What is MIDI and How Can I Use It?

Anyone reading through the specs of an effects processor or has ever bought a keyboard has seen the word MIDI. What is this crazy thing, and will it make my guitar sound like an 8-bit Atari game? Am I going to have to dig out my protractor and sextant to understand how MIDI works? This article will demystify this protocol and showcase how MIDI can make our guitar rig work more logically and efficiently.

What does it mean, anyway?

MIDI stands for Musical Instrument Digital Interface. Back in the 70s, if you were a keyboardist and you wanted different sounds, you needed different keyboards. Fast forward a few years, and manufacturers came up with their own ‘language’ which would allow their own keyboards to talk to each other. In other words, with just a cable, you could play one keyboard, and hear the sound of both keyboards without having to press the keys of the second keyboard. Problem was, it only worked if both keyboards were made by the same manufacturer.

In 1982, a common language was developed that allowed devices from any manufacturer to speak to each other. This was a big deal, as most companies were very protective of their technology, but feared that incompatibility would eventually lead to less sales. So they worked together to allow a way for different pieces of gear from different companies to speak to each other.

MIDI isn’t a type of sound, it is a language

This sounds nothing like Jimi Hendrix.
This sounds nothing like Jimi Hendrix.

To explain this, it is much easier to understand if we use keyboards as an example. MIDI is a protocol which can send a message to a specific instrument. In other words, it tells the instrument what sound to use (program change message), what key to play (note 0n message), how hard to hit the key (velocity message) and to add more reverb (continuous control message). It can also be used to back up the sounds or update the firmware (system exclusive message). Of course, there are many more types of messages, but these are the basic ones.

So, you connect them all together?

In receives the messages, while out & thru sends them to the next device in the chain.
In receives the messages, while out & thru sends them to the next device in the chain.

Well, yes, by using a MIDI cable like one pictured at the top of the article. It is a 5-pin cable that has to be plugged in to all the device in the daisy chain. Most midi devices have three sockets: MIDI Out, In & Thru. MIDI Out is where you plug in the first cable- it sends messages from the first device to the second. MIDI IN is where you plug the cable into the second device. It is receiving messages from the first device’s MIDI Out. A cable from one device’s midi THRU just sends whatever messages it receives from the first device THRU the second device and out to the third. This is what you would use to daisy chain devices together.

So: MIDI Out>MIDI In>MIDI Thru>MIDI In>MIDI Thru>MIDI In…etc. Out is generally used only on the ‘master’ device – the first one. It’s controlling the sounds on all subsequent devices.

Yeah, but, um, I play guitar….

This is a midi footcontroller which stores all of the instructions for the devices it controls.
This is a midi footcontroller which stores all of the instructions for the devices it controls.

In the 80s, when giant racks full of blinking lights were pushed onto every stage, MIDI was used to switch sounds. A foot controller was at the guitarist’s feet, and when he/she pressed a button, it told the first device to turn on a chorus, the second to add a compressor, and the third to turn on a delay set for a specific time. Each device was on a unique channel, so it wouldn’t get confused by listening to instructions meant for another device.

This did mean lots of programming for the guitarist, since each effect unit had to be programmed to get the right sound and the footcontroller had to be programmed to send the right message to the right device. This was before computers made programming easy – usually you had to stare at a very small LCD screen. To make matters worse, some commands used the MIDI language, which is in hexadecimal (base 16) language. Yeah, fun.

Now all of this is tedious, and really the opposite of just rockin’ out. However, it is pretty cool to step on a button and change the entire configuration of your rig. On one patch, the expression pedal controlled the wah, on another, it controlled the delay time. Those precise sounds which were only available in major studios could be had by programming those sounds into your rack effects, and programming your foot controller to select those sounds.

OK, this makes me happy I didn’t grow up playing guitar then

Well today, MIDI means a few things to guitarists. It can mean MIDI guitar, which adds a hex pickup to your guitar, and tells a synth what sound to play, what note to play, and for how long. I have used a MIDI guitar system for years, and it is a blast triggering choirs and piano on guitar.

However, most guitarists today are using MIDI for just a few things. Programmable amps allow you to set the knobs any way you want, and then save it. You then use a foot controller to select a specific sound (program change message) and possible modify that sound, like raising the gain for the solo (continuous control). In other words, program change messages select a specific patch (or program), and continuous control messages allow you to change the sound by modifying a parameter within the same program.

