Initially, the concept of MIDI can be confusing, but hopefully in this tutorial you will realise that MIDI is pretty simple and has many uses.

What is MIDI?

Many people know that the MPC is a sampler capable of recording audio from a variety of sources. But in reality, sampling is perhaps the weakest part of the MPC - the main use of an MPC is its sequencer.

What is a sequencer? It's a device for recording data about musical events, rather than audio. With a sequencer, you do not record the actual sounds from the performing instrument, you simply record note data, which can consist of pitch, volume, length etc as well as the timing of that note in relation to other notes. These instructions can be used to play the sounds from any compatible sound source (such as a sound module, another sampler, a keyboard synth, etc).

So, an example of sequencer information in plain English would be something like this:

"At the start of Bar 2, play a low C note for exactly one bar, at a volume of 50"

This information is what your MPC will store in its sequencer (but in a different, more mathematical format!). But as you can see, the above information is very generic and is certainly not audio! So, to make a sound from this information, you have to send this information to a piece of equipment that is capable of reading this data and knowing that this data is an instruction to play a 'C note'.

A standard form of information transfer was developed that allows instruments and sequencers to talk to each other - it's called MIDI. MIDI stands for M usical I nstrument D igital I nterface. It's very important to understand one thing - Midi does not carry audio, merely instructional data .

The MPC can transmit and receive MIDI signals. It can also record incoming MIDI signals in its sequencer. Once that data is saved into the sequencer you can hook up any MIDI instrument that is capable of emitting sound and get the MPC sequencer to 'command' it play the notes saved in its sequencer.

So why do we need MIDI? Well, let's look at synthesizers and sound modules. If you have a synth, it will have a built in keyboard so when you hit a key, a sound will play depending on the sound patch you have selected. But if you have a sound module, you do not have a keyboard built in, you have to control the built in sounds using a MIDI controller.

The most common MIDI controller will be a MIDI control keyboard. These keyboards do not have sounds inside them; all they do is transmit MIDI signals. When hooked up to a sound module, it's these MIDI control signals that tell the sound module which note to play. So, press a C note on the control keyboard and it sends a MIDI message to the sound module to play a C note and then the sound module outputs an audio sound in the key of C.

If you hook up the control keyboard to your MPC and press a C note, your MPC will receive this MIDI data and record it to its internal sequencer. At some point later, you could then connect your MPC to a sound module and press PLAY on your MPC. The recorded MIDI information will be transmitted to the sound module and the C note will be played (out of the sound module audio outs, not the MPCs!). Now the MPC is acting like a MIDI controller. At no point in this situation does the MPC output any audio sounds - only the sound module will output sounds - remember, MIDI just carries the instructions (sorry, but this is a misconception that arises A LOT!).

What About Internal Samples?

The MPC can be set to either play external sounds via MIDI connections to sound modules, or you can sample (or load) sounds into the MPC and use the sequencer to play these. In fact you can have the 'best of both worlds' - you can use you MPC to play MIDI devices and play internal samples. So for example, you can have a sampled drum loop playing that is stored inside the MPC and you can have a bass line being played by a sound module controlled by your MPC.
We'll describe all this in much greater detail in the forthcoming tutorials.

Main MIDI Situations with an MPC

There are several uses of MIDI in relation to our MPC and we shall look at the main ones now. Do not worry if this sounds a little confusing - you can always refer back to this section when you need it later. Before we look at the more complex uses of MIDI, we'll first look at a way we can use MIDI signals to control samples that we've loaded into our MPC.

Controlling the MPC pads with a keyboard

This is the simplest MIDI set up. As I'm sure you know, your MPC is a sampler, which means you can sample sounds into it and play those sounds by pressing the rubber PADS on the right hand side of the machine. But, we do not have to play these internal MPC sounds with the PADS - we can use a MIDI controller keyboard instead. As I've already mentioned, a controller keyboard is simply a keyboard with no sounds inside it that is used to instruct sound modules to play their internal sounds. Well, in this case, our MPC can be considered a 'sound module' - i.e. it's a machine capable of receiving MIDI instructions, and these instructions will tell it which internal samples it will play.

Set-up is simple. All you do is connect one end of a MIDI cable to the MIDI out port of the control keyboard and the other end to the MIDI IN port of the MPC (I would connect to MIDI port 1 by default).

Notice in the above diagram that there is no audio connection to the MIDI control keyboard, there's only a MIDI connection to the MPC. In this situation, the only sounds will come from the MPC audio outputs (remember to load some samples in first!)

When you play a key on your keyboard, the note you play has certain properties - the note has a key represented by the 'MIDI note number', it has a volume (or loudness) represented by 'velocity' and it plays for a certain length of time - this is represented by its length. There are other properties that can be represented but we don't need to worry about those at this stage. All this information about the note you are playing on the control keyboard is sent down the MIDI cable to your MPC and can be stored or recorded into the MPC’s sequencer (as we shall see in later tutorials).

So, as long as the key you press on the keyboard corresponds to a sampled note in your MPC, your note will be played and will come out of the MPC audio outs. We'll look at how to assign sounds inside your MPC in a later tutorial.

