Krell KAV 250 A

Bryan certainly makes a good point. Not being familiar with this 300i piece myself I don't know if in fact there are outboard connectors that allow separating the preamp stage from the poweramp section; in fact these connections may not even be available at the rear panel, but only inside. I had previously checked on Krell's website, but I don't see it shown there.
Certainly any stock power cord will allow a component to play music, but not at its' optimum by any means. Just stick with whatever you're comfortable with for the time being; I only mentioned this because if I had kept my 250a & tried to tweak it with better cabling, then I might not have ever sold it. But I didn't believe in any of that "nonsense" either at the time, & probably made a mistake due to my ignorance.

This is just something to think about, you have a $15,000 speakers I suggest you sell the 300i and buy an FPB series amp (since you like the Krell sound, so do I mind you) and a very good tube preamp. Then you'll hear what your speakers can really do.

here's another issue: was thinking that if the 300i does not externally link its preamp output section to its power amp input section, then you have no external access to variable-level preamp output to drive an external power amp anyway. You cannot use the tape monitor output (even if available) because it runs at a fixed level, but you need variable of course.

Bring this one back from the dead...

The KAV-300i has single ended pre-amp out connections but the binding posts are ALWAYS live.

Now, could you bi-amp a pair of speakers, using the 300i for the highs and a 250a for the lows?

Just got me a used 250a so we will see what I can do with it.