Bi-amping solid state & tubes?


I just got a pair of BAT VK60s to drive ProAc 3.8s, but I miss some of the bass from my old amp (KSA200s). I was thinking of bi-amping the Krell on the bottom and the BATs on the mid/highs, but have been told it would cause more problems than it would solve. How do I do it (any special modifications or hookups) and what are the pros & cons? Is it too much juice - it would be 320 watts/side and the speakers are rated for 50 to 250?
markvollmer
Biamping with 2 sets of the same amplifier is already complicated and very difficult to get proper results. I know your speakers very well. I do not think that you will be satisfied with the results. It's impossible to get the BAT and Krell to mesh sonically. You will end up getting a discontinuous sound even if you manage to get the levels of the amplifiers right. The diverse tonal balance of the these amps will be most evident on instruments like Cellos that have a wide frequency range. You will hear half the instrument sound like tube amps and the bottom end like Krells. There are other amps out there that will give you a much more musical sound and a proper deep full bodied bass that you crave. You ought to listen to the Lamm ML1 amps. They have the most musical and neutral sound of any amplifier with truly realistic, fleshy bass. It's also a great match to the Proacs. rgds, david k., damokanyc@aol.com
I had tubes and didn't have much bass then I had solid-state and didn't get the warm mids. I bi-amped them and got agood sound but something was still not quite there. I went to Cary SLM200s got a great sound but the bass was still a little thin even with this high power. My troubles are now over after buying the Wolcott Presence monoblocks. They have 250 watts with a high damping so you get bass like a Krell and superb mids and highs from the tubes. I think this is what your listening for. Take a shortcut and audition the Wolcott Presence amp.
Can't tell you what your response would be with this setup but if you have both amps then trying it out is a breeze. Just get a couple of splitters and run one set of each side to each amp. Use the R/L of the KSA for bass, the R/L of the BAT for tweeters. You'll need two sets of speaker wire (one for each amp) and your speakers will need to be bi-wirable (have four binding posts on them). You'll also need to remove the jumper strap that's on the Proacs now if you're not already bi-wiring them. The only concern you have is gain mismatch. In other words, the gain in one amp may not be the same as the other. If this is the case you'll have to build a little resistor network to cut the signal at preamp output to the higher-gain amp to make the two equal. Otherwise the bass is going to sound louder than the tweeter, or vice-versa. Call BAT and Krell and ask them the gain on these amps to see if they are close. As far as sound goes, I've heard quite a few people who have done this with differing results. Some said it just wasn't a match, some absolutely loved it. I don't think anyone complained that it ruined anything. As for the power rating, as long as you don't turn the preamp volume knob up to 11 you'll be fine. Shawn Harvey