They have a speaker with the same (or similar) ribbon midrange and tweeter as the FR30. I don't know any details beyond that. It looks like its just used for level monitoring at that point. The final mixing seems to be done on the FR30s themselves. This is in contradiction to them appearing to use ATCs, but its hard to say more beyond that. One thing that is distinctive, though, is that if you listen to the samples in the Octave catalog, the mixing suddenly changes in tonality and character. It becomes rather dull and uninteresting, which is in contradiction to Paul's sentiments on things being intimate and revealing. I don't have any conclusion for that, other than being confused. One could argue skullduggery given that the video footage of the FR30s in action has the common theme of having Octave music as the source material, but in the video we have a clear audio reference with them doing the warm-up session in that the microphone seems to have a reasonable degree of fidelity. However, there is a distinct change when we hear it on the monitors. Granted, given all we know about speaker directivity and radiation patterns along with the use of planar ribbon drivers, drawing conclusions from that is beyond problematic, and these seem to just be used for monitoring of the levels. But I cant help but notice that they have the same sort of tonal character as the finished mixes. On top of this, Paul naturally is furiously scrubbing the comments in that video. My cousin is a mixing and mastering engineer who has worked at several prominent record labels, it would be interesting to get his take if I manage to see him at some point. But to me its just a head scratcher. Nothing seems to pass the smell test, but this was the theme with their electronics as well.