User`s guide

Windows Driver 4.x © RME
39
9.5 Recording a Submix - Loopback
This chapter is not valid for the HDSP MADI, please refer to the original manual (no internal
loopback available).
HDSP and HDSPe systems include an internal loopback function, from the Hardware Outputs to
the recording software. Instead of the signal at the hardware input, the signal at the hardware
output is sent to the record software. This way, complete submixes can be recorded without an
external loopback cable. Also the playback from a software can be recorded by another
software.
The function is activated by the Loopback button in the Settings panel of the Hardware
Outputs. In loopback mode, the signal at the hardware input of the corresponding channel is no
longer sent to the recording software, but still passed through to TotalMix. Therefore TotalMix
can be used to route this input signal to any hardware output. Using the subgroup recording, the
input can still be recorded on a different channel.
As each of the stereo hardware outputs can be routed to the record software, and none of these
hardware inputs get lost, TotalMix offers an overall flexibility and performance not rivalled by
any other solution.
The risk of feedbacks, a basic problem of loopback methods, is low, because the feedback can
not happen within the mixer, only when the audio software is switched into monitoring mode.
The block diagram shows how the software's input signal is played back, and fed back from the
hardware output to the software input.