Functions Of A Keyboard

Piano Pedals

The Soft Pedal (Una Corda: One String) is the left pedal and therefor played with your left foot. The Una Corda Pedal diminishes the timbre of notes that are played which creates a softer sound. 

Normally the keys of a piano are attached to two or three strings. This pedal shifts the keys and the hammers so that the hammer only hits one of the strings, so that it creates a softer sound. on an Upright piano, the hammer moves closer to the strings, so that it hits with less force and therefor creates a softer sound.

The Sostenuto Pedal is the middle pedal and is played with your right foot. This pedal is used to sustain certain notes on a piano while others won't be by hitting the notes you want to sustain and then press the pedal. the notes will continue to be played until you release the pedal. This happens because when you press the pedal, he hammers will be lifted from the notes you play on that moment.

The sustain Pedal (Damper) is the right pedal and therefor played with your right foot. When this pedal is pressed down, all the dampers lift up from the strings which causes all the notes you play to sustain as long as you keep the pedal down. This creates it to sound legato as the notes echo and overlap.

Grand Piano vs. Upright Piano

The soundboard in a grand piano is placed horizontally which projects the sound upwards and into the room. They are also bigger, which creates a greater volume.

The soundboard in an upright is placed vertically, at  the back of the piano. They usually place an upright against a wall, which limits the sound as the volume hits the wall before bounces back. This creates less control over the sound.

The hammers on an upright piano hit the strings from the side. This limits the speed. The hammers on a grand piano hit the strings from below. This makes it possible to play notes with much more speed and repetition. Because gravity is in the grand piano its favour. Hammers on an upright piano hit the strings from the side, which works against gravity and therefor moves slower.

The keys of a grand piano are longer than the keys on an upright. That might not always be noticeable as the keys extend into the piano. Because the keys are longer, it is easier to press the black keys and in between the black keys as they are closer to the centre of the keys. It also gives a pianist more control over playing. On an upright piano the keys are shorter, which makes it more difficult to press the black keys and in between the black keys.

Parameters with the keys of a midi keyboard

Velocity is the volume of the notes that you play. This is controlled by the pressure you put on the key. When you press one of the keys softly, the volume will be lower than when you press it hard. 

Pitch is the ordering of sounds that you play. This is controlled by what key you play on the keyboard. A midi keyboard usually has four octaves. If you play a key on the lower end of the keyboard, the pitch will be lower than when you press a key higher up the keyboard. 

Duration is how long the notes last. This depends on how long you keep the pressure on the key. The moment you release the key the note will stop.

Timing is in what speed or rhythm you play. If you press a key very fast the notes will be staccato and repeated very quickly after each other, but when you press them slower, the notes will be legato. 

Sustaining pedal on electric keyboard

First of all, the sustain pedal is not attached to the keyboard, it has to be plugged in. When you use a sustain pedal on an electric keyboard, the sustain pedal sends a signal to the keyboard which tells it to sustain the sound for as long as you keep the pedal down. While on an grand piano, all the dampers lift up from the strings which causes all the notes you play to sustain as long as you keep the pedal down.
As it is not a natural process for an electric keyboard, the notes will sustain shorter than on a grand piano. With the grand piano the vibration of the strings can go on for a long time, where with the electric keyboard they won't.

advantages/disadvantages of shaping midi data using a keyboard

When you use a midi keyboard, you can create a much more precise piece as you can control all the parameters, for example timing and velocity. With a real piano this is a lot harder as you can not change anything, except for the volume of the entire piece. Another advantage is that you can use a lot of different sounds on a midi keyboard. All the different kinds of pianos are programmed in there, whereas a real piano can only create one sound.
However, a big disadvantage of a midi is that it does not contain as much emotion as a real piano. Sometimes the tiny mistakes and adjustments are what make a piece special. Another disadvantage is that a midi keyboard sounds a lot faker than a real piano. After all, the sounds on a midi are recordings and will never sound as good as a real piano does.