I have ran the Portico > AD-500 rig a few times now, all with not so great results. I have been keeping the AD-500 levels at zero, and have tired many different levels on the Portico. In short, my levels have always been too low (peaks around -5.5 dB), often the peaks were all chopped off at this level, like clipped sectors except not close to 0 dB. I did some testing, and re-read the AD-500 manual and now think it must be related to a maximum input level on the AD-500 stated as:
(front panel gain controls at minimum, fully counterclockwise)
+28dBu balanced, +24dBu ubalanced
I feel like an idiot for not figuring this out sooner. Anyway, it seems like I will need to have levels adjusted on both the Portico preamp and AD-500 A/D to get reasonable levels. Is this correct for all variable gain pre amps run in font of the AD-500? Any tips/pointers on getting the perfect balance? I would ideally like to run the Portico as hot as possible without causing the psuedo-clipping. Thanks!