I have a Pod X3 Pro that I run through a QSC power amp into a 2x12 cab. I'm going from the 1/4 INCH (Live) OUTPUTS on the back of the X3 Pro into the QSC, and I have the AMP/LINE selector switch set to AMP. I usually have both the QSC and the X3 Pro turned up pretty high to get a decent volume. Yesterday I tried switching to LINE and the signal got much louder, to where I always thought it should be. I always thought the AMP setting should be selected if you're sending the signal to an amplifier - makes sense, right? But I'm thinking now that AMP means if you're sending it into the instrument input on the front of a typical guitar amplifier, and that LINE should be used if sending the signal to a power amp. The names are a bit misleading (at least to me) and the manual doesn't go into any further detail.
Is this correct? Should I be set to LINE when sending into an external power amp?