1. System Real-Time Messages:
- MIDI 1.0 defined only one system real-time message, the "Song Position Pointer," used for indicating the current position in a MIDI sequence.
- MIDI 2.0 introduced additional system real-time messages, including Start, Stop, Continue, Clock, Clock Start, and Active Sensing, providing more control and synchronization capabilities.
2. MIDI Channel Pressure:
- MIDI 1.0 did not include MIDI Channel Pressure messages.
- MIDI 2.0 introduced MIDI Channel Pressure messages, allowing for the control of overall dynamics for a specific MIDI channel, adding expressiveness to performances.
3. MIDI Pitch Bend Range:
- MIDI 1.0 limited the pitch bend range to two semitones in either direction.
- MIDI 2.0 expanded the pitch bend range to ±8191 microtones (approximately -2 octaves to +2 octaves), providing finer control over pitch bending.
4. MIDI Polyphonic Key Pressure:
- MIDI 1.0 did not support polyphonic key pressure messages.
- MIDI 2.0 added MIDI Polyphonic Key Pressure messages, enabling the control of the pressure applied to individual notes of a polyphonic instrument, enhancing the level of expressiveness.
5. Universal Non-Realtime System Exclusive Message:
- MIDI 2.0 introduced the Universal Non-Realtime System Exclusive Message, allowing for the transfer of large amounts of data between MIDI devices for various purposes, such as extended control parameters or sample data transfer.
6. General MIDI Standard:
- MIDI 2.0 incorporated the General MIDI Standard, which defined a set of standardized instrument sounds and percussion mappings for MIDI playback, ensuring consistent sound reproduction across different devices.
7. MIDI Machine Control (MMC):
- MIDI 2.0 introduced MIDI Machine Control (MMC), a protocol for controlling tape recorders, CD players, and other external devices synchronized to MIDI.
Overall, MIDI 2.0 specifications significantly expanded the capabilities and functionality of MIDI, providing more control, expressiveness, and standardization for MIDI devices and applications. While MIDI 1.0 devices can still communicate with MIDI 2.0 devices, the latter's enhanced features require compliant MIDI devices to take full advantage of its improvements.