First diagram: Yes, the signal flow works but since the H90 lives post-preamp I feel the splitter and parallel mixer are both unnecessary. If you send a mono signal to the H90 on Insert mode set to parallel routing, the H90 will internally split that signal to each effect and output from each algorithm in stereo anyway. Plus, you’d have the added benefit of using the H90’s stereo fx loop to add an external effect without committing to it living on either path of the hardware mixer.
Second diagram: This gets closer to what I was talking about in the first diagram. I do not understand the benefit of the splitter here. If you go straight into Input 1 of the H90 from the output of your preamp (after the Sentry) in mono, the H90 takes care of splitting that signal internally. It’s not necessary to use the Insert in the manner you’ve laid out if what you want to do is run effects in parallel. The H90 does it automatically.