Keep your effects off the floor...
Keep your effects off the floor…

Far more common in the world of guitar these days is the programmable effects switcher. While multieffects allow you to string together multiple effects in one box, the programmable effects switcher allows you to use your own stompbox collection. Each effect gets plugged into the switcher (usually housed in a rack- the effects go on a shelf in the rack too), and pressing a button on your foot controller sends a message to the switcher to switch on specific effects. Sometimes it is difficult to stomp off a chorus, delay and compressor, then switch on two distortion boxes, a long delay, and a phaser in the time between a verse and a chorus.

The switcher saves the on/off status of each effect as a program. Your foot controller uses a program change message to send the switcher a command, and it automatically plugs your stomp box into the audio path. This keeps the ped
als off the ground (and safe) while taking ones that aren’t on out of the audio path until you need it. There are no patch cables between effects that can go bad at a show, and when you aren’t using any effects, it is like you are plugging directly into your amp.

MIDI can change the sounds in a virtual Guitar Rig too.
MIDI can change the sounds in a virtual Guitar Rig too.

With computers and iOS devices so prevalent in our lives, it has made programming the right sounds for our songs so much easier. No more decoding hexadecimal commands, and no more bending over a 2 x 24 character LCD screen. Most programming is icon-based, and logical. Sounds are more easily shared among communities online too, and there is always help available in online forums.

Are you the kind of guitarist who meticulously sculpts your sounds, or do you just plug in and rock? Do you use MIDI for anything in your guitar rig?

Join the Conversation


      1. I think he’s saying that only people who play acoustic guitar should be allowed to leave the house. That or nudists.

      2. I’m saying it’s not my thing. If it works for you and what you play then go for it. If you have faith in your style and equipment, for most genre’s, all the tech stuff isn’t needed. If you play in a group that tries to cover every genre of music or you typically play different styles in one show then it’s probably a great thing for you. For me, a simple rock/blues player I depend on tube amps, quality cords and a guitar with great tone no matter what it costs. I own some cheap guitars and some high end one’s, my 67 SG is the crown jewel of my collection. I am a huge Rush fan and they midi the hell outta stuff. If you are insecure about it then perhaps you shouldn’t read others opinions or talk to purists. Sorry if I offended you, it’s just not my thing.

        1. Oh that’s cool…there is room for everyone in this ocean. I respect that it isn’t your thing, but from your comment above, it sounded like you were dissing anyone who used it- that they should just stay home. After explaining it, I see that isn’t what you mean. With just words, it is difficult to tell if you are stating your opinion or making sweeping generalizations about every type of player out there. Although, strictly speaking, ‘go natural’ would mean an unamplified acoustic guitar, and certainly dismiss your own SG and tube amps.

          1. All true, I have several acoustics too and have played some coffee houses and small venues unplugged. NEVER dismiss the power of the SG and a Marshall rolled wide open, Pure Angus lol..

        2. Actually, It’s more cheap for me to get Guitar rig, a guitar interface and use the Mesa emulator, of course it wont sound as an actual dual rectifier, but its the closest thing I have

  1. a hexpander will be one of my next purchases , so i can play saxaphone and a sitar on my geetarrrrrr.

  2. I find this very interesting because I am a programmer by day. I used to use the software tuxguitar before I could afford my own. But I much prefer plugging in and rocking out. Having said that, I’ve never touched a midi guitar.
    Thanks for the awesome read! I hope others find it as interesting as I did.

  3. I find that to many complicated setups, buttons, switches, and programs can sometimes inhibit a live performance. I like to keep the live performance setups as simple as needed to get the sounds I need. I like just using the 5 most important stomp boxes and thats it. The boxes are On/Off, how much simpler can that be? Quality
    pedal board, cables, power source, and I’m good to go!

    1. Simplicity has its place, and I use simple setups a lot. But if I have a sound in my head, I am going to do what I have to so I can get it out. Sometimes that is with stompboxes, and sometimes it is with a computer or sampler. I welcome any diversity in getting original sounds out of our instrument.

      1. I like PodHD direct to board and monitors …nothing more simple then simply stepping on one pedal for exact sound I want. If no board/monitors in a small place .. then I loop into power amp section of tube amp and use cab with FFR speakers ..still simple.

