Components

• Separate input-gain adjustment
• Input-phase inversion
• Output-signal re-quantization with noise shaping and dithering

Variable Output Formats

The XTF board provides for re-quantization of NEXUS 24-bit data to 16-bit or 20-bit formats for external applications. Inaccuracies emerging from truncation errors are minimized by re-quantizing using a dithering algorithm.
In addition, a selectively engaged noise-shaping function moves the noise energy up to frequency ranges less perceivable to the human ear. The noise reduction achieved in the range below 1 kHz is approximately 15 dB. Noise shaping is computed on the integrated signal processor on the basis of a 5th-order algorithm.

Sample-rate Converters

For handling asynchronous signals, sample-rate converters are optionally available for both the input and the output. If equipped with sample-rate converters, the board handles input signals with a sample rate of 32 to 50 kHz. In this case, the output sample rate can be set to either 44.1 kHz or 48 kHz. The board includes a quartz-controlled generator producing a 44.1-kHz or 48-kHz wordclock. Accuracy is better than 50 ppm.

Separate Synchronisation

The XTF also allows the output signal to be synchronised to the input signal independent of the system clock. Thanks to the sample-rate converters, the audio signal is still available on the NEXUS system.

Indicators

A front-panel LED indicates the status of the input signal.

Ports

The Tascam format uses 25-pole D-Sub ports. In addition, a BNC port is available for setting up the slave configuration of a connected unit. This port supplies a wordclock signal shifted by 90° (Tascam standard).