line 6 kb37 controllerWhat is a midi controller?

As we learned in midi basics there are basically two ways to get midi data into your computer.  You can manually enter notes into a software program using your mouse or keyboard or you can record the midi information using a controller.  There are controllers for guitars and other instruments but the most common controller is the keyboard.

Bigger is not always better when talking about controllers.  Full size keyboards are a must for live performance in in a studio where space is an issue a 37 key controller works just fine for entering drum patterns, melodic phrases or chord patterns.

Unlike a synth workstation, MIDI controller keyboards do not have sounds.  The assumption here is that you will be using your computer sequencer with software instruments, or will have MIDI modules making the sounds for your music.  The controller just sends MIDI data.

Because of the small footprint, fewer keys, and fewer functions, many MIDI controllers are quite inexpensive and are a great way to get started.  You can find MIDI controller boards for under $100, and if you have great software instruments, no one will ever know if you cut your tracks on it or a massive Roland.

Keyboard controllers come in 27 keys up to a full size 88 but I am going to look at the compact ones that work best in a home studio.  Measure your space and get a keyboard that fits your needs.  The size is not as important as the features we will discuss now.


Budget controllers are most apt to compromise on the touch of the keyboard.  This "touch" consists of may things.  1. The actual feel of the keyboard and its response to your hands.  2. The presence of velocity sensitivity.  3. Whether it has aftertouch or not. 4. Whether the keys are weighted or unweighted.  All four of these variables combine to make your playing of the keyboard a pleasurable experience.  As you go up in price you will find more of these 4 critical features implemented

1. Feel  This is subjective to some extent, but most of you can quickly identify a cheap feeling keyboard.  The keys will feel inconsistent when you press them; they may "bottom out" fast to even a slight touch, and have a flimsy cheap plastic feel.  While all of these boards have plastic keyboards, there is a difference between cheap, thin plastic and plastic of better quality. 

2. Velocity sensitivity.  The harder you play, the higher the velocity value is sent to the computer for any given MIDI note.  Nearly all software samplers and synths respond to velocity, which is used to control the loudness and timbre of the note.  The presence of velocity can make your playing sound expressive.  If you don't have velocity, the keyboard sends the same velocity value for every note, which can make even great playing uninspiring.  So make sure you at minimum get a controller that transmits velocity sensitivity.

3. Aftertouch  You engage aftertouch by pressing the keys down after the initial strike. They keyboard will send a range of 127 values as long as you are holding the key and modulating pressure.  When implemented well, this is just like turning a knob.  Is it important?  Many software synths do not implement aftertouch, though many of the better ones do.  Most hardware synths do respond to aftertouch.  There are 2 basic kinds of aftertouch.  The most common is channel (mono) aftertouch (sometimes called channel pressure) where only one data stream of aftertouch data is generated and it affects every key on the midi channel).  The less common, but more complete implementation is called polyphonic aftertouch.  Here each key sends out 127 values at the same time, which is harder to implement and generates a ton more MIDI data.  Only a few software synths respond to polyphonic aftertouch

4. Weighted, semi weighted, unweighted action.  You won't find fully weighted keys in a compact keyboard controller, but you may find it in 88 key controllers.  "Weight" is added to the keys themselves and to the key travel mechanisms to make them respond more like a real piano's heavier keys do.  This is usually not desirable in a compact keyboard controller, where playing fast is often desired.  An "unweighted" keyboard offers little resistance.  You can spot an unweighted keyboard by touching it; it will be extremely light feeling and the keys may be "springy".  Many compact controllers are "semi-weighted".  These also have a light touch but offer a little more resistance and consistency.  They usually have a better feel for most people.  

Controllers (knobs, wheels, sliders, touch pads, drum pads, program selectors and joysticks)

All Compact controller keyboards offer more controls than just the keys themselves.  At minimum, you will find some kind of pitch and modulation controls, which may be in the form of two separate wheels or a single joystick which combines the functions.  There is usually also an input on the back for connecting a sustain pedal.  Next, some boards have some kind of ability to switch programs and banks.  This is more important if you are controlling hardware midi synths, but less important for software instruments, where programs are more easily selected by the mouse, and which may not respond to these commands. Some controllers offer drum pads which can be assigned to the MIDI notes where drums usually reside on the keymap. (C0 to G1 typically).  Often that is an important consideration for those who want a dedicated surface for triggering drums.

So, what is most important to me?  do I need all of these features?  Personally I do not use many of them and i don't think you would miss them if you never had them.  I think that touch can be important because you want have a good feel when recording.  I think size is important because I like to keep everything set up and handy when inspiration strikes.  If your controller takes up too much room you will move it around and it will become a hassle.  I don't think price is a huge issue, $100 controllers record midi data the same as $300 controllers.  They just don't have as many bells and whistles.







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