        1. I do this too! When we use IEMs, I go direct. When we are playing a place with a backline and traditional monitors, I will use a Line6 M9. The least that can go wrong, the better.

          1. The M9 has interesting ins/outs for midi and fx and looping all in one but what do you use for pushing your sound when not going direct ..what do you plug the M9 into? The M9 with a fav amp of some sort? I prefer the PodHD series as all my amps and sound ideas are right there no twittling after an initial sound check.

          2. Really nice choices ..I love it for recording. Not real familiar with the Blue Angel .. gona read up on it.

  4. Unplugged years ago…nothing like natural string tones, can’t cover that up. Nice to play with though, tech’s come a long way.

  5. I agree 100%. There is no room for innovation, progressive ideas or new sound in music. That damn electric guitar screwed everything up. Give me a good old flat top, bag pipes or ‘cordine any day.

  6. I don’t own a violin. But I can record my Ovation into my DAW and double some of my guitar passages by converting my guitar audio to midi and choosing a Violin VST to playback the notes I played on the guitar and then occasionally throw in a flute doing the same riff .. saves time and makes me sound like an entire Irish band when I want to.

  7. I’ve been using midi switching since the late eighties, I’m glad somebody thought of it. I use different settings for different songs. It would sure be a chore to have to bend down and turn knobs to set up for the next song every night. Don’t get me wrong, I love my straight in sound, but, I like being able to switch it all up by hitting one footswitch.

  8. I’ve never played guitar with any sort of MIDI in my rig, but I have wanted to try it out. I love the way my pedals sound (I have tried multieffects boards and found their sound to be too “computerized”) and would love to be able to only have to hit one button to throw my distortion and chorus on while disabling my compressor or acoustic modulator.
    I also like to keep it simple too though, not have to think too much and just being able to play. But I do understand wanting that sound I have in my head or just got out of my rig (that I know I wont be able to reproduce again). I see where it could be useful in both the live and recording settings. Maybe I’ll try it out some day.

  9. Midi is getting easier and I think more people will come around to it soon. It helps me focus on the live performance by programming all my pedal changes in to patches. Be more dynamic is what I’m shooting for. Going from a clean tone (comp, timmy, long delay) to a crunch tone (stacked drive pedals w/ a trem) by just stepping on one button lets me focus on getting into the song and having fun instead of turning things on/off.

  10. Great Blog post: I’ve just got into the Midi thing.
    I use a TC Electronics M300 Multi effects/reverb with my Peavey 5150 and a Voodoo labs Control Switcher.
    I have a Rolls Middibuddy pedal to handle my presets.
    Basically I have
    Preset 1: Lead Channel- Live Reverb-No FX
    preset 2: Lead Channel-Club Reverb- Chorus
    Preset 3: Lead Channel- Live Reverb- Dynamic Delay
    Preset 5: (Second row on controller): Clean Channel- Spring Reverb- No FX
    Preset 6: Clean Channel- Spring Reverb- Chorus
    Preset 7: Clean Channel- Spring Reverb- Dynamic Delay
    It’s a lifesaver for some of our stuff as I have to go from Vanilla dirty to clean w/chorus in 1 tap.

  11. If i use Axon ax 100 MKll as guitar synth and for example line6 PODHD500 as preamp/effectprocessor and Behringer FCB1010 as MIDI foot controller (and Marshall Class 5 as amp) what computer editor should i use to program the FCB1010 to control the whole rig? (I use windows 7 32 and 64 bit OS).

  12. This all seems so overwhelming. Say, for instance, I want to create a patch that, among other things, performs an octave sweep (think Tom Morello – Killing in the Name of or Like a Stone). I can get the expression pedal to turn the effect on/off but cannot get it to sweep the full octave range. I have a preset that sweeps down a third but the parameters in that patch don’t allow a value any higher or lower than +3/-3. Am I using the wrong CC? What is the correct one?

  13. Fantastic post for students…
    It sure gives you an appreciation for musicians in the 70’s & 80’s 😉
    Great read. Thanks!

  14. Just a random doubt here. Can we use the midi channels of a guitar multifx to control guitar software like BIAS, AMPLITUBE, etc?

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