Yamaha CLP-155 Owner's Manual - Page 18

MIDI Functions q A Brief Introduction to MIDI MIDI OUT Clavinova MIDI Cable MIDI IN DOU-10 MIDI OUT Data Being Recorded Playback Data MIDI IN MIDI OUT MIDI IN DOU-10 Clavinova MIDI, the Musical Instrument Digital Interface, is a world-standard communication interface that allows MIDI-compatible musical instruments and equipment to share musical information and control one another. This makes it possible to create "systems" of MIDI instruments and equipment that offer far greater versatility and control than is available with isolated instruments. For example, most MIDI keyboards (including the Clavinova, of course) transmit note and velocity (touch response) information via the MIDI OUT connector whenever a note is played on the keyboard. If the MIDI OUT connector is connected to the MIDI IN connector of a second keyboard (synthesizer, etc.) or a tone generator (essentially a synthesizer with no keyboard), the second keyboard or tone generator will respond precisely to notes played on the original transmitting keyboard. The result is that you can effectively play two instruments at once, providing thick multiinstrument sounds. This same type of musical information transfer is used for MIDI sequence recording. A sequence recorder can be used to "record" MIDI data received from a Clavinova, for example. When the recorded data is played back, the Clavinova automatically "plays" the recorded performance in precise detail. The examples given above really only scratch the surface. MIDI can do much, much more. The CLP-154S/155 offers a number of MIDI functions that allows it to be used in fairly sophisticated MIDI systems. NOTE • Always use a high-quality MIDI cable to connect MIDI OUT to MIDI IN terminals. Never use MIDI cables longer than about 15 feet, since cables longer than this can pick up noise which can cause data errors. q MIDI "Messages" Transmitted & Received by the Clavinova The MIDI information (messages) transmitted and received by the Clavinova are as follows: Note and Velocity Data This information tells the receiving keyboard or tone generator to play a certain note (specified by the MIDI note number) at a certain dynamic level (specified by the MIDI velocity value). Note and velocity data is transmitted by the Clavinova whenever a key is pressed, and the Clavinova's internal AWM tone generator will "play" the corresponding note(s) whenever note and velocity data is received from an external MIDI device. Program Change Numbers The CLP-154S transmits a MIDI program change number between 0 and 5, and the CLP-155 transmits a MIDI program change number between 0 and 7 when one of its voice selectors is pressed. This normally causes the correspondingly numbered voice to be selected on a receiving MIDI device. The Clavinova will respond in the same way, automatically selecting the appropriate voice when a MIDI program change number is received. See "Program Change ON/OFF" on page 17 for information on turning program change number reception and transmission ON or OFF. Control Change Numbers Control Change data representing Damper pedal operation is transmitted by the Clavinova whenever one of these pedals is used. If the receiving device is a tone generator or another keyboard, it will respond in the same way as the Clavinova's internal tone generator when one of the pedals is used. The Clavinova also receives and responds to the appropriate control change data. See "Control Change ON/OFF" on page 18 for information on turning control change number reception and transmission ON or OFF. 15