I put a passive line stage in my tape loop - for casual listening i have remote control also. works fine. When i'm feeling picky about sound i simply flip the switch turning off the tape loop. If you can accept some minimal signal loss (there will always be some) you can put a passive preamp of high quality between your amp and preamp but you must deal with the cable between the passive and the amp carefully to minimize the loss. I've done this with some success - not as funky as it sounds, but you'll get booted out of the audiophile corp if you tell anyone you did it!
