Digital Piano POLYPHONY – What is it? | 2023 REPORT

Casio AP-470

In other words, if I am playing 2 or 3 sounds layered (mixed) together in the right hand along with 4 instrument sounds & drum patterns (which includes auto chord arrangements) in the left hand on a digital piano, and I am playing about 6 or 7 notes minimum at a time on the keyboard using both hands along with the sustain pedal being depressed by my foot at the proper times along with recording it on separate tracks, I would need enough polyphony (digital note memory) to keep it all going and therefore would need a lot of polyphony memory in the piano to do that. 

Yamaha – 256 note polyphony

So the general formula is: the complexity of the (stereo) piano sound sample in the piano, the amount of stereo instrument sounds & effects (reverb, chorus, etc) plus the amount of notes (keys) you’re playing at one time, plus the amount of pedal sustain time, and the amount of recorded parts (tracks) that you’ll be recording and playing back (assuming you’ll be recording things) equals the need to have enough digital processing power (polyphony) to keep that all going properly. If the piano/instrument sounds are all in stereo as opposed to mono (some pianos have stereo instruments and some do not), the digital piano may need to have even more polyphony to accommodate a stereo piano sound. In the “beginning” technology could only do 1, 2, 3, 4, 5, & 6 notes of polyphony sound processing power. Then there was 8, then there was 12, 16, 24, 32, 48, 64, 96, 128, 256, and so on. As technology progresses, it’s typical that manufacturers give you way more polyphony than you may ever need and this type of thing (having way more technology than you’ll ever use) is true of many electronic devices, computers, appliances, TV’s, etc, where people generally don’t use 50% of what that device is capable of doing with regard to its technology power.

32 note polyphony

Long ago when there was only 8 notes of polyphony in mono sound (I owned a few of those digital pianos & keyboards in the past) and you had two instrument sounds layered together at one time (in a layer like piano & strings) and were playing about 6-8 keys at one time in both hands (no drums or extra stuff on), you could only hear a maximum of 4 notes played on the keyboard at any one time because usually each sound took up one note of polyphony when you played the keys! In other words, you couldn’t hear everything you were playing because the piano ran out of memory! Notes would drop out constantly and it made the music sound very choppy and bad. If you tried to record that on a digital recorder in the piano it would only play back a few notes and sounds at a time and the song would continually be interrupted by the loss of polyphony or memory. It was a very sad time for me and others in the digital piano & keyboard world:( But it was all we had and it was certainly better than nothing.

Kawai – 192 note polyphony

Then over the years, little by little, digital keyboard manufacturers developed better technology and with that, more polyphony memory. Pretty soon I was able to play more songs with more sounds and better instrument sound realism without too much note dropout or sound interruption, but there were still significant limitations. But then came more sophisticated tones like stereo acoustic piano sounds with natural acoustic quality harmonics, overtones and string samples and more complex left hand accompaniments which all sucked up digital memory like a sponge. I remember playing not only professional music jobs, but also in church and schools for many years (I still do today) when people had little knowledge of polyphony and its importance. I was using a very cool Roland digital piano (at the time) with 32 notes of polyphony (wow!) and a sophisticated Kurzweil sound model with just 24 notes of polyphony as well as another sound module with 16-notes of polyphony all connected together with MIDI cables. 

That gave me a huge 72 notes of total polyphony combining everything and at the time, that was pretty much unheard of and I thought it was very “cool.” I had two sounds coming from the Roland, one sound coming from the Kurzweil, and one sound coming from the other sound module all layered together for a really full sound with minimal note dropout most of the time (depending on how I played). People couldn’t believe how good it all sounded. But that was many years ago and you had to know how to put all that together properly and make it sound good and most people could not do that.

Roland – 256 note polyphony

Now manufacturers have started to figure out how to put more polyphony memory and other ingredients (including more cool sounds) and much more realistic piano sounds at a lower cost (cost is always an issue) into one keyboard or digital piano so you don’t need to have (own) more than one instrument to do all the things you want to do with your music. So generally speaking, more polyphony “frees up” your music so you can use all the functions on the digital piano to their maximum. However, I will say that many cases, 64-notes of polyphony will be adequate for a lot of people people depending on how well they play, especially if they are playing just piano music at a beginner or intermediate level. But if you are more advanced or will be laying two stereo instrument sounds together, then at least 120 notes of polyphony would be necessary.

