Sound Devices 722 - Manual (Page 51)

722 User Guide and Technical Information
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722 will prompt the user to format the drive. If the drive is already formatted as a FAT32 volume the
drive will be ready to be selected as a storage medium. The front panel drive LED will illuminate to
show which drives are available for recording. To reformat an attached drive, follow the same pro-
cedure as formatting the internal hard drive, substituting the external drive menu selection for the
internal hard drive.
After recording to an external drive has stopped, it may take several seconds for the 722 to finish “house-
keeping” on drive. This is especially true when recording to DVD-RAM disks, which generally have
slower throughput than hard drives. When preparing to disconnect a FireWire drive, always observe the
amber activity LED labeled EXT. If it is lit, wait until it is off before disconnecting the drive. If the drive
is disconnected while the LED is on, there is a high likelihood that the file being written will be unusable
and there is a possibility of FAT corruption on the drive.
FireWire Bus Powering
The six-pin FireWire port on the 722 provides power for bus-powered FireWire drives. The following
conditions should be observed when connecting to bus-powered drives.
• Bus powering a drive requires external DC powering of the 722. The 722 cannot operate bus-
powered drives from an attached Li-ion battery.
• When recording in realtime to bus-powered FireWire drives the XL-1394 FireWire Power Filter
is recommended. This filter network isolates the electrical noise in bus-powered drives from
the 722.
• While hot-swapping FireWire cables is possible it is recommended to attach bus-powered
drives with the recorder turned off.
Qualified Drives
External FireWire storage volumes that can be formatted and addressed as FAT32 can be used with
the 722. These include:
• external hard drives, bus-powered or mains powered. Drives as large as 2 TB can be addressed,
• FireWire CompactFlash card readers,
• DVD-RAM drives.
FireWire drives use a variety of chipsets to perform conversion from the drive’s native format (i.e.
IDE) to FireWire. Sound Devices has tested and qualified enclosures and card readers which use the
Oxford 911, Oxford 922, PL3507, GL711, and FW912 chipsets. Other chipsets may operate, but Sound
Devices does not officially support them. To check for compatibility with the 722 attach a FireWire
drive and run the media speed test selected from the User Menu. This will write, then read a file to
the drive. If the drive can perform this test then it can be used to record audio.
DVD-RAM Drives
DVD-RAM drives are essentially optical hard drives. Revision 2.00 firmware supports recording to
and playing back from DVD-RAM drives when formatted as FAT32 volumes.
When recording to DVD-RAM drives in realtime it is important to note the following:
1. Keep sampling rates below 48048.
2. Record to polyphonic file formats.
3. Use DVD-RAM drive mechanisms and media that support 3X recording speeds.
Post-record copying from internal hard drive (or CF) to external drives is recommended with material
recorded at high sampling rates.