any krell power amplifier users use tube preamps?


I was wondering if any krell full power balanced amplifier users 300c, 400cx, or 700cx owners use tube preamp? If so, I have a 400cx and am in process of buying on audiogon a high end BAT tube preamp. I am concerned that even though both Krell and BAT told me in emails that I sent them that the BAT will work fine with the krell amp, the krell 400cx manual states that prior to using a tube preamp one should have a krell dealer activate the coupling capacitors.

Well I bought the Krell on audiogon and so it would not be so easy to get a krell dealer to do this for me. Besides, the krell amp weighs a ton and can only imagine would require a krell dealer service person to come to my house!

Thoughts? Comments?


p.s. thanks in advance


I have Krell amps but I don't use a tube preamp with them. You can remove the jumpers in the amp yourself. You don't need to send it to Krell or need a dealer. Just remove the top cover and you'll see 2 jumpers on a small PC board located near the input connectors. The jumpers are next to a couple of small yellow color capacitors. By removing the jumper, the capacitors becomes in series with the input and blocks dc from the tube preamp.

Call Krell and they will either tell you how to do it, or fax you a sheet on how to do it. A few years back I had a FBP200C that I was using with my BAT VK50SE and it was great. It's no big deal to remove the top of the amp--heck I did it! Good luck and enjoy.
I am using Sonic Frontiers Line One, planning to get a decent Line Two or Three for upgrade. A good match with Krell power amp performance.

I am using FPB200 right now.
I used a tube pre Audio Research LS-16 with an FBP-300 and FPB-350M amps. The tube pre added a nice warmth to the Krell SS slam.

Be sure to address the jumpers before you connect a tube pre.
Some tubed pre's put out excessive D.C. and some don't. I've used a CJ ART2 into a Krell 600c without the coupling capacitors engaged. CJ told this degrades the sound.
I have a AR REF One MK 2 that I'm about to hook up with a recent purchase of Krell 350 mc's. Does anyone know if the Ref one puts out excessive DC. I'd like to leave the jumpers in if I don't have to remove them.


JOhn Cusick