Wednesday, December 15, 2010

A world without MIDI - The Korg Wavedrum

I recently purchased a Korg Wavedrum which I love. Realize, that I am not a drummer but lately have looked a way to add more rhythm to my songs. I also bought the Wavedrum because I consider it to be on the cutting edge of music right now precisely because it does not have MIDI (hushed sigh, people falling down from shock)

OK, you might think that I am either joking or crazy. MIDI is a great standard right? Well, yes and no. I hope by the end of this article I can both explain how the Wavedrum works (although part of that is hidden in its proprietary chips) but also why MIDI is not the be all and end all in electronic instruments and why it makes at least some sense for the Wavedrum to be missing MIDI.

Anyone who plays a natural instrument such as a guitar or violin, as good examples, knows that there is a magical interaction between musician and instrument. It's a kind of feedback loop. Musical expression, at least for natural instruments, is a complex interaction between the musician and the instrument. The first part of the loop involves both the sense of touch and sight. Although sight only functions initially to identify where notes are. A musician does not need sight to play an instrument but having a sense of touch is essential.
One can even speak of an instrument being embedded in our memories. Our brains even remember the sense of touch in what is often called muscles memory. Our muscles know where to go. A guitarist, such as myself, can bar a fret without looking to see where it is. Even the fine muscle movements for vibrato and harmonics can be learned so that they become fluid and part of the organic whole that forms the basis of musical expression.

One of the faults I see in MIDI is that music becomes quantized and loses expression. At firswt this quantization was time based but with the advent of autiotune, evenp itch is quantized. DAWs even intentionally quantize timing and notes that may not fall on the grid of time and pitch. Any musician will tell you however that musical expression lies in that space in between. The bend of a note or the ever to slight variation in timing can make for magical moments.

Physical instruments also vary from most electronic instruments in that notes are not simply turned on or off (as in MIDI). In fact, MIDI in some ways handcuffed synthesizers by making the keyboard, pitch bend and mod wheel almost obligatory. There are alternative controllers and Buchla has steered away from using a keyboard for it's modulars but for the most part this is true. For a physical system, the playing of a single note is a complex event. The note begins when energy is imparted to the system (or in terms of physics, the system is exited). For example, the guitar string is first stretched with a pick and then once released begins a kind of complex dance (we call this the transient) until it comes to an equilibrium. It is that transient where much of musical expression lies.
There has been a dominant belief in electronic music that the power of electronic instruments is in the waveform. I strongly disagree with this. In fact, studies show that a note cut of from it's transient leaves the listener unclear as to what instrument it comes from. It is also here that musical expression lies in all the subtle ways that that first excitation of a system occurs and resolves itself into a more stable waveform.

So why is all this important? Simple. MIDI ins and outs allow a musician to recreate a performance either through a built in sequencer, a DAW on a laptop or even a hardware sequencer. This is done by recording a MIDI data stream. Because of the nature of a physical instrument, one cannot re-create the performance on a physical instrument using MIDI. Sound can be sampled to create a snapshot in time but not the myriad of ways the musician is able to express themselves. For example, there are guitars that have MIDI outs or can use a MIDI interface but this can't be used to recreate a guitar performance only drive a MIDI synth. Roland V guitar system amd Line 6 guitars take a different route by using piezo pickups to first pick up vibrations and then use additional signal processing to create the final sound. This is what the Korg Wavedrum does as well.

Now its possible to put a MIDI out on a Wavedrum. Note on messages would be easy to create and even velocity. Drum head pressure could be used to map to pitch or aftertouch but these can only be used to drive samples not re-create the performance of someone using a wavedrum.
What is the Wavedrum? It functions somewhat like a Moog Guitar might with built in electronics but the Wavedrum's electronics are far more sophisticated DSP algorithms which process the signals from the piezo pickups (one for the head and two for the rim). These signals also trigger PCM samples which are mixed with the processed signal. In the case of "double sized" algorithms which are more complex, the rim and head and processed together. The head also senses pressure which changes the sound much like a drum head or also creates more ambient sounds.

The Wavedrum sounds and responds like a real instrument. It creates that two way feedback loop I talked about earlier which is lacking substantially in MIDI based electronic instruments. In many ways I would like to see at least some electronic instruments move in this direction. Sure, you can't duplicate the performance of a Wavedrum using MIDI but you can't do it with a guitar either and I don't see anyone stop playing and recording guitars because they don't have MIDI outs.

What the Wavedrum has over a physical drum is that its very very flexible. There are 100 presets and 100 user programs. The drum is programmed by a complex parameters which varies for each algorithm and are based on a generalized model of certain classes of drums. The PCM samples are used to provide a more specific type of sound which corresponds to various drums and percussive instruments.
The Wavedrum is a hybrid of samples and real sound and processing and I would love to see more instruments follow in this direction. Sure, moving outside the realm of triggered MIDI samples is scary to some who have grown up with them but I think its worth the bother.

1 comment:

Bucky said...

So a couple years later, I'm reading your comments as I ponder buying myself a Wavedrum. I'm a Celtic fiddler first and foremost, although I dabble in several other instruments. I am not a percussionist. I was wondering how you feel about the Wavedrum now that you've had a few years of time to play with it. Thanks!