Usb Audio Device Mode - Vox -01 Operating Manual

USB audio device mode

When starting this module, a special mode of the device is activated, in which it performs
no other tasks than simply streaming audio to a PC, applying the VOX-01 level
calibration. This is done in the form of a single-channel stream, at a fixed bandwidth of
48 kHz and a bit depth of 32 bits. All current versions of MS Windows should
recognize the VOX-01 while operating in this mode as a "USB audio device" and may
also indicate that it is an "omnidirectional microphone." Once the device is detected by
Windows, make sure that the software that you intend to use is also configured for the
device. A small Windows test application is included on the USB flash drive that came
bundled with your VOX-01
The VOX-01 display while in USB audio mode
Once the device is connected via USB (and the PC has recognized it as an audio device), an
indication showing "USB connected" will appear. Once data starts streaming, an animated
picture and the message "data link active" will indicate that data is being transferred. This
will happen once an application initiates streaming audio from the VOX-01.
The audio signal is scaled so that full scale corresponds to 150 dB (e.g, a signal with a level
of 94 dB will correspond to a level of -56dB relative to full scale). Windows drivers and ap-
plications may digitally adjust the level, by applying software-based volume settings. If left
unadjusted, the volume of the signal when directly played back on the PC may be quite low.
This is done on purpose, so that high levels of up to 150 dB can be accommodated. Given
the fact that 32-bit audio has a dynamic range of 192 dB, this does not affect the integrity of
even the lowest-level signals. The entire dynamic range of the VOX-01 is available
digitally. If the audio is too soft, simply adjust the volume control on the PC.
If you want to explicitly calibrate your windows software to work with the VOX-01, press
the "cal" button to generate a synthetic 1000Hz sine at 94.0 dB. If you calibrate your
software to this level, then all audio measured by the VOX-01 will be registered at the
correct levels in your software as well. Press "mic" to return to normal operation.
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VOX-01 Operating Manual