Probably it's a well known thing but i want to share it anyway. The line out of the Pathfinder is known to be not bad at all to go direct into P.A. but it can get better if you use a preamp pedal, in my case a Joyo American sound. Especially if some drives are used it can sounds a bit fizzy into P.A. but with this preamp it's a lot smoother to me, i guess something with a speaker sim. is needed. I've tried the preamp as last pedal in chain into the amp's input and from the line out of the Vox straight to mixer or another way is connecting the line out of the amp into the input of the preamp, and the output of the pream into the P.A. In the first case the preamp will affect the sound that is coming from the speaker because is in your pedal chain. In the second case the preamp will not affect the sound that is coming from the speaker because is direct from the line out. In both cases the sound coming from the P.A. it's much better to me. I also tried with a hughes and kettner red box 3 but i prefer the preamp because of the very good eq. Cheers.