And I thought that SM always gave AAs on a FC...

I'm pretty sure you get a AA with 93% perfect. It doesn't even matter if the other 7% are all misses.

Combo is irrelevant to your letter grade.

Close but incorrect..you need 93% of total dance points..you calculate amount of dance points like this:
perfects x 2
greats x 1
goods x 0
boos x -4
miss x -8
and add those totals together.

If your total dance points is 93% to 99% of the max possible amount of dance points, you'll get a AA..if you get 100% it's a AAA.
And combo is totally irrelevant to scoring and grading..this is the way it should be IMO, but FFR relies very heavily on combo for scoring.

Actually, you're part correct on that... Grade is based off dance points, score is partially influenced by combo. You can get a higher grade and still get a lower score, depending on your combo. If all your misses/boos/goods are separated in a way to distrupt the combo, this isn't too hard to do. A friend of mine enjoyed trying to do it by getting a higher grade then me but a lower score to erase my higher scores

Because of bonus:
Stream: The ratio of your number of Perfects to getting all Perfects
Voltage: The ratio of your maximum combo to getting a Full Combo
Air: The ratio of your number of Perfects on all your jumps (R+L, R+D, etc) to getting all Perfects on all Jumps
Chaos: The ratio of your dance level compared to that of AAA (all Perfect) level
Freeze: The ratio of your total number of "OK"s on all the Freeze arrows to getting all "OK" on all the Freeze arrows

Voltage bonus added to your score will obviously change the score based on your combo.

Also, since the grading is HEAVILY based on the step's position in the song (what number step it is) depending on WHERE you miss your steps can drastically alter your score.

Yes, score has alot to do with that stuff. But grade is based totally off dance points.

And ultima, you forgot the +6 for every freeze arrow you get an OK on. Can't forget those...they can add ALOT of dance points if theres alot of freezes and you hit them all.

See? I said that already

Check aaroninjapan for scoring information throughout the different mixes. I didn't check the older mixes but all the newer ones use dance points exclusively to caluclate the score. Because this only relies on how many of each "quality" of step you hit (marvelous, perfect, great, good, boo, miss, and freezes) it's far simpler to calculate then the score, which uses step number as well as step "quality"

Chaos is the ratio of your number of Perfects on all the non-4th, non-8th arrows to getting all Perfects on all those arrows.

gg DtK

No offense, but something tells me that Aaron's information is more researched, and hence, more reliable. Unless you'd care to tell me how your information somehow trumps his?

The SM scoring does not go off of dance points as there is a "limit" to how many misses you can get without getting a AA.

...of course theres a limit. However many misses will drop your dance points below 93% Considering a miss takes like -10 from your dance score...it usually doesn't take that many to steal your AA.

i wish i could find out how to put songs on sm

Yep, also, because, I believe, boos and NGs also steal points away, they too can eliminate you from getting 93%, period. ^_^