Sound Devices 744T - Manual (Page 61)

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After recording to an external drive has stopped, it may take several seconds for the 744T to finish
“housekeeping” 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 744T provides power for bus-powered FireWire drives. The follow-
ing conditions should be observed when connecting to bus-powered drives.
• Bus powering a drive requires external DC powering of the 744T. The 744T 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 744T.
• 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 744T. 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 744T attach a FireWire
drive and run the media speed test selected from the Setup 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. Firmware revisions later than 2.00 support
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 at or 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.