I can think of a half-dozen things that it might be, but let’s start with the simplest one first. It sounds like you have the Routing thing down: Global setup first. Then the Wet / Dry options become available (per-preset) under the H9 Control “More” dropdown. If – for example – you’re using my Room preset above, I posted that before we started discussing a Wet / Dry routing. Try this one instead:
This is what I meant by “You’ll still have to … adjust the MIX levels …” I have MIX pegged at 100% here. If you have a decent amount of delay time on the Echoplex, you should get a nice ‘bounce’ from right to left [Marshall to Fender / Dry to Wet]. -Or- H9’s PRE DELAY parameter can also get you that “Whole Lotta’ Love” spatial effect.
You can adjust the wet signal / dry signal balance on the two amps themselves, or with the Output Level control in the H9. I boosted this reverb-only preset here by 6 dB, as an example. Use the H9 Control Input Gain and Level Meters. They help out a lot in gain-staging effects. Note that this screenshot has the expression pedal mapping at the Toe position; in case you’re wondering why the REFLECTION parameter shows a different value.
If it’s not preset MIX position, then there are a few other options to consider. I did program these presets to be rather bright & bouncy. Perhaps a bit too much. I understand that Sunset Sound was a converted mechanic’s garage, and the upstairs reverb chamber was imperfect enough to sound just perfect.
