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Message: [QUOTE="Bombastus, post: 91735, member: 2178"] MIDI Clock sends 24 timing pulses per quarter note, giving connected gear a tempo reference that can rise or fall with the master. MIDI Time Code does something else entirely. It tells compatible equipment where playback sits on an hours, minutes, seconds, and frames timeline. The difference matters as soon as you synchronize hardware with a DAW. A drum machine usually cares about beats, tempo changes, and where a pattern should start, while a video rig or second workstation may need an exact time position. Calling both jobs “MIDI sync” hides the part you actually need to configure. Start, Stop, Continue, Song Position Pointer, Clock, MTC, and MIDI Machine Control also get lumped together in setup menus. They cooperate, but they are not interchangeable. A grasp of [B][URL='https://goldmidi.com/community/resources/what-is-midi.658/']MIDI timing message structure[/URL][/B] makes stubborn sync problems much easier to isolate. [HEADING=2]MIDI Clock follows musical tempo[/HEADING] MIDI Clock is built around musical time rather than clock-on-the-wall time. The master sends 24 Clock messages for every quarter note, so increasing the master tempo makes those pulses arrive faster. A receiving drum machine, sequencer, delay, or arpeggiator can use the stream to keep its tempo-dependent behavior aligned. Clock alone does not tell a device which bar or beat the song is currently on. Start tells compatible equipment to begin from its starting position, while Continue tells it to resume from its current position and Stop halts playback. Those transport-style real-time messages give Clock useful context without turning Clock itself into a location system. Song Position Pointer fills part of the location gap. It carries a 14-bit count measured in MIDI beats, with each MIDI beat equal to six Clock pulses, which works out to a sixteenth-note position under the standard 24-pulse clock. A compatible sequencer can therefore jump to a musical position instead of always beginning from bar one. Support is the snag. Some devices follow incoming Clock perfectly but ignore Song Position Pointer, while others behave differently depending on whether the sender is configured for song-style or pattern-style sync. If a groovebox stays in tempo but starts its loop from the wrong place after you jump around a DAW timeline, the problem may be position support rather than bad clock timing. [HEADING=2]MTC follows an absolute timeline[/HEADING] MIDI Time Code is for positional synchronization measured in timecode rather than bars and beats. It carries frame-based location information derived from SMPTE-style timecode, including hours, minutes, seconds, frames, and the applicable frame-rate code. Tempo is not part of the message, so changing BPM is a separate job. During running playback, MTC commonly travels as Quarter Frame messages. Eight successive Quarter Frame messages are needed to convey a complete timecode value, and the sequence spans two frames. Full Frame messages serve a different purpose, allowing equipment to receive a complete location value when locating or while timecode is not running. This makes MTC useful when two systems must agree on where they are even if musical tempo is irrelevant. Picture playback, a second DAW, automation systems, and recorders can all care about 01 hours 12 minutes 08 seconds without needing to know whether the music underneath is 90 or 140 BPM. The separation is visible in [B][URL='https://patents.google.com/patent/WO2011133398A2/en']timecode synchronization system design[/URL][/B], where MIDI Beat Clock and MIDI Time Code are treated as distinct timing mechanisms with different information. In practical studio terms, MTC can keep two timelines located together while each system still needs the correct project tempo for bar-and-beat displays or tempo-driven processing. [HEADING=2]MMC handles transport without becoming the clock[/HEADING] MIDI Machine Control handles commands rather than continuous synchronization. It was designed for controlling machine functions such as play, stop, record, locate, and related transport operations on compatible equipment. Sending MMC therefore does not automatically make two devices share tempo or remain locked to the same time position. A common professional arrangement uses more than one mechanism at once. One device can send MMC commands to control another machine’s transport while MTC supplies the positional reference. Musical equipment elsewhere in the same setup can still receive MIDI Clock if arpeggiators, sequencers, or tempo-synced effects need to follow BPM. This split explains a lot of apparently broken setups. A remote transport button can successfully start a recorder even though its timeline drifts because transport control and synchronization are separate jobs. Likewise, an external sequencer can follow tempo while ignoring DAW timeline jumps because Clock arrived but useful position information did not. In a mixed hardware rig, those mechanisms can run side by side without duplicating one another. A DAW might send Clock to a drum machine, MTC to a recorder, and MMC transport commands to the same recorder, while Song Position Pointer helps a compatible sequencer recover its musical location after a timeline jump. One MIDI cable can therefore carry several kinds of sync information whose jobs remain deliberately separate. [/QUOTE]

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