The Experiment

I am conducting an experiment to determine which is easier to play: the Linear Isomorphic Keyboard (LIK) or the traditional keyboard (TK).

The Plan

To compare the two keyboards, I'm going to practice the same content for the same amount of time on each keyboard. I will be recording the practice sessions and keeping track of my proficiency with each set of exercises. By keeping the practice routine consistent between keyboards, I should be able to compare their playability.

Defining Playability

I define playability of an instrument as the ease of performance with a given set of content. 

Playability can only is dependent on the content that is being played. A saxophone would have trouble playing multi-part harmonies in piano music, and a piano would have trouble bending notes like a saxophone. Both instruments have a plethora of music they can play with ease, but they often can't play music written for other instruments.

Thus appears the first confounding variable of this experiment: the content of the practice sessions. I will be playing music written for the traditional keyboard, not for the LIK (there is none). Performing music written for the instrument you are playing provides an advantage in playability. We can see how this advantage maniests in both aspects of playability. 

Assessing Playability

For a given set of musical content, playability can be measured by the presence of technical limitations and the rate of improvement. 

Technical Limitations

Technical limitations are aspects of an instrument that make a musical pattern impossible to play. Saxophones are monophonic, meaning they can only play one note at a time. When attempting to  play polyphonic music, this is a technical limitation. The keyboard I practice has a range of five octaves, which is a technical limitation when playing music that goes beyond that range. 

The more technical limitations reduce the playability of an instrument. If the LIK couldn’t play any music written for the TK, it would be unplayable, and would not warrant comparison.

I don’t expect to find technical limitations for the TK because most of the exercises I am playing were written for the TK. However, I will be looking for technical limitations when assessing the LIK.

The Rate of Improvement

Imagine an instrument with no techincal limitations. It could play any sound imagineable, from a Stavinsky sonatas to whale songs. This sounds like quite the playable instrument. But if it took 1,000 hours to learn to play a note (and 10,000 for a whale moan) it would be unplayable.

Now imagine two instruments, A and B. They are exactly the same, save for one fact: people learn to play A twice as fast as B. This would make instrument A more playable than instrument B.

The rate of improvement is the second consideration when assessing playability of instruments. Technical limitations answer the question, "Can I play it?" The rate of improvement answers the follow-up: "How long does it take to learn?"

Playability is dependent on the music, and the rate of improvement is no exception. Hanon's finger exercises are largely in the key of C, which is far easier for the TK than it is for the LIK. Because of this, expect the LIK to improve slower (and thus be less playable) when assessed with Hanon.

Comparing Playability

I am going to practice the same content on both keyboards for the same amount of time. The keyboards are similar quality as they are both Midiplus i61 keyboard controllers. I made the LIK by replacing all the keys with black keys and lengthening them with 3D printed extensions.

Controlling the quality of the keyboards and the time practiced is simple. But controlling the content of the practice sessions is much more difficult.

Controlling the practice sessions

I made a practice curriculum that both keyboards share. The material is be broken down into three domains of musical prowess: fundamentals, sight reading, and playing by ear. Within these domains there are sets of exercises. For instance, Hanon's finger exercises is a exercise set within fundamentals.

Each keyboard will practice the sets of exercises for the same amount of time. But within that exercise set, the specific exercises they play are left to my discretion. 

I could choose to keep the practice sessions exactly the same between keyboards, but it would be unfair to one of the keyboards. One instrument would get a custom tailored practice session while the other would have to practice content far to difficult or easy. For instance, if I practice the first Hanon exercise at 60 bpm for 20 minutes on the LIK, I shouldn’t force the TK to do the same. The TK could have a much easier time with that exercise, making it a waste of time to practice for as long as the LIK.

I also could choose to have no shared curriculum and instead practice whatever I think to be best for that keyboard. This approach is flawed. It would be very difficult to measure and compare rates of improvement, and the quality of the exercises would be a confounding variable.

My choice is the Goldilocks option. It isn't too restrictive, as it allows each instrument to improve at its own pace. But the shared curriculum also lets me compare and measure improvement.

You can find out more about the curriculum and the reasoning behind it here.


By the end of the experiment, I will have data that shows how long I played each exercise on each keyboard. It will show what difficulty I can play any given exercise at, and how much practice it took me get to get there. I will be able to measure my rate of improvement on each exercise set, and along the way I will identify technical limitations. You can see this data live here.

With this data, I will come to a conclusion about the playability of the two keyboards across all domains of musical expertise.

The Flaws

To have any confidence in the results of the experiment, I need to be aware of its shortcomings. There are plenty of flaws that are substantial enough to deserve recognition.

The study is not blind and only has one biased participant (I think the LIK is awesome). I don’t know how much of my improvement on the LIK will be a result of transferable skills on the TK or vice versa. As I have mentioned, the content I am practicing was written for the TK, not the LIK. Because of this, they might not have the same beneficial impact for the LIK.1. Also, at the outset of the experiment, I will be better at the TK than the LIK. I have played the piano on and off since I was seven, while I played the LIK for no more than twenty minutes before the first assessment (I couldn’t resist).

Another confounding factor will be my ancillary musical skills, as they can limit my the performance of both keyboards. My inability to play a scale quickly might be due to my dexterity rather than my familiarity with the keyboard. My ability to play either keyboard by ear is limited by my ear. It might be easier on one keyboard than the other, but if I can’t remember the notes I heard, neither keyboard will do well.

The varying difficulties of increments can be a confounding variable. An increment that increases tempo could be easier than an increment that increases the largest interval. This confounding variable is nullified if both keyboards are able to complete the increment. Then we will still be able to compare rate of improvement of the keyboards, even if some increments take longer than others.

If it is a difficult increment to complete, we will still be able to see the difference in the time it took to complete the interval between keyboards.

The last confounding variable is the benefit of transferable skills. While practicing Hanon, I am going to be practicing a lot of C major patterns, and this will benefit my ability to play the C major scale. It could look like I am improving without much practice, or this improvement could go unnoticed until I revisit it. 

In Conclusion

I have defined playability as the ability to perform a given set of music, measured by technical ceilings and rate of improvement. I have structured the experiment so the keyboards share a curriculum, but have flexibility over what they practice. This should keep the practice sessions fair, flexible and measurable. Despite the experiment's flaws, I think that the results of this experiment will still be meaningful. I hope that the results can give insights on the playability of isomorphic keyboards and encourage more experiments.

  1. Long-tones is an exercise for wind instruments, in which the instrumentalist sustains a note to improve their tone quality. This exercise is not useful on the piano as pianists do not have control over sustained tones. This is an extreme example, but it illustrates that exercises are not always equally beneficial for all instruments.