User manual ART DIO

[. . . ] The ART DI/O TABLE OF CONTENTS Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AC Power Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Audio Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] When set to one of the internally generated sample rates (44. 1, 48, 88. 2, or 96kHz), the DI/O provides the Master clock source from its internal crystal clock. When set to the External Sync position, the DI/O will use the S/PDIF In jack as the source of its Master clock. The green (Ext. ) LED indicator will light solid as long as the source has valid audio sync. It will flash if the data on the S/PDIF input jack does not contain valid audio data. When this occurs the D/A will mute its audio outputs to prevent unwanted noise. The A/D will still digitize audio and track the external Master clock. SIGNAL LEVEL LED INDICATORS The three Signal Level LED Indicators are designed to help set levels before the A/D, to maximize your dynamic range. The green (-20dB) LED comes on when the signal at the A/D is 20dB below full-scale digital clipping on signal peaks. It just starts to come on when the average signal is around 30dB below clipping. You should increase your input signal level, or the DI/O's Input Gain until this light is on solid whenever there is signal for best performance. The red (0dB) LED comes on when the signal at the A/D is 3dB away from full-scale clipping. With most audio material, you would increase the input signal or Input Gain until this light just starts to come on during signal peaks. The yellow (Warm) LED comes on whenever the tube is adding warmth or character to the signal. This is a function of both the input signal level and the Tube Warmth control. -5- TUBE WARMTH CONTROL This control allows you to vary the tube circuits warmth contribution to the audio signal chain. At the Clean end, there is essentially no tube processing and the yellow Warm LED should not light. As you turn up the control, the drive to the tube is increased while its output is adjusted, to maintain a fairly constant output signal to the A/D. At higher signal levels you will see the yellow (Warm) LED start to come on, indicating that the tube circuit is doing some of the processing. At the full Warm position, you will see the Warm LED on more of the time, even at lower signal levels. Audibly, at this setting, the tube adds low-order harmonics that tend to musically "thicken" the signal. Both of these effects are what give the DI/O that "Analog Tape Saturation" sound at higher levels with higher settings of the Warmth control. POWER LED INDICATOR The green Power LED lights solid to indicate that the DI/O is receiving adequate power from its external power source. If it ever flickers, check the connections, power adapter, or line voltage. -6- CONNECTIONS variety of equipment. [. . . ] Be sure to have monitoring levels turned DOWN before "testing" the sound. In the event that you need to replace them, A R T suggests that you do so with tubes available from A R T. These are matched to the DI/O and will yield consistent sonic results. You can replace the tubes with other brands, however A R T has no responsibility for the resulting sound quality. - 12 - They may sound better, they may sound worse. [. . . ]