Yamaha PSR-2100 Owner's Manual - Page 159

Using Your PSR-2100/1100 with Other Devices The "controller" and "tone generator" in the illustration above are equivalent to the piano in our acoustic example. Here, the player's performance on the keyboard is captured as MIDI song data (see illustration below). In order to record the audio performance on an acoustic piano, special recording equipment is needed. However, since the PSR-2100/1100 features a built-in sequencer that lets you record performance data, this recording equipment is unnecessary. Instead, your digital instrument - the PSR-2100/1100 - allows you to both record and play back the data. Tone generator Sequencer Keyboard performance (MIDI data) However, we also need a sound source to produce the audio, which eventually comes from your speakers. The tone generator of the PSR-2100/1100 fills this function. The recorded performance is reproduced by the sequencer, playing back the song data, using a tone generator capable of accurately producing various instrument sounds - including that of a piano. Looked at in another way, the relation of the sequencer and the tone generator is similar to that of the pianist and the piano - one plays the other. Since digital instruments handle playback data and the actual sounds independently, we can hear our piano performance played by another instrument, such as guitar or violin. ■ Example Keyboard Data Voice number (with what voice) 01 (grand piano) Note number (with which key) 60 (C3) Note on (when was it pressed) and note off (when was it released) Timing expressed numerically (quarter note) Velocity (about how strong) 120 (strong) Panel operations on the PSR-2100/1100, such as playing the keyboard and selecting voices, are processed and stored as MIDI data. The auto accompaniment styles and songs also consist of MIDI data. MIDI is an acronym that stands for Musical Instrument Digital Interface, which allows electronic musical instruments to communicate with each other, by sending and receiving compatible Note, Control Change, Program Change and various other types of MIDI data, or messages. The PSR-2100/1100 can control a MIDI device by transmitting note related data and various types of controller data.The PSR-2100/1100 can be controlled by incoming MIDI messages which automatically determine the tone generator mode, select MIDI channels, voices and effects, change parameter values and of course play the voices specified for the various parts. MIDI data has the following advantages over audio data: • The amount of data is much less, letting you easily store MIDI songs to floppy disk. • The data can be effectively and easily edited, even to the point of changing voices and transforming the data. Even though it is a single musical instrument, the PSR-2100/1100 can be thought of as containing several electronic components: a controller, a tone generator, and a sequencer. MIDI messages can be divided into two groups: Channel messages and System messages. Finally, we'll take a look at the actual data that gets recorded and that serves as the basis for playing the sounds. For example, let's say you play a "C" quarter note using the grand piano sound on the PSR-2100/1100 keyboard. Unlike an acoustic instrument that puts out a resonated note, the electronic instrument puts out information from the keyboard such as "with what voice," "with which key," "about how strong," "when was it pressed" and "when was it released." Then each piece of information is changed into a number value and sent to the tone generator. Using these numbers as a basis, the tone generator plays the stored sampled note. ■ Channel Messages The PSR-2100/1100 is an electronic instrument that can handle 16 channels (or 32 channels, when using the USB terminal). This is usually expressed as "it can play 16 instruments at the same time." Channel messages transmit information such as Note ON/OFF, Program Change, for each of the 16 channels. Message Name Note ON/OFF Program Change Control Change PSR-2100/1100 Operation/Panel Setting Messages which are generated when the keyboard is played. Each message includes a specific note number which corresponds to the key which is pressed, plus a velocity value based on how hard the key is played. Voice selecting (control change bank select MSB/LSB setting) Volume, panpot (Mixing Console), etc. The performance data of all songs and styles is handled as MIDI data. PSR-2100/1100 159