Just for some info up front...
I am running my KPA thru the Main Output via XLR to FOH at a set level of -18.0 dB. I am also running the speaker out to a 2x12 cab with the cab sim off and using the Power Amp volume, which is unlinked, to adjust my stage volume as needed.
Ok. Here is my issue and questions:
Today I was adding some effects to a few performances via a mono loop slot using my Eventide H9. I was listening to the KPA thru my DAW. I hadn't checked any effect output levels on the H9 at this point yet but everything sounded great.
Next I turned up my 2x12 to check how the performances would sound on stage the same presets that sounded great thru the Main out had moments of overloading/digital remnants thru the speaker out. So I went to the H9 and lowered the output and the overloading sounds went away. While checking the levels I realized that the overloading was even happening on performances where a loop slot didn't even exist. I would turn up the H9 output = distorted. Turn H9 output down = no distortion. Again, no Loop Slot in the performance slot at all but the H9 levels seem to be effecting the signal.
I understand that as long as I level everything correctly I will be fine thru both outputs but I would still like to know:
1) Why would the signal coming from the Main Output to my recordings never overload even when the H9 was peaking and the speaker out signal was overloading/distorting?
2) Why would the Speaker Out overload/distort even when a Loop slot doesn't even exist?