Although this does say 'Sampler Basics', it's not THAT basic, so if you don't know what a drumloop is, you should probably look elsewhere to first learn what sampling IS, and then come back here, to find out how to do it better. The way I will describe most actions in this article will be geared towards people using a sampler, such as the ESI-4000, or the Emu Emax 2, but the concepts will work equally well with a computer based sampler.

    One of the first hurdles you will encounter in using drumloops, is actually getting the drumloops. There are two ways you can go about getting samples: download or trade samples from someone who already made them, or make them yourself. Now with the former, you have the advantage of being able to just load up the sound, and get jammin; there are literally gigabytes of drumloops floating around on the internet, and available on sample CD's at your local music store. The quality of these sounds can run the spectrum, from some of the most poorly sampled, low bitrate, LP drumloops to studio, CD quality bitrate, custom drummers. If you choose to use premade loops, then just resign yourself to spending several hours (at least) sifting through tons of crap before you find that one gem; but believe me, that one gem can make all those hours of work well worth it.
    Now, for those of you who wish to have their fates not controlled by the whims of other sample-gods out there, then you have to realize a few basics:

.1.  Try to sample from the highest quality source you can.
It's easy to introduce noise if you so desire, while it's much more difficult to remove it.

.2.  Try to identify a part in the song where the beat plays by itself.
No bassline, no strings, no vocals. Sometimes having little clips of a fragment of a vocal or bassline part can be desirable, but until you fully understand what you're doing, I would recommend keeping it simple.

.3.  Look for beats outside the genre you write in.
You can sometimes find the most original and interesting drumloops from the most unlikely sources, like a Gospel album or 40 Funky Hits.

.4.  Check out CD singles.
One of the absolute best sources for good drumloops is from singles, which normally contain 3 to 6 remixes of a popular song. On a good single, there will be a good variety of beats.

.5.  Your local DJ is your best friend.
As with CD singles, the LP singles that your local DJ spins will have some remixes you won't be able to find anywhere else. You'll also get 'fresher' samples, since whatever he has in rotation is usually what's hot at the moment. But be warned! This is a double edged sword, since you can also end up with samples which sound 'played out'.

.6.  Just because it's stereo, doesn't mean you have to be.
I've found it to be fairly rare where I've preferred a stereo sample over a mono, most of the time stereo simply means copying the left channel to the right. While some drumloops can benefit greatly from being stereo (most notably being live), the bulk of your samples run just as well in mono as they would in stereo.

    Now it's time to turn that rhythm into something you can use. Sampling is very specific to whatever device you happen to be using, but here's a couple of tips to getting the most out of your new sample:

.1.  Lower sample rates can be your friend.
Depending on what sampler you use, you can get some great sound from lower sample rates. A good example of this was the old Emu Emax 1, an old 8bit sampler, which had a great filter. When you sampled something at a very low rate, you didn't get the tinny-cheap sound, you got this very rough interpretation of the loop; VERY COOL. When I bought an Emu Emax 2, which could load the Emax 1 samples, instead I sampled the Emax 1 playing the sound on the Emax 2. This way I got the great sound, which the Emax 2 lacked at low sample rates. This is VERY subjective, so play and decide for yourself.

.2.  Keep the loop as small as possible.
Try to limit your drumloops to one time through, since this smaller size will give you greater flexibility in composing later. If there is a breakdown or some variation on the 4th iteration of the loop, instead make two samples, one of the first loop, and one of the variation loop.

.3.  Always start the sample on the beat.
Most of today's advanced samplers allow you to start at a different offset than 0 in the sample, which gives you the ability to use one loop to create a patch that starts on the bassdrum, while another starts on the snare. It's usually much more difficult to do this with a sample that doesn't start on the beat.

.4.  Trim it as tightly as you can.
Whenever possible try to have the sample start as close to the first bassdrum hit as possible, and with no overlap at the end. A good way to do this is have the sample looping while you trim it. Try to trim as much as possible, but make sure not to disrupt the flow of the sample.

.5.  Experiment with chopping up a loop.
There are several programs that can do this for you, most notable being Recycle, which chops up a beat into its component parts (as best it can). This usually works marginally well, but when done correctly, you have all the pieces to make a cool rhythm that sounds like a loop.

