Solo (PFL and Solo in Place)

The PFL solo switch allows you to monitor an input
signal independently of any other instruments that have
been connected, which is useful for troubleshooting, or
setting an instrument’s Input Preamp Gain and EQ
setting.
Pre-Fade Listen (PFL) is a type of solo that allows you
to monitor your sound BEFORE THE FADER. In other
words when you move the input fader in PFL mode the
level will not change, nor will you hear any effects.
Because effects and volume are not a distraction, PFL solo
is very useful for setting proper input preamp levels.
Some Soundcraft mixers use SOLO IN PLACE, which
allows you to monitor signals after the fader in their true
stereo image, and with any effects that have been added.
This type of Solo is less good for level setting, but more
useful in mixdown situations for auditioning sounds.