The diagram below is a simplified representation of the signal flow through the miniDSP Flex (with Dirac Live):
The audio signal flows from left to right in the above diagram:
One of the five stereo input sources is selected by the user.
The selected stereo signal is passed through the input channel processing blocks: level metering and Dirac Live.
The processed input channels are fed into a 2-in 4-out routing matrix that routes/mixes the two processed input channels to the four output channels.
Each output channel runs a comprehensive set of DSP functions: parametric EQ, crossovers, level metering, delay, output gain and compressor.
The combination of the routing matrix and the crossover blocks on the output channels is what gives the miniDSP Flex (DL) the ability to be used in many different system configurations.
When using Dirac Live, it is important to first set up the routing matrix and the output channel crossovers using the miniDSP Device Console. Then in the Dirac Live app, export the generated filters into the same-numbered slot. For example, if you set up preset 2 in DC, export the filter in Dirac Live to slot 2.