Maybe I'm missing something but the main outs are line level only right? It would be nice to have a DI built into the unit to knock the signal down for live use. Some sound engineers have been giving me a little slack on that.
I can say that I profiled my HK MKII and it sounds dead on! I have used IEMs live for many years with the same amp and know what it sounds like close mic'd. Half way thru the first show I forgot that I did not have my head and cab behind me. Amazing product blows the Axe-fx out of the water!
...sorry, I don't get it. If you want to knock down the main outs just reduce the master volume, it goes 'till -95 db before to get silent. Did I understood right your question?