IMHO, an integrated is the perfect spot for a passive pre. You know the designer designed the amp section to work well with a passive pre, and you've decreased the parts count (and another interconnect) and therefore likely the overall expense to a great degree. A passive pre with a separate amp gets a lot more sketchy in finding a good combination. Maybe Ralph can chime in again and share what characteristics you need in an amp to be a good candidate for a passive pre. My only thought is if the amp manufacturer also makes passive preamps, you're probably in good shape. I'm thinking McCormack as an example. But an integrated makes a lot of sense if it gives you the power you need and the sound you like.
