you have two basic options, at least, both of them relying on a separate audio output bus where you do insert all the fx plugins that you want (reverb, compressors, etc.) and that, of course, you should add or include on the export mix-down selection anyway:
1. have all the 3 guitar tracks assigned to that output to that bus; all fx in that target bus will apply to all tracks outputs as if it were the default master as usual (but it doesn't get any of the 3 guitars sound whatsoever);
2. have an aux-send inserted on each track and directed to that output bus; the alternate bus will become the wet sinal while the former (master) will go as the dry one;
hi,
you have two basic options, at least, both of them relying on a separate audio output bus where you do insert all the fx plugins that you want (reverb, compressors, etc.) and that, of course, you should add or include on the export mix-down selection anyway:
1. have all the 3 guitar tracks assigned to that output to that bus; all fx in that target bus will apply to all tracks outputs as if it were the default master as usual (but it doesn't get any of the 3 guitars sound whatsoever);
2. have an aux-send inserted on each track and directed to that output bus; the alternate bus will become the wet sinal while the former (master) will go as the dry one;
hth.
cheers