Following on from the previous article on emulating bass, this article is about emulating drums and mainly about emulating drummers.
I'm of two minds when I emulate drums. I'm either:
The first aim involves working with compromises. Ideally, I'd be better off recording a good drummer playing an acoustic kit in a nice-sounding room with great mics, preamps, etc. That's not always possible. And the aim maybe to have something ready very quickly, so I turn to emulating a drummer.
The second aim is more useful for generating percussive elements that fit tonally into the music but with a different impact to that which I could achieve with a normal drum-kit. I'll discuss those in a separate article.
In this article, I'll stick with (1) achieving a realistic drum sound.
Loops
My short piece of advice is to use drum loops. Use some decent quality loops with sufficient rhythm variation and inherent tonal consistency and many would be hard pressed to tell the difference between a drummer and a loop. If they can tell the difference, it's either a bad set of loops or user error, e.g. you've used the same loop too often in the song. After, how could they tell the difference since it would have been a real drummer who recorded the loop in the first place.
Midi
The long answer is for when you don't have any suitable loops, including if you don't have any loops. Then you'll probably be resorting to midi to trigger drum sounds in a sampler. There are some tricks to make it sound more realistic.
Play like a drummer
Drummers have a maximum of four limbs. That's an immediate restriction of 4 items being hit at any one time. Can be more than 4 note polyphony though due to layering and the release of certain instruments (e.g. cymbals). Actually the right hand can hit the rim and the head of the snare together, but that's a bit of an exception.
That's the first restriction. If you want it to sound like a drummer, then limit it to four hits at a time.
Layout
Also look at the layout of a traditional drumkit. For a right-handed drummer, the right-hand usually crosses the body and plays the hi-hat, while the left-hand plays the snare. Either hand is used for the toms and cymbals. And either hand can add to the other hand to double up on the snare or hi-hat. Different styles call for different arrangements. That's the traditional pop/rock layout and handling.
Watch the combinations
The short closed hi-hat sound is formed by the right-hand hitting the hihat while the left-foot holds the hi-hat closed. If the right-hand is hitting the snare, toms or cymbals, you can't get a closed hihat sound. If would be the gated half-open sound caused by the left foot lifting the top hi-hat and then pulling it down. It's a weaker sound than closed hi-hat. A rock drummer may have a much more ringing open hit-hat sound, especially for keeping up with doubletime kick and snare patterns.
Would a drummer alternate?
If the pattern relies on 16th beats on the hi-hat, then the drummer would most likely alternate hits between the right and the left hand. I know of four ways to implement this:
It also applies for other drums as well, not just the hi-hat.
The Machine Gun
The bane of a lot of 1980s pop was the electronic snare that sounded the same no matter how hard you hit it. Hit it in a quick repetition and it sounded like a machine gun. There was just no flexibility. Drum synthesizers and samplers have come on a long way since then, but unfortunately some interfaces do not make it obvious to avoid. It's not specific to snares either; hi-hats, toms, anything hit rapidly and repeatedly risks introducing this effect.
Similar to the methods for alternating the hands, I can think of 4 ways of implementing this:
Ghost Notes
What makes a real drummer more interesting than a basic drum pattern is the presence of ghost notes. This is where the drummer would lightly hit a drum, e.g. the snare, but not as a focus of the rhythm. Often these pre-empt the main snare hit, almost leading into it. The ghost note would be short and lower in volume than the main hits. The ghost notes don't just have to pre-empt the main hits, a drummer will include them in to vary up the patterns and to add spice to the rhythm. If they're occurring in the same place in every beat, then they're probably not ghost notes but an integral part of the pattern. I've always seen ghost notes as being variable throughout a song. Due to the varying lower volume, if you're not listening carefully, some ghost notes would end up being imperceptible.
Try listening to a jazz drummer, especially if they're playing a simple blues rhythm. You'll notice the ghost notes more when the rhythm is simpler.
Accuracy
This is one I have issues with. How accurate does a human drummer need to be? If you look at recordings of a good real drummer, there's a lot of variation in how accurately they hit compared to the beat. But it will still sound in time. The issue I have is that it's against my understanding that being inaccurate is the right thing to do, just feels wrong to admit that, but it seems that being slightly inaccurate is the way to play. Goes to show that none of us are perfect. I tend to keep the main beat very close if not exact and vary other hits. And I always think about using groove features or humaniser functions.
In the Mix
The drums coming out of most samplers are still a raw instrument sound. There may be some reverb and compression but do they suit the music you're writing? If not, remove them and add the processing you want to add. More so, you may want to change the sound of a single drum, e.g. wanting to compress the kick drum more and add more of the click from the beater with eq. If so, then it's best to separate out the drums into separate outputs. You can then modify the sound of the individual drums to suit your tastes.
While you're at it, decide how you want the drums to sound in stereo. Are they all central? Or should it be set out from the drummer's or the audience's perspective. Then group them back together for drums for ease and so you have the option of processing the drums as a whole.
Other techniques
Harmony Central has some great suggestions for more advanced techniques. The concept of mute groups looks especially useful.
Reference CD
What should drums sound like? If you're aiming for realistic drums, then you'd do well to start with some reference files
There is some interesting information about the Led Zep sound over at Guitar Player
Learn to drum (even if only in theory)
Have a look round for lessons on the rudiments of drumming. Being armed with this information will help you create more realistic drum loops. I learnt by sitting in front of a kit twice a week and getting a few pieces of advice every month. No proper lessons. Even so this basic introduction helped me understand no end what it means to create a drum track. Understanding what constitutes a basic beat is the starting point. Try starting with these:
Shavano has an old but still useful article for anyone wanting to program drum midi patterns
Drum Plug-ins
I mentioned drum plug-ins above. I don't use the more advanced plug-ins so I can't really comment beyond that I've heard some very positive reviews including from some good drummers. From the demo samples I've heard, they introduce a level of realism that is difficult to achieve on your own with midi programming. There's a range of drum plugins offering different functionality.
The simplest are just sample triggers where you select the samples to be played and place them on a midi track. This is the basic type that you'll find with a lot of DAWs. If you're lucky, you can select from different drum sets, create your own, change the relative volume and/or pitch levels or even modify the envelope of the individual drums.
More advanced plug-ins allow you to select more authentic-sounding drumsets, designed to sound like specific Pearl or Ludwig sets and so on. They'll also give you the option of room sounds, microphone types and microphone placement. Extra features include the ability to blend the mic mixes. As they get more advanced, the plug-ins interpret the midi input into something more like what a drummer would play. This is the type that interest me more than others.
Some include drum patterns in a variety of styles, giving you the ability to compose the song's rhythm very quickly. They may even include intro and fill patterns. Remember the basic sampled drumkit on the old casio homekeyboards of the 80s? Well, this feature's a more advanced and flexible version of that. It's ok for using when keeping a beat, especially as a more interesting clicktrack, but I wouldn't use them in the end product.
Part of a series by Award Sounds offering a selection of creative ideas to kick-start or rejuvenate a composition.