Tube amp

@luvrockin   Very familiar with your 801s, all 3 of the series. I do not question the use of a tube amp, but ime, as Charles indicated, always driven with beefy ss. Are you happy with your system, musically ( not talking visually ) ? I have always recommended with the series 3 vertical biamping.

@Mrdecibel, First off to answer your question, I love how my system sounds and I'm very happy with it but I'm sideways looking for ways to improve. I guess I always like to mix things up a bit being the fact I love the hobby and like to play. I never considered biamping for a couple reasons. I really don't know much about it. Also, I'm sure the cost would be pretty substantial. My preamp has on two balanced outputs for left and right. There is one for center as well but wouldn't use that. How would I bring signal to a second amp? I'd have to purchase another set of interconnects, speaker cables which I'd think would have to match? What a suggestion for a second amp for bi-amping. I have a Levinson 23.5 which puts out 200wpc. Would that be used to power low frequency or high? How much power would the second amp have to be? 

When someone says to me, "they are happy with their system", but are always looking to upgrade, this tells me, they are not happy with their system, whatever that might be. This is fine. The audio roller coaster never stops. Vertical biamping is when you have 2 of the same stereo amplifier, with each one driving just 1 speaker ( an amp channel for the woofs, the other for the mid/tweeter ). High quality y connects are available, but, you would need additional ics and speaker cable. IME, this gave me the best results. Horizontal biamping, as you are speaking of, is also common, but using a 2nd of the same amp is still preferred ( for many reasons ) imo/ime. Impedance, sensitivity and gain would be critical, for the 2nd amp, whether used for bottom or top. I understand the upgrade bug.

Most of the 801s I've seen work pretty well with tubes, although you need some power to make them go, but in that regard 100 watts seems like enough. We have several customers using 801s, mostly using our MA-1 amplifier. So that sounds like a pretty tube- friendly speaker to me.

I use a 38-watt tube integrated on enormous vintage B&Ws that are 91 dB efficient and dip to 3 ohms in the midbass.  The speakers were certainly designed to pair with high-current, high-wattage solid state.

The combo works for me, though I don't have a lot going on below about 50Hz.  If you can live without low bass and midbass slam, tubes may make you very happy.  My imaging and detail retrieval does not suck.