Your teacher has informed you that it is time to upgrade your instrument because you have outgrown your 88 key digital piano. How does that happen? Is it possible to “outgrow” a piano? They both have the same amount of keys, and your digital piano has weighted keys, just like an acoustic, so why the need to upgrade?
To answer simply, there are two main areas that make the biggest difference: dynamic touch and dynamic tone.
The concept of touch for any keyboard is fairly straightforward: you push on the key and it makes a sound. However, for acoustic pianos the reality of touch is much more complicated.
Think of acoustic piano keys like a see-saw on a playground. The idea of balance is realized fairly quickly on this childhood device – the weight becomes easier to push if you were furthest away from the centre. Piano keys are exactly like that. When it comes to upgrading from digital piano to acoustic, one of the most significant changes is a better balance point.
Take a look at the following diagram with the two different pressure points marked in red.
Digital pianos have significant touch discrepancy. With acoustic pianos, the balance point distance is substantially further. This creates a more even touch weight from front to back of the key. One sign of a great piano is low variation between the front and back of the keyboard.
Another significant distinction between acoustic and digital is the idea of dynamic touch weight. Take a look at the side cutaway of the upright piano.
Labelled is the hammer which rotates towards the string. This rotational inertia, similar to a hammer or an axe – gives a very different sensation than the static weight of a digital piano. A digital piano simply raises or lowers lead weight up and down. It doesn’t have a multiplied force when played louder and subsequently, there is no dynamic force on a digital piano.
Ever so slight and yet perceptible is the idea of resistance in part by springs in the action. In an upright piano, for example, the pivot point of the hammer we just spoke of not only has rotational inertia but it’s also spring loaded. The spring resists the hammer and at low pressure, low volume, you can feel the spring engaged. As the hammer moves closer to the piano strings, the tension of the spring also increases, causing more pressure to return the hammer to reset.So why upgrade? Longer keys mean better balance from front to back of the piano keys. The rotational inertia gives dynamic touch changing the feel as you play soft to loud. And finally, the spring loaded joints aid the reset. All of these work collectively to define the touch of a piano. When you compare that to a digital piano where the touch weight is simply raising or lowering a lead weight on a see-saw, the difference is significant. In addition to these touch elements, traditional pianos also have adjustable parts to refine the touch components as well.
When it comes to upgrading from a digital piano to an acoustic piano, there are also 2 sound concepts to be mindful of: The first is the continuous flow of sound which we commonly refer to as analog. The second is dynamic timbre referring to how the sound quality changes with dynamics and volume.
First, let’s look at the comparison between acoustic sound and digital sound. The acoustic piano creates sound by a hammer striking a string. The subsequent vibration is amplified by the soundboard into audible tones.
How do digital pianos make sound? Digital pianos don’t actually create sound. They simply play back a digital recording of a real piano. But digital sound and live string resonance are different. Digital sound is made up of many frames per second to give the illusion of continuous sound. Natural vibration of a string is a continuous waveform that we perceive differently, and so, digital pianos will always and only be a facsimile of a real piano.
The second concept of sound is the idea of dynamic timbre. Just as acoustic piano touch is dynamic and changes with volume, so too piano tone or timbre changes character with volume. As the hammer strikes the string at soft to loud volume levels, the piano hammer felt is compressed differently. Depending on volume, other sympathetic tones of the piano also ring. An acoustic piano is not a matter of simply raising or lowering volume but rather, the piano tone changes color with dynamic touch.
There’s this common school of thought “Let’s get a keyboard and if they stick with it, we’ll get them a real piano”. Do children learning the piano ever fall in love with the tone of a keyboard? Have we lost the connection to analog – this continuous vibration of the strings? Does it resonate with us the same way? Have we given them a handful of colours and limit the pure enjoyment of limitless expression?
I believe these are the thoughts and intentions behind teachers wanting more for their students. When they speak to parents about upgrading, it’s not about some high-brow approach to narrow minded Classical performance. It’s the desire to connect with a more fundamental, more organic way of expression in music – one that is beautiful and lovely. So the next time the teacher encourages you to look at a traditional piano, they’re really saying ‘let’s go deeper, let’s create music, and let’s experiment with touch, with tone and experience music to its fullest extent.”
Article from Piano Price Point