I’ll bet sax sounds great through an H90. I don’t envy the complications that can arise with two mic’ed instrument in a live situation, but let’s assume a clean preamp’ed signal for each.
Spitballing here, because I never used two instruments into one H90, without some kind of mixer & sends involved. Easy to set up ‘one or the other, maybe both’ going through both Presets, but more hardware involved.
You don’t mention stereo use, so I’m guessing one input for sax & the other for guitar in an Insert routing. This might cause you issues with some effects, by pushing sax & guitar to the left & right inside further processing.
What you could do with Insert routing is use the sax / Mixing Link in the main path, and use 3/4 as an insert to it with the guitar (or vice-versa). That way, you have a lot of options for where you place the inserted instrument versus the Preset locations.
Dual Routing could work. Both Presets on one or the other path, baked into the Program itself. That would involve switching between two Program semi-duplicates for instrument change-ups, but eliminates the ‘maybe both’ scenario.
Or perhaps I’m just overthinking it (away from my H90s) and there’s a simpler method. Certainly an active ABY switch or LS-2 before the inputs is another solution.
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