Why bother with MIDI?

"I don't want to become a geek or a techno freak. It can't be that important, can it? I mean where's MIDI on my Technical turntables, or my PC, on the pipe organ at church, or my XBox? Where's MIDI on my collection of 70s funk? Heck, MIDI wasn't even invented then was it?"

No, you're right, it wasn't. You're also right that MIDI has not somehow managed to worm its way into anyone's collection of vinyl. But you're wrong when you say it can't be that important. Whether you know it or like it or not MIDI has been driving recordings from gospel to speed garage since the mid 1980s. How many? Hmm... probably about 98% of them.

Whatever you're doing, be it selecting new music on a video game, or a ringtone on your cell, whether you're using sampled loops in Reason, or simply playing a nice shiny new digital piano from Yamaha, MIDI has almost undoubtedly been the force behind the material you're hearing. Now if you really don't want to do much else than 'replay' material then the fact of this underlying technology being MIDI may indeed not be that important to you.

But if you want to be creative, if you don't want to sound like everyone else, frankly if you want to save an awful lot of money, then MIDI is well worth investigating. MIDI opens up a world of possibilities because MIDI is just a control language. It is not fixed in terms of sound. MIDI can be used to control sound generated by any music technology, from any manufacturer. And not only the raw material but the final mix. And not just the level of the music but also the lighting! This is powerful stuff alright.

This series of articles takes a broad look at how MIDI fits into many types of musical environment. We'll look at what you need to know (not nearly as much as you'd think), what equipment you'll need to use (some of which you probably already have), and all the many tips and tricks you can use to improve the range and quality of your music with MIDI.

A little history

First things first. MIDI stands for Musical Instrument Digital Interface. It came into being in the early 1980s and was first seen on the Sequential Prophet-600 synthesizer. MIDI was put together initially by a few visionaries in two synth companies; Sequential Circuits in America, and Roland in Japan.

MIDI's initial motivation was simple enough. It was just an attempt to let you connect two keyboards made by different manufacturers; play one, but have sound coming out of the audio jacks on both. Layer them up in other words.

To do this there had to be an agreement on matters governing pitch, gate time (note duration), pitch bend etc. so that if you played Middle C on your Roland synth you'd also hear Middle C on your Sequential.

All about control

Having agreed upon how the data would be handled, a physical linking device had to be chosen. What they came up with was the five pin din connector (even though only three of the pins are actually being used in MIDI). Why? Cost, basically. These connectors are cheap, and plentiful.

MIDI's initial 'only' application, and one that is still perfectly relevant today, is that you take a MIDI cable OUT of the instrument you are physically playing, and plug it IN to the instrument you want to control. However, in order to hear sounds on this 'slave' instrument, it must be connected to a mixing desk and speakers, or headphones...

This is a very important concept to grasp because MIDI is just a control language. MIDI does not contain sounds, or audio, or anything other than lots of little ones and zeros (it's a binary language) that tell other pieces of equipment what to do.In its most basic use, all MIDI is doing is saving you playing the exact same part on the second keyboard in order to achieve a sound-layering effect.

Channel Surfing

Layering two synth sounds is cool, but how about layering up ten synths? And how about layering sounds on synth # 1 and # 2 for one sound and # 1 & # 3 for another? Fortunately for us these issues were discussed before the MIDI specification was completed and the gurus came up with a pretty neat solution: channels.

MIDI provides for sixteen channels over which devices can communicate. These so-named "MIDI Channels" are individual paths over which instruments can communicate using just one cable.

If synth # 1 & # 2 are both operating on, say, MIDI Channel 6 they'll be able to talk. But if synth # 3 is 'receiving' on, say, MIDI Channel 7, it won't hear synth #1. If you want it to be part of this new sound just switch it to MIDI Channel 6. Alternatively if you want a brand new sound comprising synth # 1 and # 3 you can switch synth #1 to MIDI Channel 7.

The language MIDI uses is Transmit and Receive. The Transmit channel is the one an instrument uses to send data OUT. The Receive channel is the one it uses to communicate with data coming IN. Sometimes you'll see the abbreviations TX and RX. TX is for Transmit. RX is for Receive. You need to remember just two things from this story: 1. in order to communicate, connected MIDI devices must be on the same MIDI Channel. 2. There are sixteen MIDI Channels to choose from.

Who's the boss?

A final piece of technical info in the first of this series of articles concerns the thorny question of who's in charge. MIDI has three connectors, often referred to as MIDI 'ports' or 'jacks'. These are: IN, OUT, and THRU. Misconnections in this area have caused more problems and red faces than any other MIDI matter I can think of, so let's get this one right.

Whoever is generating the commands, be it your own fingers on a keyboard, or a computer sequencer, or a new Roland drum pad... the MIDI needs to come out of the OUT port. If you're giving the orders sound comes OUT of your mouth, right?

If you have two synths, a Yamaha and a Roland, and you want to play the Yamaha and hear both the Yamaha and the Roland, you plug a MIDI cable into the... OUT (well done) of the Yamaha and... (you got it) to the IN of the Roland. If you ever see two devices connected OUT to OUT or IN to IN you can rest assured nothing is going to happen. If two people are standing toe-to-toe both shouting orders, or alternatively standing toe-to-toe just listening and waiting for orders not a lot is going to get done. Someone has to say something. Someone has to be listening.

A 'master' or 'controller' keyboard is the instrument you're going to use for playing. These instruments don't have to actually produce any sounds at all. Many manufacturers produce dedicated controller keyboards that come with all manner of controlling bells and whistles. But you can just as easily use your trusty Motif or Triton as a master keyboard. We'll look at the benefits of dedicated controllers later in the series.

Still with me? OK, so where does the THRU come in?

THRU passes on information that is coming into an instrument's MIDI IN so that you can then link up lots of devices. A THRU is only going to work if you have a signal going into the instrument's MIDI IN. It'll then accept the data and pass it along to the next instrument, merged with whatever is transmitted from that instrument's MIDI OUT. You go from a THRU into the next instrument's MIDI... yes, well done, MIDI IN. And so on.

Finally, finally, MIDI is a one-way street. If you connect two instrument via their respective OUT and IN jacks you'll only get communication from the OUT to the IN. If you want to two-way communication, you need to connect a second MIDI cable. Depending upon what you're connecting you may end up with what are called MIDI loops (think of it as digital feedback), but we'll deal with that later on in the series. For now just understand the concept of MIDI traveling in one direction at a time down one cable.

Why keyboards?

Why indeed? MIDI was invented by a predominantly keyboard-orientated industry. But remember MIDI is just a control language. You can generate MIDI data from a knob, from a slider, from a MIDI drum pad, from a computer, from a MIDI microphone, from a MIDI guitar. One of the slam dunk best things about MIDI is precisely this type of open ended-ness and flexibility.

Although there are plenty of what are called 'alternate' MIDI controllers (guitars, wind instruments, drums, gizmos, and boxes) I believe we are still in the early days of MIDI controlling devices. Most alternate controllers are MIDI versions of instruments designed hundreds if not thousands of years ago. Considering today's almost limitless number of sounds and technologies it's crazy that more genuinely alternative controllers that cater to today's mind-bending range of sonic possibilities have not been developed. Again we'll explore some of the options later in the series but for now just dispose of the idea that MIDI is a keyboard playing thing. You do not need to have had ten years of piano lessons to use MIDI. You don't even need to know what a piano is.