Before hip-hop hit the big time, it was a very underground phenomenon and as a result, most of the artists at the time had to make music as cheaply as possible. Indeed, some bands couldn't even afford a drum machine, so "beatboxing" was born where a performer would imitate the sounds of a drum kit with his mouth to create the beat for the rapper to do his thing over. While it seems kind of hokey now, your own voice is actually still quite a decent source for new drum and percussion sounds. Here are some tips on getting the best results from your vocal drum sample experiments:
• Just Let Loose
I recommend setting up your DAW to record and just record a whole bunch of random sounds at once. Try imitating the sounds of different drums with your voice. Alternately, try making percussive sounds that aren't imitating anything... a cough, a wheeze, a burp, a sharp inhale or exhale, etc. Just improvise and don't give it too much thought. Once you feel you've had enough, import the file into your favorite audio editor and separate the good stuff from the bad stuff. These are just your raw sounds. You're going to want to...
• Use Effects to Sculpt Your Sounds
When I got my first sampler (an Ensoniq Mirage rack), I was disappointed by the fact that when I tried to make vocal drum samples, they didn't sound as awesome as when Yello did it. The reason, of course, aside from the fact that Yello are godlike, is that their samples had been processed more than cheese in a can. Definitely take the time to experiment with compression, EQ, reverbs, filters, and other effects that may help you bring your sounds closer to the sounds you're trying to imitate. Use compression to exaggerate the attack and bring out the snap in your sounds. Use EQ to thin out cymbal sounds with a highpass filter, or exaggerate the low end frequencies in your kicks. Once you've processed your sounds into oblivion, resample them with the effects and build your kit.
• Use the Mic to Your Advantage
Microphones are subject to a phenomena known as "the proximity effect" where bass frequencies get exaggerated as the subject gets very close to the mic. You've probably heard comedians on TV use this trick to imitate the sound of explosions or the voice of God. All you need to do is get yourself unnaturally close to the mic and the proximity effect takes care of the rest. Most mics are also very sensitive to plosives, or the popping vocal sounds like the letters P or B make that are produced with a percussive burst of air. If you don't use a pop filter or get too close to the mic, these get exaggerated and result in pops. Don't be afraid to sample some of those to act as the start to new percussion sounds with a little sound design.
• Stretch and Pitch
By no means should you feel you need to use your samples "as is". Take advantage of your sampler's abilities to re-pitch sounds or use time-stretching and granular processing to alter their length and character. Pitching sounds up past their root key is an easy way of adding a little punch to your sounds. Try playing the sounds backwards, too.
You'll get much better results if you break up the sound you're trying to imitate into components. So if you're imitating a snare drum, use one sample to imitate the resonance of the drum shell, one to imitate the crack of the impact, and one to imitate the rattle or buzz of the snare. Process them separately until you're happy, then use a bus to compress the individual layers together and resample!