Understanding dLive USB Recording and Playback
Posted by Ben Morgan, Last modified by Ben Morgan on 15 February 2018 10:06 AM

dLive offers the ability to record and playback stereo (2-track) audio directly on to a USB device.

Supported sample rates for playback are 44.1kHz, 48kHz and 96kHz.

The recording format is .WAV 96kHz 24-bit.

dLive audio recording requires the USB storage device to support high sustained transfer rates. Not all USB devices will guarantee flawless performance - when a USB device causes a pause that is longer than the buffer time in the mixer, a dropout occurs and data is lost.

Please refer to the following guidelines for sourcing a suitable USB device:

  • USB flash 'key', 'stick', or 'thumb drive' - Suitable keys are listed further down in this article, but be aware of possible batch variance in memory chipsets and performance.
  • SSD drives - generally suitable for recording but can be prone to performance degradation over time, also some forms of wear levelling and 'garbage collection' algorithms can cause write speeds to become reduced during recording. Tested SSD drives are listed further down in this article, but be aware of possible batch variance in memory chipsets and performance.
  • HDD drives - magnetic drives are generally suitable for recording but can suffer from physical disturbances such as vibration due to low frequency exposure, which can throw the head off-track and cause a delay while the actuator repositions it, eventually impacting on the input/output performance.
  • SCSI drives - hard drives using the SCSI command protocol ATAPI are not supported. Only drives that communicate over USB Attached SCSI are supported. This is not obvious when looking at drives and you will need to consult the manufacturer’s data

The smallest USB drive size that should be used with dLive is 2GB.

Maximum USB drive size (FAT32 file system limit) is 2TB.

We recommend you use the USB hard drive for dLive USB Recording and Playback only. Do not use it for other applications including storing shows or installing firmware.

Format the hard drive on the dLive mixer before use. This clears the drive, sets up the dLive recording and playback directory structure, and formats into FAT32 with a constant cluster size of 32kB.


Additional notes

Please refer to the dLive Firmware Reference Guide for an overview of dLive supported file formats, data rate, folder structure and file naming, patching and instructions on playback and recording.

The maximum file size on FAT32 is 4 GB. dLive audio data rate per track is 33.8MB per minute / 2025MB per hour. This allows a maximum recording time of 118 minutes.

Note - .wav files imported to the USB drive for Stereo playback via dLive must be INTERLEAVED stereo tracks, and placed into the AHDLIVE/USBPLAY folder.

Note - a USB drive that works well in the DATA socket (i.e. for storing shows and installing firmware) will not necessarily have the performance requirements for USB Playback and Recording


DO’s and DON’TS

Recommended best practices for recording with dLive:

  • Format the USB device via the mixer
  • Arm recording before needing the recording to start
  • Press play to start recording, and leave the drive continuously recording for the total time of the recording (try not to stop start the recording)
  • Press stop once you have finished, and wait for the drive to process the audio
  • Remove the drive and back up the recorded material onto your computer