Owner`s manual

15
If the INT203 powers up with the computer connected and with no external
power supply connected, then obviously bus power is available. If preferred, the
external power supply may still be connected in that case. The INT203 then
automatically switches over to the external power supply.
Figure 2.1: 4 pin Firewire socket
2.1.6 Stand-Alone Operation as a Digital Level Control
Device
If the INT203 is not connected to a computer (no Firewire connection), the
INT203 enters the stand-alone level control mode. In this mode the input selected
with the input selector switch (RCA or XLR connector) is fed to both outputs
(RCA and XLR) via the level control algorithm. With the (optional) IR remote
control unit, the level of the digital signal can be changed. The INT203 firmware
features as described below are still supported in the level control mode. Namely
the bit transparency check and the absolute polarity reversal switch. Note, if
the INT203 is not connected via Firewire, an external power supply needs to be
connected to the INT203.
2.1.7 Firmware features
The firmware in the INT203 allows for level control and for absolute polarity
reversal of the digital audio output. These features are only accessible via the
(optional) Remote Control unit (section 2.3.5). If the remote control unit is not
used, the gain stays at 0 dB as set in the factory settings. 0 dB means a fully bit
transparent transfer. The absolute polarity is set to 0
◦
, i.e. the polarity is not
changed. The level control is properly dithered, i.e. there are no artifacts due to
the level control. Refer to previous sections for more background information on
dithering (1.4) and digital level control (1.5).
In addition the firmware allows for testing bit transparency of the music
player program running on the computer. This is useful to find out the proper
settings/configuration of the player program to achieve bit transparency at the