Simply select the channel you wish to Solo/PFL and select SIP or PFL in the SOLO CONTROL menu on the lower right side of the console. You may choose between PFL (Pre Fade Listen)/ AFL (After Fade Listen,) and SIP (Solo-In-Place). There is a Clear Solo function which will clear the solo function from all 16 channels. You also have a trim adjust for the Solo system, this is the final fader on the masters bank.