In The Beginning
All drums, acoustic and electronic, use energy to create their sound. This energy is supplied by the force of a stick or mallet striking a tensioned surface. In acoustic drums, the surface vibrates and sound waves are created and then amplified by the drum shell. In electronic drums, the energy is converted into an electronic signal by a “trigger.” This trigger is embedded in an electronic drum “pad.”

There are two basic kinds of drum pads: gum rubber and mesh head. Gum rubber pads are coated with rubber, which helps absorb the stick energy and protect the trigger(s). Some pads have more than one trigger; a pad may have one trigger located in the center of the pad and another one around the rim. This “dual-trigger” configuration allows more than one sound to be triggered from the same pad. For example, the center of the pad could trigger a snare sound while the rim triggers a cross-stick sound. Examples of dual-trigger gum rubber pads are the Roland PD-7 and PD-9.

Dual triggers are also used in Roland’s V-Cymbals to trigger bell and bow cymbal sounds and even allow cymbal choking. Some systems even have a “three-way” triggering capability for the ride cymbal—making it possible to play the cymbal’s bell, bow and edge sounds.

Pads built with rubber heads tend to be more affordable those with mesh head pads, but they are used on both inexpensive and top-of-the-line electronic drum kits. For example, Roland’s new V-Stage Set has both types. Gum rubber pads are very versatile and are also available in a variety of sizes. They can be used as drum pads and cymbal pads as well.

Mesh pads are more sophisticated and have some advantages over gum rubber pads. First, they have the realistic look and feel of an acoustic drum head since they can be tensioned with a drum key. Tensioning the mesh head on an electronic drum has no effect on the sound it’s triggering, but it greatly affects the feel. Second, mesh heads are typically quieter than gum rubber pads. They also come in single- and dual-trigger versions as well as in different sizes. Plus, mesh pads even allow the use of brushes. The new V-Stage Set has five mesh head pads, including the kick drum, which gives drummers a very authentic feel and response. Examples of mesh head pads are the Roland PD-120 and PD-100.

Hi-Hat Controller Input
Roland percussion sound modules also have a special foot pedal designed for controlling the hi-hat pad. The V-Stage Set, for example, includes an FD-6 Hi-Hat Controller, which has a smooth closed-to-open hi-hat action. It allows for pedal or heel hi-hat sounds and even “foot” splashes.

Sound Module
In electronic percussion, the pads themselves are designed to be as quiet as possible. So to be of any use, they have to be connected via cables to a sound module. This is often referred to as the “brain,” since it contains all the memory and is responsible for the functions of the pads. The sound module usually consists of the following: trigger inputs for connecting the pads, the actual sounds to be triggered by the pads, effects processing, audio inputs, audio outputs, a headphone output, MIDI ports, a sequencer and all the controls for creating and storing custom setups. The Roland TD-8 is a percussion sound module.

Trigger Inputs
As the diagram illustrates, a drum pad is connected to a cable, which is then connected to a “trigger input” on the sound module. Like the pads, a trigger input can be single- or dual-trigger. So, a dual-trigger input can fully accept the signals from a dual-trigger pad—thus achieving two independent sounds from the pad. This is done using the stereo cables included in all Roland drum sets. If desired, two single-trigger pads can be connected to one dual-trigger input using a splitter cable. This gives the option of having more pads to strike in a drum kit. In Roland’s new V-Stage Set, the TD-8 Sound Module has 10 dual-trigger inputs—eight of which are used by the included pads—so the kit can be expanded and customized by adding additional gum rubber or mesh-head pads.

MIDI In/Out
Another way to expand an electronic drum kit is through MIDI. Most sound modules have a MIDI Out port from which an external MIDI device (such as a sampler) can be triggered from the pads. MIDI In allows the percussion sound module itself to be a sound source if you are playing sequences back from an external sequencer or other MIDI devices. (More on sequencers later.)

Sounds and Outputs
When a pad is struck, the sound module is triggered and sound is produced and sent out the audio outputs. Some modules have simple stereo (left and right) outputs while more professional sound modules may have up to eight outputs for multitrack recording and live mixing purposes. A sound module like the Roland TD-8 (included with the V-Stage Set) has four audio outputs and contains hundreds of percussion and instrument sounds, any of which can be assigned to any pad. The TD-8 module uses a special technology called “modeling” (COSM sound modeling in Roland-speak) to create its sounds. This technology makes it possible to build each drum from scratch. As shown on the TD-8 display screens, you can select the shell material, head type and even the muffle type and amount. With COSM modeling, there’s no limit to the variety of drums and cymbals you can create. The sounds are organized into drum kits and can be customized to your liking and saved for instant recall at any time.

Most drum modules also have a “mix input”. This is effective for listening to an outside audio source that’s mixed in with the drum sounds. You can plug your CD or tape player into the mix input and play along with your favorite CD. In performance and recording situations, a click track can be monitored through the mix input. All of this audio can be heard by connecting the module to a speaker system or by simply plugging in a set of headphones. Headphones provide the ultimate in silent practicing and privacy.

Effects Processing
Most sound modules include some form of digital effects processing. Whether it’s reverb, delay, chorus, flanging, ambience effects (room simulation effects), or multi-effect algorithms, digital effects can greatly improve and drastically change the drum sounds. The effects processors in the TD-8 can create wild sounds or change the sonic environment to make you feel like you’re playing in a concert hall.

Sequencer
Most percussion sound modules include a sequencer. A sequencer allows you to record your own drum patterns and songs and also play along with those included in the sound module. And it’s not just drums! Sequences on the TD-8 have full instrumentation including a reference drum part (for style training) that can easily be muted when you are ready to play along with the sequenced instruments like bass, keyboards, guitar and more. This is a great learning tool and also tons of fun. Whether for practice or playing live, you can have a complete backing band at your fingertips. You can even start and stop the sequencer by hitting a pad on the V-Stage Set or any Roland kit.

Keep in mind, however, that a sequencer records MIDI performance data as opposed to the actual audio sound of the instruments. Consequently, a sequencer—unlike a tape player—can slow down or speed up patterns and songs without changing the pitch. So, if you’re able to play a pattern into the sequencer at a slow tempo, you can play it back at whatever tempo you want. Or, if you’re trying to learn a complex pattern, slow it down to make it easier to learn!

Hopefully, the technology and vocabulary of electronic percussion is no longer a mystery to you. If you’re considering electronic drums, check out the complete line of Roland V-Drums and experience the musicality of this amazing technology.