Korg G1 Air digital piano

If you want to progress as a player and eventually learn how to use more of the functions in your digital piano, especially if you are recording and then playing back your music up to 16-tracks using many notes, then be sure to get as much “polyphony” as you can for your budget. It’s like buying a computer these days…you may not use all the memory and speed it has right away, but you may want to know it’s in there in case you do:). I will say that having 120-note polyphony is more than enough note processing power for most people unless you are at a more advanced playing skill level. Some 120-note polyphony chips are actually expanded beyond their number because of multiple sample layers in the sound. Although 120 notes may be the specification, that 120-note polyphony chip can act just like a 256-note polyphony chip in terms of notes that can simultaneously be played and sustained. 

If you are doing multi-track recording with simultaneous playback of many stereo sounds and notes, then a larger amount of polyphony may be necessary to do that. Layering 2 to 3 sounds together and playing them live in a complex music score will not use up the polyphony unless the instrument cannot electronically allocate the polyphony correctly. A couple of Roland and Korg digital pianos are examples of 120 & 128-note polyphony respectively that can play without any loss of notes even with complex music be played by a professional pianist. It just depends how good the overall technology is inside the piano since there are other technologies involved in creating the actual piano sound in digital pianos these days. The polyphony number (128, 256, etc) is not always a good indicator of what you’ll actually be getting and the piano price is also not an indicator of the amount of polyphony you may get in that instrument.

Some of the newer top name brand digital pianos out there now have 256-note polyphony piano power and a few brands now have “unlimited polyphony” in their piano sound technology. So how can some of these pianos now have “unlimited polyphony” where there is no limit at all in using polyphony. Wouldn’t it be better to have 256-note polyphony or even unlimited polyphony in

a digital piano? The answer to that question is “not necessarily” because the polyphony number, regardless of what it is, is not the only criteria to having a realistic piano sound in a digital piano that plays and works well. 

There is also the sampling or physical modeling piano sound process the manufacturer uses which helps determine the quality of the piano sound along with how well the piano sound behaves with regard to “note-dropout” and “note

interruption which is more typically thought of by way of polyphony. So it is not always the polyphony number that determines the end result of the piano sound you hear out of any given digital piano…it is also depends on other things including “dynamic voice allocation” which is a separate, different technology in the piano which helps the piano polyphony become smoother and less likely to have obvious note-drop out issues. “Unlimited polyphony” is technology that has just come out in the

last few years in a couple of brands including some Dexibell and Roland digital pianos. 

However, high note polyphony or unlimited polyphony power is useless unless the piano sound itself is natural, organic and correctly emulates a good acoustic grand piano as closely as possible. The “quality” of the piano sound and its ability to sound natural and organic has to do with how advanced the piano sound creation technology is for these different digital piano companies I would personally have less polyphony and a better piano sound as opposed to the other way around. But fortunately most good digital pianos these days, especially in the higher price ranges, have at least 120 notes of polyphony with multi-layered piano sounds along with digital pianos that have 192-note polyphony and 256-note polyphony which can be counted in mono or stereo depending on its actual specification…and mono sound or stereo sound makes a huge difference in the polyphony specification. Stereo is always better.  

The bottom line is that “polyphony” and how it effects the overall results of your piano playing is only part of the issue and only part of the piano playing experience. A certain minimum amount of polyphony power is needed (about 64 notes mono memory for beginners or basic recreational players) but beyond that there are also other things involved in achieving a great piano sound offering plenty of natural organic tonal variations, long sustain-decay time for pedaling, stereo piano tones, and no noticeable note-dropout when playing more complex piano pieces or arranging complex multi-track recordings. 

Just be sure the digital piano you are thinking about getting has enough polyphony processing power to get the job done for your musical needs. If you are mainly just playing piano and not simultaneously using other sounds and digital features, then 120, 128, 192, and 256 notes (or more) is all you will need if you will be playing at an intermediate level or beyond. The more sounds you use together and the the advanced the music is that you are playing, the more stereo polyphony you will need and the more advanced the piano sound chip/engine needs to be. Please contact me before you purchase a digital piano from anyone anywhere and I can help you make the right decision in purchasing a new digital piano.

If you want to know more about digital pianos or want to find out how to get one for LESS MONEY than internet, Amazon, & store sale prices, please contact me at tim@azpianowholesale.com or call direct at 602-571-1864