Well, it' a long story but I'll try to keep it short.
If you click on my system you can see some pictures of my present system turmoil. I am at this time forced to use the digital-out from my Technics Dvd A-10 into the DAC of my Sunfire theatergrand pre-pro. When I had the Bent passive pre in the system I had the Sony XA-777 sacd player in the system also. I sold the Bent and the Sony to help pay for a complete speaker system change-over: Going from all VMPS multichannel system>all Apogee multichannel speaker system.
The new room should be done soon and I will be adding back into the system another higher quality cdp and another higher quality two channel pre.
As far as the kav-300i, I have never listened to that unit. I do have a kav-500 amp that I use on the top of my bi-amped Duetta Sig's..it's a great sounding amp for that use but does not have near enough power for difficult to drive loads. The Kav series of components are very good..but are built to a much lower standard than other Krell gear, for instance: the Krell Kav-250 is a great sounding amp with plenty of power for most use, except difficult to drive loads. This is the amp that causes the word bright to be used in context with Krell, it's not a bright amp at all. People see the name Krell on it and assume it will do what the other Krell's will do..that is: drive any speaker system with-out strain. It won't, it can't and it does not, it clips and sounds bright.
I've found that pre-amp have a greater effect on sound quality than amps (unless the amp is of poor design or not up to the task of the job given it). The Ksa-250 is said to sound great with tubes (I have not tried them). It's a great match with passive in most systems (it was in mine) and should be a great match with Krell pre-amp of your choice. How does the pre-amp section of the Kav-300i sound to you? Is there something you want more of..or less of? Is the soundstage to forward or to far-back? I know it's large enough so I won't ask that. Are you using balanced outs?
I told you I'd make a long story short?? Sometimes I can't shut-up.
Dave