Digital filters are used to remove artifacts in the digital signal caused by audio sampling. The Geek Out offers the following filters:
TCM (Time Coherence Mode) – Uses LH Labs minimum phase digital filter and time optimization algorithm which removes all pre-ring from the original signal, and realigns the impulse response. This presents the listener with a more well-defined and natural soundstage.
FRM (Frequency Response Mode) – Uses LH Labs slow roll-off linear digital filter and frequency domain optimization algorithm to provide a smoother and clearer sound with even lower THD+N.
The top button (closest to the computer) is the TCM filter, with the bottom button being the FRM filter.
The top 2 LEDs (out of the 3 on top) will light up when TCM is engaged, and the bottom 3 LEDs (out of the 4 on the bottom) will light up when FRM is engaged.
Please note, after a few seconds the LEDs will revert to show the audio format/sample rate of the current/previous audio file playing.