19.2 Settings dialog - DDS

Usually soundcards and audio interfaces generate their internal clock (master mode) by a quartz. Therefore the internal clock can be set to 44.1 kHz or 48 kHz, but not to a value in be- tween. SteadyClock, RME's sensational Low Jitter Clock System, is based on a Direct Digital Synthesizer (DDS). This superior circuitry can generate nearly any frequency with highest pre- cision.

DDS has been implemented into the HDSP MADI with regard to the needs of professional video applications, as well as to maximum flexibility. The dialog DDS includes both a list of typical video frequencies (so called pull up/pull down at 0.1% and 4%) and two faders, which allow to freely change the basic sample rate in steps of 1 Hz (!).

The DDS dialog requires the HDSP MADI to be in clock mode Master! The frequency set- ting will only be applied to this one specific card!

Changing the sample rate in bigger steps during record/playback often results in a loss of audio, or brings up warning messages of the audio software. Therefore the desired sample rate should be set at least coarsely before starting the software.

DDS

Activates all settings of this dialog.

Value

Shows the sample rate as adjusted in this dialog. The sample rate is defined by the basic setting (Frequency), the multiplier, and the position of the activated fader.

Frequency

Sets a fixed basic sample rate, which can be modified by multiplier and fader.

Freq. Multiplier

Changes the basic sample rate into Single, Double oder Quad Speed mode.

Coarse

Fader for coarse modification of the basic sample rate. Click Active to activate it. Minimum step size 1 Hz.

Fine

Fader for fine modification of the basic sample rate. Click Active to activate it. Minimum step size 1 Hz.

Notes on the faders

A mouse click within the fader area, above or below the fader know, will move the fader with the smallest step size up or down. Holding the Ctrl key while clicking will cause the fader to jump to its center (0).

User's Guide HDSP MADI © RME

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Alesis Hammerfall DSP System manual Settings dialog DDS