Keyboard instruments come in a variety of shapes and sizes, and while the basic layout of the keys remains the same, their size, weight and feel varies significantly between instruments.
This guide will help you pick the best keys for your playing needs.
1. Keyboard Options
The three main factors to consider are the number of keys a keyboard has, what size they are, and how heavy they are to play.
Number of Keys
Keyboards range from 25 or fewer keys right up to 88 or more keys, usually on a single tier keyboard but sometimes, in the case of an organ, in two or more tiers.
Digital pianos, emulating their acoustic cousins, often have 88 keys, although 76-key and 73-key models are also quite common.
Workstation and controller keyboards often also feature a full 88 key keyboard, although they range considerably and include 2-octave (25 key), 4-octave (49 key), 5-octave (61 key) and 73/76-key.
Less expensive home keyboards often come with 61 keys, though larger and smaller versions are available.
Size of Keys
The size of keys are usually described in relation to that of an acoustic piano or an organ.
Full-sized keys are found on digital pianos and a variety of other synths, workstations and home keyboards.
Mini-keys are often found on very inexpensive keyboards designed for children, although some ultra-portable controller keyboards may also incorporate them. Generally they are smaller in both width (side to side) and length (front to back) than full-size keys, and some larger adult fingers may find it difficult to play distinct notes.
Hybrid keys (my term) may have the full width of piano keys but a reduced length.
Shape of Keys
White and black keys may differ in shape between various keyboard styles and manufacturers.
Digital pianos generally emulate the key shape found on an acoustic piano.
Other keyboards with full-size keys may have more rounded or angled keys.
White keys may have a full front to them, akin to a piano, or just a few millimetres, like an organ.
Weight of Keys
A key’s weight refers to how much physical resistance it offers when a player’s finger strikes it. Key weight varies significantly between different types and manufacturers of keyboard, and even across an individual instrument.
Digital pianos may have a fairly heavy uniform weight of key across the entire range, or they may simulate an acoustic piano by ensuring the lower (bass) keys have a heavier touch than the higher (treble) keys. Other workstation and controller keyboards may also have piano-style keys like this.
Organ/synth action style keys are generally light to the touch, with no difference between upper and lower keys. Semi-weighted keys offer a weight somewhere between weighted and organ/synth.
There is no standard weight for any key type, even on different keyboards from the same manufacturer. One thing to bear in mind is that some keyboards offer the user the ability to change the weight of the keyboard. In fact, this alters how sensitive the keys are to the player’s touch. It does not change the physical weight of the keys, or the strength required to play them.
Some weighted key keyboards feature an internal mechanism very similar to a piano, including the hammers, whereas others employ some kind of resistance to produce a noticeable weight in the key.
Finish of Keys
Keys may come in a variety of finishes. Digital pianos and higher-end workstations will often simulate the feel of acoustic piano keys (of course, ebony and ivory are no longer used). The keys on most keyboards have a slight gloss/sheen to them. Expensive keyboard instruments may incorporate material designed to absorb moisture from the fingers.
Velocity Sensitive Keys
The keys on all but the cheapest keyboard instruments are velocity sensitive. That is, the instrument responds to how hard a player hits a key, often by making the sound louder and possibly altering its timbre, much as a piano does. There is often an option to turn this feature on or off, or some voices such as organs may not register it.
Aftertouch Sensitive Keys
More expensive synthesiser and workstation keyboards feature keys which can transmit aftertouch information. That is, once the key has first been struck, additional pressure on the key can trigger further effects such as vibrato, pitch bend, and so on. It requires different hardware to be built in to the key bed, under each key, together with the operating system to process it.
Some keyboards offer polyphonic aftertouch. That is, the keyboard can recognise and respond simultaneously to varying pressure on each key currently being depressed. Other keyboards will only respond to the aftertouch on one key (which may be the first or last key pressed) no matter how many keys are held down. The first offers greater sound altering possibilities while the second may offer a more uniform effect. The latter style is more common.
2. Choosing a Keyboard
The theory is all well and good, but what type of keyboard should you choose for your needs?
If you want an experience as close to an acoustic piano as possible, then you will want fully weighted, full-size keys. Generally, the more you pay for an instrument, the better its key action will be. Aftertouch is not a consideration, and it won’t be available on most (if any) digital piano keyboards. Best suited for piano-intensive music including classical and jazz.
If you’re looking for ease of playing synth or organ parts, a non-weighted organ/synth style key weight will most likely suit you. It can be quite difficult playing fast jazz organ parts on a weighted keyboard. Best suited when piano realism isn’t a top priority.
Semi-weighted keys provide the best of both worlds — or a compromise, depending on how you look at it. A semi-weighted keyboard with a good, solid action can be a good all-rounder, heavy enough for ample expression in piano parts but light enough for fast organ/synth solos and the like.
You will generally pay more for a keyboard equipped with aftertouch, but it can be a very useful and intuitive controller for synth players. It’s generally found on higher-end synthesisers and workstation keyboards.
Size of Hands
If you’re buying a keyboard primarily for a very young child, an instrument with mini keys may be your best option. Otherwise, full-size keys are generally the way to go unless you are simply using the keyboard for step input or small pieces of live playing.
Controlling Other Equipment
Your choice of key type may be dictated by whether you are using it as a standalone keyboard or whether it will control other sound sources.
This can also be a valuable consideration if you like a particular model but aren’t mad keen on its keyboard. Many keyboards can be controlled from a different keyboard, via MIDI. It may also be possible to get a sound module (has no keyboard) version of the keyboard you are interested in, or even a software emulation of it.
This may not be so helpful for touring/gigging musicians, but for those primarily studio-based it’s a definite consideration. You may well end up with a really great keyboard which you can use to control a number of other devices.
Generally, keyboards with a greater number or weight of keys will be heavier, although other factors must be considered such as whether it has built-in speakers.
If you are frequently on the road and need to travel light, smaller and lighter keyboards may be what you need. If you need a decent piano and can compromise a little on size and weight, a semi-weighted 76-key keyboard is a good choice.
3. Testing it Out
Purchasing instruments online can be a great time and money saver but sadly it doesn’t offer the possibility of testing out different keyboards.
Even if you know the basic specification of an instrument, you can only really know how it plays by getting hands-on time with it.
Keyboards vary, even between models from the same manufacturer, due to price and changes/improvements in construction style. If you are able to, I would recommend visiting a music shop and trying out the keyboards you are interested in.
Our keyboard finder database lists basic specifications for a range of digital pianos, keyboards and synths, including the number of keys and an indication of key weight.