[british beef]

i need help. what is the general theory behind a basic drum fill.

[TomAwesome]

It's just supposed to be an interesting little transition into the next part of the song. They'll pretty commonly incorporate a tom roll or something. Just listen to music you like, and pay more attention to the drums.

[Thixotrope]

I would start by making friends with a drummer. Growing up, I had one guitar player friend and about 5 drummer friends. Now most of them didn't care about showing me the drums but I watched them intently. I listened to the fills they played, where they played, how they played them, the sticking they used, what cymbals and drums they hit and where. etc. When a song changes feel, watch the drummer. If you can't watch a drummer, listen to one.

A good *starting point* is Metallica's ...And justice for all album It doesn't matter if you like Metallica or if think thinks Lars sucks or whatever but the point is to listen to each fill he does. You have to vicariously play the drums for the music you're writing. You'll be able to tell right off the bat if a fill you write fits the songs and links each part into a cohesive whole or is too blatant, lacks energy, or is too contrived. If its a metal song you'll probably end up programming a flurry of sixteeth note triplets on the snare and toms. If you're writing country, a fill could be as simple as syncopating the snare or bass drum at the end of the phrase.

Short answer, listen to your favorite drummers and get an idea of what you like or don't like, see how it can inspire you to write your own drum parts. Notice I didn't say COPY drum fills. In the same way that what you write on the guitar or piano is a melting pot of your influences and life experiences let drummer be the same thing.

I hope this helped or at least put you in the right direction.

[Leec]

Whilst that's good advice, if he doesn't have much of a clue about drums, it might be a baffling knowing where to begin.

A simple rule you can apply is something like Mike Portnoy's 'bag of tricks':
Take a bar and divide it in 16ths. Break the bar up around the kit, hitting something on every 16th note.
Start with a simple pattern like 2 snare hits, then 2 kicks, then 2 high toms, then 2 kicks, then 2 mid toms, then 2 kicks, then 2 low toms, then 2 kicks.
Try mixing the orchestration up. Try swapping a 2 16ths for 3 16th triplets. Try leaving a beat or two out.

You could also adopt a simple rule of thumb for the pace of each fill. If your fastest riff features 8th notes, use 8th notes or 8th note triplets for the fill. If the fastest riff uses 16ths, use 16ths for the fill.
This will stop you losing too much pace at the turnaround.

Neither of these are conclusive in anyway, but they should be ok as basic starting points.

[TonyFlyingSquirrel]

Originally Posted by Leec

Whilst that's good advice, if he doesn't have much of a clue about drums, it might be a baffling knowing where to begin.

A simple rule you can apply is something like Mike Portnoy's 'bag of tricks':
Take a bar and divide it in 16ths. Break the bar up around the kit, hitting something on every 16th note.
Start with a simple pattern like 2 snare hits, then 2 kicks, then 2 high toms, then 2 kicks, then 2 mid toms, then 2 kicks, then 2 low toms, then 2 kicks.
Try mixing the orchestration up. Try swapping a 2 16ths for 3 16th triplets. Try leaving a beat or two out.

You could also adopt a simple rule of thumb for the pace of each fill. If your fastest riff features 8th notes, use 8th notes or 8th note triplets for the fill. If the fastest riff uses 16ths, use 16ths for the fill.
This will stop you losing too much pace at the turnaround.

Neither of these are conclusive in anyway, but they should be ok as basic starting points.

I concur, syncopation with feeling is key here. They work in relationship with each other to transition from one sentiment to another, ie: verse to chorus, etc...

[jacksonplayer]

I tend to divide my fills into those based around the kick and snare and those based around toms. They're not mutually exclusive, of course.

Also, for major sectional divisions, I like to do fills that take up most or all of a bar, whereas secondary divisions (between verses, etc.) I either just give a one- or two-beat fill at the end of a bar or even just a single crash cymbal at the beginning of the next bar.

I would say, to start, keep it simple and do a couple of tasteful fills, rather than going for the "full Portnoy."