One of the most fascinating and useful tools to come out of the recording industry in the last 30 years is Musical Instrument Digital Interface, or MIDI. MIDI allows access to virtually any sound ever recorded through one instrument! Before we get into recording techniques and guitar specific equipment, let’s learn a little about the differences between MIDI and everyday audio recording.
MIDI and standard recording techniques
The basic difference between MIDI and standard recording techniques is the signal that’s sent to the recorder, or in this case, a digital audio workstation (DAW). During a standard audio recording, the recorder will record the actual sound wave onto whatever medium being used and keep it. The recording engineer can then modify the sound however he or she wants and whatever the recording platform will allow. During MIDI recording, the instrument, which is known as a MIDI controller, sends a signal code to the computer. The computer recognizes the code and assigns it to a particular sound. Think of the computer as the “brain” of the controller; the brain can assign one of hundreds of thousands of sounds to any particular command, or note played by the controller. Usually, it’s the pitch of the note that was played; if the musician plays an F, the MIDI computer will generally play an F using whatever sound the user has programmed. But MIDI can be used for other sounds; any note can trigger a tiger roar, a waterfall, a machine gun, or many other endless possibilities! If this sounds complicated, think of it this way: using a MIDI controller on your guitar, you can make your guitar sound like everything from a drumset to a saxophone to a UFO!
Transforming your guitar sound
Now, in order to transform your guitar into a drumset, intergalactic ray gun, symphony orchestra, or anything else, you’re definitely going to need some equipment. Most MIDI controllers are laid out like a piano keyboard, but have no fear; electric guitars can be converted to put out MIDI signals as well. Remember, when you record with MIDI, you’re not actually recording physical sound waves. Rather, you’re telling the MIDI computer what sound to play with a computer signal. This means the standard pickups on your guitar won’t do any good. In order to use MIDI, you’ll need to install a MIDI pickup onto your guitar. Fishman, a quality pickup brand made famous for acoustic-electric pickups, has a popular MIDI pickup that’s relatively easy to install, and Roland, perhaps the premier name in piano synthesizers, has an entire MIDI system for guitar (we’ll get to that a little later). Roland also makes a separate guitar that comes pre-installed with a MIDI pickup. The MIDI pickup looks different than a standard guitar cable, USB port, or Firewire Cable, and if your interface doesn’t have a MIDI input, you will need to purchase a converter.
The right guitar to MIDIfy
Now, before you go retrofitting your 1959 Les Paul with a MIDI pickup, keep in mind that you are not only modifying your guitar, but essentially rendering all the physical sound aspects of your guitar null and void. Since the MIDI computer will create the sound, things like tone and sustain no longer matter. As long as the playability of the guitar is solid, then the MIDI system will do the rest. I would suggest picking up a cheap but solid entry-level guitar for a few hundred dollars and experiment on that before you drill holes into your prized possession. I have a 1966 Fender Mustang that most certainly will not be receiving a MIDI pickup anytime soon, but an old Squier Strat that’s easy to play would be perfect for one.
Let's start making some noise
Once you’ve installed the MIDI pickup, you now need a “brain” for the signals your guitar is sending. If you’re recording, many DAWs have pre-loaded MIDI sounds as well as sound packs you can purchase. As with anything else in music technology, the quality of the sounds depend on how much money you’re willing to spend. On the low end, you’ll get a few options that are fun to play around with. On the high end, you’ll find entire sets of specific sounds for absolutely anything. Animal noises? Sure. Full symphonic orchestra? You bet. Looking for drum sounds that you never knew existed? Those are available too. Roland also makes a “guitar synthesizer,” which you can plug into an amplifier. The sounds are very high quality, and I have to admit that I’ve spent many hours in a guitar store playing around just making bizarre noises for fun.
Editing your sound
One extra benefit to using MIDI is that because you’re dealing with computer signals and not actual sound waves, the editing process is very simple and streamlined. You can move pitches, change sounds, quantize tracks and do pretty much anything else without actually modifying any audio. This results in a much cleaner and less destructive editing process. It’s simply changing the computer code as opposed to restructuring a sound wave you’ve recorded. On most DAWs, the interface to modify the MIDI signals is easy to navigate. You won’t have to re-record anything unless you actually want to.
Now that we’ve talked about the basics of using MIDI as a guitarist, it’s time to get out there and get some hands-on experience. Using guitars as MIDI controllers is relatively less common than using keyboards, but if your guitar skills significantly outweigh your piano skills, than using a guitar to send MIDI signals is an incredible tool. Also, for some instrument sounds such as banjo, mandolin, baritone guitar, bouzouki, oud, or anything like that, a guitar will send a more realistic set of signals to the MIDI computer than a keyboard will, simply because of the style of play. With MIDI, the sky is the limit as to what sounds you can make, so get to recording!