How to Build and/or Buy a Cheap Good Quality Music Keyboard

28 March, 2013
How to construct a high quality music keyboard, starting with an iPad or an iPhone.

In the Musical Instrument Shop

If you walk into a musical instrument shop, and you say that you want to buy a cheap good quality keyboard, the salesperson probably won't ask you: "Do you already own an iPhone or an iPad?"

And even if you tell the salesperson that you own an iPhone or an iPad, he or she may not do anything useful with that information.

So I will tell you what you need to know:

What that means is, you don't need to buy a whole musical keyboard, you just need a midi-keyboard/controller that you can plug into your iPhone or iPad.

So, what do I need?

To make a playable musical keyboard out of an iPhone or iPad, you need the following six items:

My own current setup

How much will it cost?

The exact cost will vary, depending on what you already have and what you decide to buy. To create an iOS device-based music keyboard from scratch, prices in the US are roughly as follows:

If you already have an iPad, or an iPhone, that's about US$340. Including the iPad it's US$840, which is more, but then you can use the iPad for other stuff as well.

Apart from the cost, there is a more general advantage to having a mix-and-match system, which is that you can easily swap out individual components. For example, I recommend one particular midi-module app, but who knows what other apps may be available in the future. And you might want to experiment with specialised software-synth apps, none of which cost that much. Also, if portability matters, several small things can be easier to carry round than one large thing.


For each of these six items, there are choices you can make. I will go over your options for each item.

The iOS device

I own an iPhone 5 and an iPad 1. SampleTank works with both of these devices, but I have observed the following limitations:

It follows from these limitations, that if you don't already have an iPhone or iPad, and you are serious about making good music, you should buy the latest iPad (the iPad 4 aka the iPad with Retina display). CPU power matters (so don't buy an iPad mini, which is less powerful than the iPad 4), and so does screen size.

16GB of memory is probably sufficient – SampleTank uses up 1 Gigabyte, but at the moment it is unlikely that all the other music apps you buy put together will use up even 1 Gigabyte in total. And raw audio doesn't use up so much space – a CD is about 0.8GB of raw digital audio, and that's about 60 minutes of music. But you can get more memory if you really want to.

The Midi-Module App

SampleTank is by far the best midi-module iOS app available. (As far as I know – one app I haven't been able to try is Cubasis for iPad, because that requires iPad 2 or later.)

With midi-modules, the more instruments to choose from, the better, because probably you will only like some of them. Compared to most iOS apps, SampleTank with the full SoundPack is an expensive app. Compared to dedicated musical equipment, the cost is trivial. So just buy the full Sound Pack and be done with it. (You can also register with IK Multimedia, and get yet another 4 instruments. I'll let you decide if that one is worth it.)

There are some limitations with SampleTank that I have observed, including the following:

Despite these limitations and annoyances, if you want something where you can just sit down at a keyboard and play nice-sounding music on your iPhone or iPad, SampleTank is the app that you need.

And a warning: beware of judging instrument sound quality from playing directly on the screen. The SampleTank screen keyboard does not have any attempt at touch sensitivity built in, so instruments like piano and guitar sound very "flat" or "monotonous". (Some instruments are OK without touch sensitivity, especially some of the string sounds, and the "Breathy Flute".) Whereas GarageBand is actually touch sensitive on the screen keyboard. This is very clever of Apple to make that work, but it can mislead you into thinking that GarageBand's piano sounds are better than those in SampleTank (or iGrand Piano), but they don't sound so good when compared from an actual touch-sensitive keyboard.

Another limitation is that SampleTank doesn't do keyboard splitting, and if your keyboard doesn't do splitting (which mine doesn't), then you need some additional software to do this, and that software is MidiBridge. If you also want your sustain pedal to work on both parts of the split (and you probably do sometimes), you also need another free app FreEWI, and you have to do some tricky things to get it all working (which I might explain in a separate blog post).

(Technically, a keyboard split is when you split the keyboard, and notes in the upper part send on one midi channel, and notes in the upper part send on a different midi channel. SampleTank can receive keyboard splits, because you can choose up to four instruments, and assign each instrument to any one of 16 channels. But it can't split an incoming keyboard connection, which is why you need the additional software.)

Honourable Mentions

Touch-Sensitive Midi-Controller or Keyboard

There are many midi keyboards that you can use with the iPhone or iPad. You may even have an old midi keyboard lying around the house that you can use (but you might need to purchase a separate adaptor, especially if your old keyboard has the old-style midi sockets).

I decided to buy the Line6 MobileKeys49, because it was advertised to work directly with iPad and iPhone, and I knew I was going to buy myself a new iPhone.

However, if you have or intend to buy a newer iPad, then this doesn't matter so much, and there is a larger range of keyboards you can choose from.

Whatever keyboard you buy, it must absolutely be touch sensitive. Some "instruments" sound OK without touch sensitivity, but for anything like guitar or piano, touch sensitivity is essential.

You may also want to get a weighted keyboard, in which case the total solution may not be so "cheap" anymore, as you can sometimes buy a complete digital piano for about the same price as a weighted midi-controller.

Cabling between Keyboard and iPhone/iPad

The MobileKeys keyboards come with their own 30 pin connectors. If you have a newer iPhone or iPad with the "Lightning" socket, then you will still need to buy a 30-pin to Lightning adaptor (from Apple, and it's not the world's cheapest cable adaptor).

Most modern midi keyboards do USB, and to plug that in you'll need an Apple Camera Connection Kit, which is a fancy way of saying a USB adaptor. (Unfortunately the USB adaptor that comes with your charger does not work for this purpose.) And if you have a Lightning iPhone or iPad, you'll need an extra adaptor for that (because as yet Apple does not make a Lightning-specific "Camera Connection Kit").

If a device works with a PC, it probably also works with an iPad, but it's best to be sure and buy something that advertises iPad-compatibility on the box.

Typically, if a device requires more power than an iPhone can supply, you may get a message like "This Accessory is Not Supported by iPhone". Which is not the world's most informative error message. (Apple is like this sometimes: "We are so user-friendly, we don't want to overburden the user with too much information when something goes wrong.")

Sustain Pedal

Sustain pedals plug into the actual keyboard, and the interface for this is extremely standard. Which actual pedal you choose is entirely up to you. The physical action and response does vary between different types of pedal, so it's best to actually try them out. Also there a different styles of pedal, like simple flat boxes, and pedals that are shaped like standard piano pedals.

Computer Speakers

For computer speakers you just need reasonable quality stereo speakers (because music apps do output sound in stereo), perhaps with a bass woofer. Computer speakers powerful enough for a home computer don't cost that much anyway, so just choose whatever works for you.

I will say that the sound coming out of the iPhone or iPad speaker is not loud enough to properly hear the music your are playing, although the volume is plenty loud enough if you use headphones.

Update (14 April 2013): the latest version of SampleTank now supports AudioBus, so I have edited sections of the article where I described recording options.