The number of bars with drum samples in the average song can actually vary quite a bit. Usually, when determining bar length, one would look at the total run-time of the song and make calculations based on that. It can get complicated with certain loops, however.
One of the most common looping numbers of bars is four. This is usually enough to develop an indicative portion of a song, and then four bars can give groove, tempo and feel to a song, and so is great as a foundation or ’skeleton’ sample. The drum samples in the four bar loop can be organized as one total unique sample, with each bar being totally different from the last. However, most music producers in rap and RnB prefer to keep some element of comfort with the listener, and variance is the keyword. Varying drums from bar to bar using changes towards the end or velocity is much more effective at not inducing stress into your listener.
Sixteen bars is another common loop number, usually because in hip hop, 16 bars is a typical vocal verse length. So if you can develop the 16 bar loop, complete with pre-chorus introduction and an 8 bar switch-up (just an example), you can give a good example of the way the song would be structured. Using drum samples over these 16 bars will give see you test your creative limits, especially if you make a few beats every day. Introducing the hi-hats starting at bar 8, for instance, gives the song a great motion factor.
When considering changes to the music, you can easily look beyond drum samples and even instrument patches and notes. The more advanced composers will start some new harmonic progressions or expand the note selection in current form. If you change multiple things at once, this is a very powerful message to your listener that things are not at rest; movement is in the air!
If you really are serious about sequencing and arranging the next smash hit, think outside the box as well. Combine some methods, and utilize the vocals more, don’t just focus on the drum samples and instrument patches. Your singer could suddenly go from boring and predictable to wild and energetic in a matter of just a single bar. Keep your listener guessing ’til the end!
Drum samples are one of the easiest ways to introduce variance, as it requires no extra input on the vocalist’s part and can accentuate vocal parts and instruments without anything being different in those departments.
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