, I’ll put 1947 on those I’m clueless of. I did start a inch of research that “This Land is Your Land” was penned in 1940, but recorded in 1944.

Further findings:
– What others think should be used for the year id3tag

and…

I particularly make an effort on any tracks going into the Core collection to make sure their year is correct. For studio albums, it’s easy but it’s a pain for Greatest Hits albums.

I have not found an automated way of fixing the year yet. Let me know if you find one!
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I can’t believe there is no easy way around this. I’m not the only one.