Correct, we supply two sets of audio output jacks because many users like this as it makes connection to a separate subwoofer amplifier easy.
You could also drive a second power amp to run speakers in some remote location.
Note that both sets of audio outputs provide identical signals, driven by the normal audio output circuits.
If the preamplifier has our phase inverter bridge circuits option, then the Line Out 2 jacks will provide audio signals 180 degrees out of phase with the Line Out 1 jacks. This is used to allow bridged mode operation of many stereo amplifiers.
Regards,
Frank Van Alstine