How Do Electronic Drums Work?
If you’re a beginner, or ‘crossing over to the dark side’, you might wonder, how do electronic drums work? – Here’s how…
The digital revolution has transformed the world of musical instruments. Nowhere is this more apparent than in the world of electronic drums.
Nowadays, the digital drum kit has become the beginners’ first choice to learn upon. The main reason for this is the low noise levels offered by an electronic kit. For those who don’t have understanding neighbours, or a soundproofed cellar, digital drums provide the perfect solution. You can even plug in headphones, making practice very quiet indeed.
For those toying with the idea of going digital, you may still wonder, how do electronic drums work?
This guide will cover the basics of how a typical kit functions.
The brain/ drum module/ sound module
You might have heard reference to ‘the brain’ when people talk about electronic drums. Whilst it might sound as if your kit is plotting to take over the world, the truth is a lot simpler.
The brain is another name for the drum module or sound module. Essentially, this box of tech-trickery is a synthesizer that generates all of the drum sounds, along with running all of the other features of the kit.
These days, even the most basic of digital kits offers a selection of different kit sounds. So, if you’re playing a rock track, you can select a suitable rock kit, for example. Typically, you’ll get the most commonly used styles of drum kit- rock, jazz, brush, vintage electronic etc.
Better kits tend to offer more choices of kit presets. In addition, well-equipped kits will offer the ability to set up your own kits from the individual onboard drum sounds, or edit the sounds further.
At its most basic, this will include the ability to tune individual drums, adjust individual drum volumes, dampen or EQ them. At its most involved (such as on Roland’s flagship TD-30 range), the user can effectively design their own drums, specifying dimensions and materials of individual components.
The vast majority of drum modules operate using PCM sample sound technology. This means that to generate sound, it replays high quality digital recordings of drum sounds when trigger pads (the bits you hit with sticks) are struck. If you are playing, say, a birch kit preset, then the sounds will have been recorded from a real birch kit.
Roland V-Drum kits are slightly different in this regard. From the TD-11 upwards, these employ the flagship SuperNATURAL sound technology, to generate sounds. Whilst this uses samples as its ‘raw’ source, it uses some incredibly clever mathematical modelling technology to more smoothly and authentically recreate the subtleties of a real drum kit.
Combined with its behaviour modelling technology, this means that, for instance, it recognises if you’re playing a cymbal swell, and adjusts the sound to mimic that of a real cymbal.
Other features of the brain may include accompaniment styles to play along with, the ability to record performances, or onboard coaching exercises.
Though in many respects, the brain is much like a synthesizer sound module, the connections to the rear set it apart.
The brain has inputs for each of the individual drum triggers (Roland V-Drum kits tend to do this via a loom these days- this is a cable that connects to the module with one large connection, but has many individual connections for triggers on the other).
This brings me neatly on to…
Drum triggers/ trigger pads
Trigger pads are the bits of an electronic drum kit that you play. Most digital drums are a standard, 5-piece configuration, much like the sort of acoustic drum kit that you would commonly learn to play on.
This comprises an input for kick drum, snare, three toms, crash cymbal, ride cymbal and two for hi-hat (one for the trigger, and another for the pedal to open and close it). Higher spec drum modules may offer additional trigger inputs, should you wish to add more at a later date (see image above of trigger inputs from a TD-30).
At their simplest, drum triggers have a type of pickup that senses vibrations (a bit like piezo pickups found in guitar bridges). When the trigger is struck, the pickup senses not only that it has been hit, but how hard, according to the level of vibration.
Of course, modern triggers are more sophisticated than this simple explanation. These days, many kits feature drum triggers that have multiple zones to trigger different sounds. These are used so that the rim and skin trigger different sounds on pads, or the bell, bow and edge of a cymbal trigger different sounds, for example.
In addition, many triggers employ multiple pickups for dynamic and responsive triggering.
And that is how electronic drums work, in a nutshell. Simple, eh?