Loop-back settings

gives the delay of the sound card in samples. The delay is found by doing a MLS measurement of the sound card with its input connected to the output using a cable. Plotting the first part of the resulting impulse response using Time Data as plot-type and Samples as x-axis, will show the delay. In addition to being used for the loop-back, this setting is also used for the Yes, my sound card ‘is synched’ mode.

gives the input line used when performing a loop-back measurement. For the Digigram® cards, Analog Input should be selected, but for other sound cards it is usually Mic or Line.

gives the channel that the loop-back is to be connected to. If the loop-back input is stereo, it is usually connected to Right channel. But if it is mono (e.g. the Mic input), it must be set to Left.

should be checked if problems occur when measuring in loop-back mode. A short MLS signal is used for the synchronization instead of the standard pulse. This signal is less prone to noise, but may demands a fast PC since will need more processing. If you are using a sound card capable of measuring DC offset (e.g. TB Tahiti/Monterey) it is strongly recommended to use this setting.