Digital Pianos and "POLYPHONY" - What is it? REPORT

UPDATED REPORT: September 1, 2019 - Digital Piano Polyphony - Report - The topic of "polyphony" in a digital piano and what it means is actually a an interesting but yet mostly confusing subject to many people but one that is good to understand, especially if you're looking to purchase a digital piano. Since digital piano companies make an effort to publish the maximum number of "polyphonic notes" that their different models can produce, then it's important to understand why they talk about "polyphony" and why it might be something you may want to consider when shopping for a new or used digital piano.


My name is Tim Praskins and I have been playing digital pianos, organs, keyboards, and guitar for many years (over 40) since I was quite young because my parents got me into music lessons early, and I thank them for that. My first instrument was guitar (I played in bands), my second instrument I learned was piano but I dropped out early because I was young and I didn't enjoy it because I thought it took too much work to learn to play. My next instrument was organ and I learned to play many different organs very well.  Finally I played piano again and this time I loved it because I was playing fun things on a digital piano and could practice in privacy with with headphones. I learned about piano polyphony memory in digital pianos & keyboards a long time ago because it became important as I progressed in my playing skills and now I am an expert at it. Polyphony which is phonetically pronounced "pol-if-a-knee" is the ability of the instrument sounds and notes you are (at any moment) playing on the piano to be heard all at the same time without interruption or note "dropout" including any drum patterns, chord arrangements, and sustain pedal being used.

Casio AP470 piano
Casio AP470
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. However, most people do not play that way with all those things at one time so polyphony power needs are relative to how well you play, the type of music you'll be playing, the way the acoustic piano sound was sampled on that piano, and how many sounds and features you would use at one time along with how you record them if you like to use those kinds of features. So the whole "polyphony thing" can be much more complicated than one might think because the need for a lot of polyphony is relative to how well you play and what your musical needs are.

Yamaha digital grand piano
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 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. I used to be:) 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'll ever use and this type of thing (having way more technology than you'll ever use) is true of many electronic devices, 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.

Yamaha 88-note keyboard
Yamaha YPG535 - 32 note polyphony
Long ago when there was only 8 notes of polyphony in mono sound (I had a few of those digital pianos & keyboards) and you had two instrument sounds on (in a layer like piano & strings) at one time 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 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 instantly 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 I suppose it was better than nothing.

Kawai CE220 digital piano
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 complex songs with more sounds and better instrument sound realism without too much note dropout or sound interruption. 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 24 notes of polyphony (wow!) as well as another sound module (all the modules were rack mounts) with 16-notes of polyphony all connected (MIDI'd) together. 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 beyond "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 little 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.

Roland piano
Roland - 128 note polyphony
Now manufacturers have started to figure out how to put more polyphony memory and other ingredients (including more cool 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 they play, especially if they are playing piano music at a beginner 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 desirable and necessary.

Korg G1 Air digital piano
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 way more than enough note processing power even if you are at a very advanced playing skill level as long as you will not be recording multiple tracks of music with simultaneous playback of many stereo sounds and notes. Larger polyphony is really ultimately not that important with this kind of playing and recording in mind. 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. Roland and Korg digital pianos are great examples of 120 & 128-note polyphony respectively that can play without any loss of notes even at very 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 new 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 chips. 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 better piano sound as opposed to the other way around. The bottom line is that "polyphony" and how it effects the overall results of your piano playing is only part of the issue, only part of the piano playing experience. A certain minimum amount of polyphony power is needed (about 120 notes) 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.


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

11 comments:

  1. pretty interesting, best description i found on web, thanks.

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  2. good info! it is exactly what I was looking for. thanks!

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  3. About the YAMAHA P35... It has only 32 polyphony... So, would that be an issue? I plan on buying a digital piano and I was thinking about the YAMAHA P35, but I am very concerned about the 32 polyphony only... (I am more into classical piano music). For classical music, how would you classify it? Is it good enough?

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  4. 32 note polyphony is not nearly enough for more complex classical music and the P35 has a limited pedal decay time which is also a deficiency for classical music. I would suggest something else if you can afford it. You may contact me by email for more help and details

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  5. I am looking at the Roland hp 505 which has 128 I believe. Is this good enough for an advanced player?

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  6. Hi there,

    The answer to your question is not a simple one. Please contact me by email or phone if you're in the US, or just email if you are outside the US. If you are in the US please let me know where you live...your zip code would help as I like to know where people are contacting me from:. Thx

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  7. Hi Tim

    I am looking at getting a digital piano for my son who is working towards his Grade 1 exams. We have an old Yamaha PSR 292 keyboard at home, which does not offer weighted keys for his practice. I found a used Roland F100 for around £300. However as it is a rather old model, it only has 64 note polyphony. Would you recommend this piano?

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  8. 64 note polyphony would be OK but the F100 key action is not very realistic as compared to other digital pianos. However the F100 is certainly much better than PSR292 so it would be fine as long as the price is low. There is normally no warranty on used digital pianos so there is always a risk in buying used.

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    1. Thanks, would Kawai CN24 or Yamaha Ydp162 be a better investment? Which of the two?

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  9. Hi Tim,

    I am looking at a persistent solution for a stage/recording piano, for years to come. I was looking at PX 350 (~ USD 670) that has 128 notes polyphony. So I was like wondering, will it be seriously wiser to pay an extra ~ USD 400 to get, say a PX 5S that has 256 notes polyphony (disregard all other factors).

    What do you recommend?

    P.S. PX 850 is not really an option for me as it doesn't have on board speakers.

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  10. I'm a beginner... beginner. I'm looking at an older Yamaha that is in good condition with 16 polyphony. Am I going to be disappointed with that, to start with?

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