    On most samplers these days, you first make a sample, and then you make a patch that describes how the sample is played; whether it's looped, it's ADSR, stereo positioning, etc. There are several methods that people use, and which work better in different situations.
    The most straight forward method is just to assign one sample to the entire keyboard, so C0-C8 (on an 8 octave keyboard) would all just be pitched versions of one sample. This method is easy (obviously) to setup, and doesn't limit the range of the sample in any way, but it does usually leave a large portion of the keyboard entirely unused. How often do you use a drumloop sampled at middle C (C4), at C1, or even C2? It's pretty uncommon to say the least.
    The most complicated and limited by far is to assign each drumloop to a key, and make sure that the tempo of each loop matches, then create a number of patches for different tempos. Now while this method does make doing stuff like Jungle or Drum&Bass exceptionally easy to improvise, I have found it to be incredibly limiting. Two of the most notable problems you will run into with this method is that all controller information affects all of the sounds, so if you want to pan 1 loop to the left, and one to the right, forget it.
    My personal favorite is just a slight variation on the first method. What I normally do is split the keyboard into 2 layers, C0-C4 and C4-C8. Then I create a separate patch for each drumloop. Not too terribly different from the first method, but later on in the article you'll see the advantage it yields.

    One of my biggest pet peeves is when I hear a cool song, and it's got a great drumloop, and it's just a tad off. Arrrggh! They were soo close and they just blew it! It isn't very common in commercially released music, but in the unsigned realms it's much more common than I would like. The sad part is, it's one of the easiest problems to fix! The problem usually happens when you're working on a song, you have a drumloop at 120BPM, and you're at 124BPM. The drumloop was sampled at C4, and D4 sounds about right; and with the rest of the track playing, it's hard to hear if it's on or off... WRONG! The rhythm is the driving part of the song, and you can't afford to have it off if you have any control over it. Here's the easiest way to fix this problem: Pitchbend.
    Yeah, Pitchbend, you know, that wheel on the side of the keyboard you almost never use... Well, it gives you the ability to dial that drumloop right in. I normally set up a drum track in the song with a constant 4/4 bass drum, then I create a 4 measure loop of the drumloop, making sure it loops because I SUSTAIN it, not because I retrigger it. This is VERY important! The key to tuning it is that you will hear the drift quite a bit more after it's looped at it's native rate 4 times and if you just let it go through once. The bassdrum track lets you hear how much it is off. Now, the Pitchbend has a range of -8192 to +8192, so it's time to tweak. At the start of the test drumloop, insert a wheel event, and set it to +1000. Does it sound better, or worse? If it sounds worse, try -1000; if it sounds better, try +2000. Once you have it within a block of 1000, drop down to 500, then down to 100. I almost never go smaller than that, since it's almost impossible for me to distinguish the difference. Remember, don't focus as much on the beat as the feel; does if feel like it's rushing, or dragging? If you do this simple trick I guarantee you'll have rocksolid drumloops (as long as you're sure the drumloop starts on the beat).

    One of the coolest things you can do with a drumloop is use more than one! The interplay between the two beats can really bring out some cool nuances you weren't aware of before, but there's a few things you should keep in mind before attempting this. First is that you will tend to have better results when you attempt this with fairly simple drumloops, ie, ones that are only a bassdrum, snare, and some hihats. The more complicated the drumloops become, the more likely you are to end up with something that sounds muddy or confusing. Also, you don't necessarily have to start the second drumloop at the same time as the first, experiment with starting it 120 ticks (assuming 480ppm) after the first beat, or 240 ticks. Another super cool effect is to have two beats that start at the same time, transform the two, but make sure when one is muted, the other is unmuted. And if you even want to push it further, add a controller fill for panning from 0 to 127 on the first beat, and 127 to 0 on the second for 8 measures. Try doing that with a drum machine; I think not.

    Another very common technique used in Drum&Bass or Breakbeat tracks is to simply retrigger the same drumloop 120 ticks or so after the initial trigger. You can also vary this a couple of ways, by either making sure the sustain doesn't allow the two to overlap, or better yet, allow them to overlap and hear them play off of each other. Now the reason for the patch with that same sample split across it becomes apparent. On many samplers, they will only allow you to play one note once, so you can't have two C4's playing at the same time. For this eventuality, you simply use the upper split for the primary drumloop, and the lower split for the secondary drumloop.

    That's it! I hope you found this article helpful in getting the most out of your sampler, and drumloops. If you have any comments or suggestions, or would like to share your tips and techniques with me, please feel free to contact me... Enjoy!