Synchronization overview

Sonar supports several different types of synchronization, which rely on a variety of different clock sources:

 

Clock source	Timing is determined by
Internal	The clock on the computer motherboard
Audio	The clock on the computer’s sound card
MIDI Sync	The clock on an external MIDI device
SMPTE/MIDI Time Code (MTC)	A time code signal (in SMPTE or some other format) recorded on some external medium or generated and sent by Sonar

When you use either the internal or audio clock, Sonar can control other MIDI devices using MIDI Sync. In this case, Sonar is the “master” device and the other MIDI devices are the “slaves.”

When MIDI Sync is the clock source, Sonar operates either in response to incoming MIDI messages or as the sender. In this case, Sonar can be either the master or the slave. Note that audio playback is not supported when using MIDI Sync with Sonar as the slave.

When SMPTE/MIDI Time Code (SMPTE/MTC) is the source of timing information, Sonar operates in response to incoming MTC messages. These messages could be generated by:

An external MIDI device that is capable of generating MIDI Time Code (like the Roland VS880)

A MIDI interface that is converting other time code signals (like SMPTE, EBU, or film time code) into MIDI Time Code

When you use some of these synchronization options, some Sonar commands work differently. This section describes each of the synchronization options, how and why each is useful, and the effect each option has on other features and commands.

The Sync module in the Control Bar lets you change back and forth quickly between the different clock settings.

Figure 532. The Sync module.

A. SMPTE/MTC format B. Incoming timecode C. Sync type D. Transmit MIDI Sync E. Transmit MTC Sync

The Sync module contains the following controls:

SMPTE/MTC format. Select the time code format. The following frame rates are supported:

23.976 frames per second (FPS). Typically used with H.264/MPEG-4 AVC video.

24 frames per second (FPS). Used for theatrical film worldwide. Any film in North America or Japan uses this setting.

25 FPS. Used for PAL/SECAM video and some film in countries that use 50 Hz wall electricity. This is the setting to use when synchronizing to any European video format.

29.97 FPS Drop. NTSC broadcast and long format video in North America and Japan. This setting synchronizes the video perfectly with Sonar, but the sequencer position displayed in the Now Time and Big Time displays will gradually drift and become incorrect over long periods of time. The audio and MIDI synchronization to the external device will not be affected by this discrepancy.

29.97 FPS Non Drop. NTSC non-broadcast and short length video in North America and Japan. Used for some music projects. This setting synchronizes the video perfectly with Sonar, but the sequencer position displayed in the Now Time and Big Time displays will gradually drift and become incorrect over long periods of time. The audio and MIDI synchronization to the external device will not be affected by this discrepancy.

30 FPS Drop. Not a standard type of timecode, used rarely for speed correction and transfer problems in tape based systems.

30 FPS Non Drop. Most music projects and some film in North America. This is the best choice for any music project and should be used unless the situation dictates otherwise.

Incoming timecode. Shows the current time of incoming time code when synchronizing to an external device.

Sync type. Select the sync type; right-click to show synchronization settings. The following sync types are supported:

Internal Sync . Timing is determined by the clock on the computer motherboard.

MIDI Sync . Timing is determined by the clock on an external MIDI device.

SMPTE/MTC Sync . Timing is determined by a time code signal (in SMPTE or some other format) recorded on some external medium or generated and sent by Sonar.

Audio Sync . Timing is determined by the clock on the computer’s audio interface.

Transmit MIDI Sync . Transmit MIDI Sync to external MIDI devices, such as drum machines, stand-alone MIDI hardware sequencers, and sequencers built into MIDI keyboards (only available when using the Internal or Audio clock). Sonar sends messages to all other devices to start and stop playback and to keep all the devices in sync. Sonar can send MIDI Sync on multiple MIDI output ports. For details, see MIDI synchronization.

Transmit MTC Sync . Transmit MIDI Time Code (MTC) to external devices that can receive MTC. SMPTE/MTC is a position and timing reference that indicates the current location in the project and how quickly the project should be playing. SMPTE/MTC time code labels the position in a project in hours, minutes, seconds, and frames. The speed of playback is indicated by a frame rate. Sonar can send MTC on multiple output ports simultaneously. For details, see SMPTE/MIDI time code synchronization.

You can also choose the sync mode as follows:

1.	Go to Edit > Preferences > Project - Clock.

2.	Under Source, select the desired clock source.

3.

Click OK.

The clock source and the type of synchronization that is used are options that are stored as part of your project files. For example, one of your projects might be set up to use the internal clock; a second might use the Audio clock and MIDI Sync with Sonar as the master timing source; and another might use SMPTE/MTC Sync as the clock source.

Many technical support requests concern synchronization problems, which are among the hardest to diagnose. If you experience problems, before you contact support, perform as much experimentation and gather as much information as possible about what does and doesn’t work. The more prepared you are, the more we can help.