Connecting up a keyboard with sounds (synthesiser)

If you have a keyboard with its own sounds, like a Korg Triton for example, you can still control the MPC samples as you did in the last example. This is because any synthesiser keyboard will transmit MIDI information. Just remember that the main difference here will be that your keyboard in this situation can also emit sounds itself - so make sure you turn off the synthesiser's volume control, otherwise you'll not only hear the MPC internal samples, but also the synth's sounds as well!

The main thing I want to show here is that a synth not only has a MIDI out, it also has a MIDI IN - hence it can not only send MIDI information, it can also RECEIVE it. Equally, our MPC not only receives MIDI information, it can also TRANSMIT it. This means that we can send a MIDI information signal to our synth from our MPC and this signal can (amongst other things) tell our synth to play a particular note. How do we send a MIDI signal from our MPC? Well, the PADs all have a unique MIDI note number so when you press a PAD, it's the same as pressing a key on a MIDI keyboard. For example, PAD A1 is by default MIDI Note 37 - if a MIDI synth is connected to your MPC and you press PAD A1, it will play MIDI note 37 (C#) in our synth.

This time, as well as connecting the keyboard MIDI out to the MPC MIDI in, you connect the MPC MIDI out to the keyboard MIDI in. This is called the MIDI 'handshake'.

So, press a PAD on the MPC and a MIDI instruction travels from the MPC MIDI out to the synth MIDI in. Upon receiving it, the synth plays the appropriate note which in turn is outputted as audio through the synth's audio outputs.

Equally, you could press a key on the synth and this will transmit a MIDI instruction to the MPC. Upon receiving this instruction, the MPC could play an internal sample (should one exist at that MIDI note number) which would be outputted out of the MPC audio outs (if connected).

MIDI channels

For the MPC to play the sounds of a keyboard we need to understand MIDI channels. Each MIDI cable is capable of sending data over 16 individual channels. In our keyboard, let's say we assign a bass patch to MIDI channel 1, and a piano patch to MIDI channel 2. Now, in our MPC, let's assume we have a track in our sequencer and it contains one track of note data. If we assign that track to MIDI channel 1, the MPC sends data through the MIDI cable to our keyboard on channel 1 only, and you'll hear a bassline played from your keyboard as this was the sound assigned to MIDI channel 1 in our keyboard.

If we then change the MPC track to output on MIDI channel 2 instead, we will not hear the bass sound anymore, instead we will hear the sound our keyboard has assigned to MIDI channel 2 (that was a piano sound).

If we add a new track to our sequence and assign this to channel 1 (along with the track on channel 2), we'll hear both a bass line and piano at the same time. This is because our MIDI out tracks of note data in our MPC, we could assign each track a unique MIDI channel number (1 to 16) and hence be capable of instructing our sound module to play 16 different sound patches (as long as we had assigned a sound patch to each MIDI channel within our sound module).

We'll look at how to set MIDI channels in your MPC and the specifics of recording MIDI note data
later in this book.

Hooking up a sound module and using a keyboard to play its notes into the MPC

Let's say you have a sound module like a Roland XV2020. It has no keyboard so you need to play its notes with a control keyboard.

In the above picture, the control keyboard sends MIDI information to the sound module which in turn plays the note as audio out of its audio outputs.

So how do we record a MIDI performance of these sounds into our MPC? Well, this time we need to set up a MIDI chain. As before, the keyboard controller MIDI out goes into the MPC MIDI in, but this time the MPC MIDI out goes into the module MIDI in.

Again, make sure you have your MIDI channels set properly and the audio out of your module connected to an amplifier. Now, when you play some notes on the keyboard, it sends info to the MPC via the MPC MIDI IN, and the MPC then sends this same information via the MIDI OUT to the module's MIDI IN - and you should hear some sounds from the module - at the same time, if you se your sequencer to record, you'll be able to record all the MIDI information into your MPC.

Adding another module

You can add as many modules to the above set up as you like. Simply connect the MIDI thru from the first module into the MIDI in of the next module and the MIDI thru of that module into the MIDI in of the next module. Just make sure you set each module to a different MIDI channel. So let's say to have a JV1010 and a Korg Electribe hooked up, it would look like this

From here, you can see that when you play the keyboard, the MIDI signal is sent to the MIDI IN of the MPC. That same signal is then sent out of the MPC MIDI OUT into the JV1010 MIDI IN.
That signal is then passed on via the JV1010 MIDI thru to the Korg MIDI IN. But to hear our modules we have to set the correct MIDI channels first.

Setting the Channels

Set the JV1010 to MIDI channel 1, and the Korg to channel 2. When you want to record a sound from the JV, set your keyboard to MIDI channel 1, and set the track you wish to record on your MPC to channel 1 also. When you wish to record the Korg, simply set your keyboard MIDI channel to 2 and select the MPC track you wish to record on to channel 2 also. Upon playing back your sequence, your MPC will send messages to both MIDI channels 1 and 2 and you will therefore hear both modules at once (as long as both modules are connected to an amp via a mixer).

Hooking Up and Synching to a Multi Track Recorder or a Computer