Biamp question

Oldhvymec thanks for your advice and input. I will give that a try. Thanks to everyone else who commented for your input as well. This has all been quite illuminating. 

I do have one last question. I am assuming that both amps inputs go to the same preamps outputs. Is that a correct assumption?

You do not need a crossover- just let the speaker do the work. 

connect the bass amp to the bottom speaker terminals and the mid/treble amp to the top set of terminals. 

you may have a gain issue that causes a miss-match- 

You would need an RCA Y-cable to spilt the preamp signal.  

PS I have owned the a21+ and the Stereo 100.  Have you tried just the stereo 100?  I found it as powerful as the a21+ and your speakers are very efficient.  Try just the ST 100 if you haven't.  

Yes just split a full signal out to your preamp to you SS and Valve power amps. RCA or XLR. What ever you use.

Enjoy..

Thank you all. I have not tried the st 100 by itself yet. Are you saying that not only is it stout enough to drive the bass on the legacy’s but that you also prefer the sound of st 100 over the a21+?