Synchronization; File Management; File Type; File Structure - Sound Devices 664 User Manual And Technical Information

664 User Guide and Technical Information
two frame rate options in 47.952kF mode. The time code frame rate can be set to 23.97 while the fi le
is identifi ed as 24ND or it can be set to 29.97ND while the fi le is identifi ed as 30ND. By default, when
47.952kF mode is selected the frame rate is changed to 29.97ND and identifi ed as 30ND unless the
Frame Rate was already set to 23.97 in which case it will remain at 23.97.

Synchronization

A stable sample clock source is essential for high quality digital audio. Setups involving multiple digi-
tal recording/playback devices often require that all devices are locked to a common clock reference to
ensure they are synchronous, i.e. run at the same speed and in phase with one another. The 664 uses
rock-stable word clock and PLL circuitry to generate its internal clock frequency.
The 664 can act as either a clock master (Setup Menu option TIMECODE/SYNC > Sync Reference
set to Internal), where it is the provider of word clock, or as clock slave (Setup Menu option
TIMECODE/SYNC > Sync Reference set to Word Clock), where it locks its internal word clock to a
received external master reference clock. External word clock signal is provided via the Word Clock
input BNC on the Rear Panel.
When accepting digital input signal, the 664 always converts the sample rate to the recorder's sample
rate. During playback, the 664 only uses its own word clock, ignoring external word clock.

File Management

The 664 writes fi les to both CompactFlash (CF) and Secure Digital (SD) storage media. Storage media
must be formatt ed as FAT32 volumes prior to use with the 664. CF and SD storage media inserted
into the 664 can be formatt ed with Setup Menu option FILE STORAGE > Erase/Format CF and
FILE STORAGE > Erase/Format SD respectively. The FAT32 fi le system is compatible with all major
operating systems. To manage fi les on 664 media using a computer, simply remove the media from
the 664 and insert into a compliant CF or SD card reader connected to a computer.

File Type

The 664 records audio to the industry-standard Broadcast Wave fi le format. Additionally, the 664 can
record to MP3 format. Recording WAV or MP3 is selectable per media, from the Setup Menu items
RECORDER > Record to CF, and RECORDER > Record to SD. The 664 can write fi les to both cards
simultaneously.
WAV (Broadcast WAV)
The 664 writes AES-31 Broadcast Wave formatt ed fi les. The audio fi les created by the 664 include ad-
ditional information (Metadata) in the fi le's header, BEXT (Broadcast Audio Extension) and iXML data
chunks. See Metadata section of Specifi
cast wave data chunks will simply ignore them.
Wave Agent Beta allows for the splitt ing (de-interleaving) of polyphonic fi les into separate fi les for each track.
MP3
MPEG-1 Layer III is a lossy compression algorithm, often used for music and transcription recording
purposes. The 664 records two-channel MP3 audio fi les with data rates of 320 kb/s, 192 kb/s, or 128
kb/s.

File Structure

The 664 records polyphonic audio fi les. A polyphonic audio fi le is one fi le with multiple tracks. When
recording polyphonic fi les, one fi le will be created per take. A polyphonic take and fi le name consists
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v. 1.0 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
cations. Software that does not recognize these additional broad-