Yes, it's through the Blackstar. The amp is plenty loud enough but it's a case of clearly hearing what I'm doing within the context of the band, especially if I move around the stage. We did a gig a while back where we could use the house PA and it was fantastic. We all had our own monitor and I just asked the woman doing the sound to increase how much of myself I was hearing through my monitor until I was happy. Normally we don't have that luxury. Ideally, having a full set of individual wedge monitors would be great or IEM but we don't have the money for that so as the Quattro has dual mono outputs, I wondered if I could use that to help me hear myself in the mix a bit better without it affecting the sound out front.