Song order is generally determined by the artist, producer and record label. Or some combination of the three.

While it’s true that the artist, producer and label usually have strong input on song order, I do get asked for input on some sessions. For me, an album should have some kind of logical emotion flow to it (think movie, with beginning, middle and end). Unless you’re going for a drooling schizophrenic listener, you probably don’t want to alternate fast, slow, fast, slow, etc. Many artist like to start upbeat, capture the listeners attention, then give them the mellow or slow pieces and end the record strong. Song order and spacing between songs can have a powerful impact on how the listener FEELS while experiencing your music.

I agree! Flow is everything. Usually come out of the box on song one with an attention getter.

Have you ever noticed track 6 is usually the best song on the album?

They call track 6 the "reaffirm" track where the album basically starts over, many times it is the hit often times, the best song.

Go through your CD's and see what the percentage of CD you have that have a good track 6.

When I was in the industry, I heard this from several producers. You also want to end the album with the listeners "wanting more"

I guess that's sort of like having the first track on Side B being an especially strong one for LP.

For vinyl, I'd like to see a slightly softer tune at the end of each side. That enables me to "save space" at the end of the side to get all the aggressive songs at the top of the side at maximum level. Also, it minimizes inner groove distortion as the side diameter decreases.

Flow is always important, not only in the actual song sequence, but also in the spacing between tracks throughout. One track should lead to the next in a pleasing fashion.