Hi Robert
I'm not sure the FX Loop runs on a fixed impedance or is automatically changed when input level is choosen between 0/-10dB.
Anyway I do not use the fx loop. My mixer takes care of the whole thing.
A PSA-1 XLR output goes straight to the mixer for dry sound, panned center. The other runs to Eclipse input 1. The Eventide input mode is set on Mono 1 (that makes the unit mono I/stereo O). Eclipse XLRs outputs connect to 2 mixer channels, hard L/R panned for 100% wet fx only path.
Eclipse doesn't need line/instrument level switch as, like all Eventides rack units, it uses 1/4" for instrument levels and XLRs for balanced/unbalanced line level connections.
This configuration works very, very well for me as it keeps the 2 signals paths as sonically pristine as possible, with great level amounts.
best
I
