I've always assumed stems must include effects. As you'd apply different levels of reverb to say a snare than a bass drum, so the stem would need this, as you couldn't apply it to a stem after

A little more info - "stems" were developed for film foreign markets.  Music, Dialog and later Effects, making it easy to dub in a new language and recut the film.  Otherwise you'd have to recreate the music along with the dialog, an expensive proposition.
 
Today stems mean whatever the mixer need.  A big classical project will probably mean the regular orchestra divisions - including for film mixers so they can duck the strings a bit if they are masking the dialogue, for example.  But for straight music it usually means busses.  Processed sometimes (tho that too depends - if the original mixer is in a pay dispute I would send the fewest artistic choices I could get away with).  That allows the re-mixer to remix without losing too much of the original work which someone has already paid for.  It is cheaper/easier than mixing from tracks.
 
If someone asks for stems, you'd better ask exactly what they want unless you've worked with them before and know.  And be paid in full.
 
@

I consider stems to be all buses that route directly to the master bus (assuming that there are no tracks bypassing them). Since upgrading to X3, I have started colour coding this set of buses.
 

Most musicians will probably want the stems separated from the seeds.
(sum juan had to say it) 

twaddle
I was just about to say that karyn
 
You may actually be right but I thought they would be the, 'unprocessed' audio.
 
I took the stems from an engineer who mixed my bands single last year and as far as I know there were no effects on them.
 
 
I think you're explanation is closer
 
Google Stems
 
 
Steve

Steve, just for the record, processed or unprocessed would both still be considered stems. I get stem mixes all the time from clients. For example, the client may love his mix but may be having a hard time with the bass. They'll send me the stems of the mix all mixed in wave format and they will already be processed just the way they want them. From there, I'll take the stems they send, and mix them while processing the bass. I ask them NOT to process the instrument they are having problems with so I can do it for them the right way.
 
Other times I get stems of the instruments unprocessed and I take care of all that. And for mastering, I may have a project where the client didn't raise the vocal track loud enough in the mix and they may not have time to do a remix. So they send me the mixed track plus plus the vocal track which is processed. I'll mix the vocal track in with the mixed track to raise the vocal a little more and the problem is solved.
 
Other times I'll literally get stems where 16 tracks of drums may end up 4 tracks of stems. Layered tracks of guitars may end up 2-4 stems, the same with vocals. It just allows us to manipulate projects faster with less tracks to work with. The downside is, you don't always have as much control as you want. Then again, you may not have a choice since the client may not have the time or the money to have you remix something. Most like to mix the stuff themselves....but when they fail, a stem mix and master can cost half of what the full blown mix/master might be.
 
So though stems may mean different things to people, they are just a sub mix of instruments that allow us to enhance things without recreating or fixing an entire mix. The thing about stems....they have to be in really good shape to attempt to salvage a project by using them. Garbage in, garbage out no matter if the stems are processed or unprocessed. ;) That's just MY take and personal experience though.
 
-Danny

Hey Danny, have you ever received something that was just a bit beyond being fixable and tried to do a McCartney and slipped in a guitar bit of your own? I always wonder if this happens.

backwoods
Hey Danny, have you ever received something that was just a bit beyond being fixable and tried to do a McCartney and slipped in a guitar bit of your own? I always wonder if this happens.

Haha, I have received some really bad performances as well as recorded some really bad.ones. On the things that are so bad they can't be fixed, I tell people the stuff is not quite ready because I'm not just doing this stuff for a paycheck.....I actually really care. But to answer your question, when I first opened my business, I wanted to.make sure nothing but quality came out of the studio.

In those days, everyone supposedly had a record deal pending and the quality/production really mattered on a project. And of course anything stamped with my name or my studio name had to "represent". I had this bassist playing for this band that was picky about nothing. He wasn't good enough to be picky nor did he know enough about good bass tone to act the way he acted. Long story short, his part was so bad, when he went home, I played the part.

When the band came the.next time, I played the tune for them with my bass and the bassist says "aren't you glad you listened to me? That bass works perfectly!" with the band chiming in saying "yeah it's great"! Though I felt good about that decision musically, it started to bother me. Right before they left the guitarist comes up to me and says "thank you so much for playing that part, your secret is safe with me". ;)

That's the only time I've ever done that though. There's been a few times where I've thought of it on a few net jobs that I've done, but I'd never do that again. All my net customers have been so incredible and receptive to me, i could just tell any one of them "you may want to consider re-cutting this part if you can". If they can, they always do. If they can't, we make the best of it. If it's super bad, I won't take the job on. And of course quite a few have hired me to play.bass, drums, keys, guitar or sing on their material as well. So we usually find that happy medium. :)

-Danny

Effects on stems can work, if you have the right effect and/or you are not sure if the next studio has that exact same software.  Again, that is something to double check w/ whomever is paying.  "Did you want that reverb on the vocal?"

Ditto... yup... I've always been under the impression that stems are individual tracks as well as buss mixes... basically it's a catch all phrase to say the same thing.
 
At least that's how I've seen it being used in the biz.

Danny Danzi

backwoods
Hey Danny, have you ever received something that was just a bit beyond being fixable and tried to do a McCartney and slipped in a guitar bit of your own? I always wonder if this happens.

Haha, I have received some really bad performances as well as recorded some really bad.ones. On the things that are so bad they can't be fixed, I tell people the stuff is not quite ready because I'm not just doing this stuff for a paycheck.....I actually really care. But to answer your question, when I first opened my business, I wanted to.make sure nothing but quality came out of the studio.

In those days, everyone supposedly had a record deal pending and the quality/production really mattered on a project. And of course anything stamped with my name or my studio name had to "represent". I had this bassist playing for this band that was picky about nothing. He wasn't good enough to be picky nor did he know enough about good bass tone to act the way he acted. Long story short, his part was so bad, when he went home, I played the part.

When the band came the.next time, I played the tune for them with my bass and the bassist says "aren't you glad you listened to me? That bass works perfectly!" with the band chiming in saying "yeah it's great"! Though I felt good about that decision musically, it started to bother me. Right before they left the guitarist comes up to me and says "thank you so much for playing that part, your secret is safe with me". ;)

That's the only time I've ever done that though. There's been a few times where I've thought of it on a few net jobs that I've done, but I'd never do that again. All my net customers have been so incredible and receptive to me, i could just tell any one of them "you may want to consider re-cutting this part if you can". If they can, they always do. If they can't, we make the best of it. If it's super bad, I won't take the job on. And of course quite a few have hired me to play.bass, drums, keys, guitar or sing on their material as well. So we usually find that happy medium. :)

-Danny

 
 Ha ! That's awesome Danny :) 
 
The part about sending stuff back to the source for improvement must actually be one of the hardest parts of your job. I can imagine some guys would be really devastated.
 

Guitarhacker
Ditto... yup... I've always been under the impression that stems are individual tracks as well as buss mixes... basically it's a catch all phrase to say the same thing.
 
At least that's how I've seen it being used in the biz.

That's what I thought too.