What is Polyphony?
Polyphony is simply the number of notes that a keyboard or device can be playing at any one time. So, for example, if you press two keys at the same time, you’re using 2 notes of polyphony. Simple, right? Well… not exactly.
Another way to use two notes of polyphony would be to hold the sustain pedal and hit the same note twice in a row.
Additionally, playing a note in a “Combi” mode (where sounds are layered or stacked on each other to make rich tones) allows you to use up many polyphony notes with every single key press.
Polyphony is also used when running a sequencer or record function, playing a keyboard’s on-board drums, using the song or style arranger, etc.
So, you can see it is important to understand the ramification and how polyphony fits into your playing style and available equipment.
What is Multi-timbrality?
Being “multi-timbral” can be related to polyphony, but is actually the ability to play multiple types of sounds at the same time. So, you want to play a bass line with the left hand and piano with the right? You’ll need multi-tembral capabilities in your keyboard.
Many times the different sounds are separated onto different MIDI channels and can be manipulated on a channel by channel basis. But often, as seen in many lower prices models, the keyboards are not multi-timbral and can only play one sound type at a time.
Obviously the more use you make of your keyboard’s multi-tembral features, the more available polyphony you will need.
Why should I care?
Polyphony is very important. The last thing you want to do is to get home with your wonderful new keyboard or sound module, start playing and discover it can only play 16 notes at a time. 16 note polyphony. If you find that to be the case, you might as well throw your sustain pedal out the window. You won’t be using it.
It’s like this… you have 10 fingers. if each finger plays two notes (in a run or in repetitive strokes) and your polyphony is 16 notes, you’re 4 notes over the limit right away. The keyboard will start to shut off previous notes to compensate for the new ones. Although sometimes it’s okay, this usually sounds bad and ruins your musical experience.
Some lower end keyboards can be in the 8 to 30 polyphony range (or less). Most higher end keyboards these days come in 64 to 128 note polyphony. This is pretty good for playing individual instruments that aren’t layered and many pad/synth or multi-layered sounds. But if you’re going to be doing any major composing or orchestrating, you may likely need even more.
What can I do about it?
If you are stuck with a keyboard or sound module that has a low limit for polyphony or you find you are pushing the limits of what it can output, there are couple things you can do.
1. Get another sound unit. Purchase an additional sound module or keyboard and connect them using MIDI. This will double (or more) the polyphony available to you. Plus, it’s always fun to get new gear.
2. See if your sound module is expandable. Often you can buy cartridges or expansion chips that will increase the functionality of your existing device.
3. If you’re making complex arrangements and running out of notes, you may need to record some of your tracks into a computer, converting the notes into audio waveforms. This will allow you to shut those notes off in your arrangement and free up some polyphony.
If anyone has any suggestions, or more Polyphony tips, please comment below.