First bi-amp go around

Hello wturkey, You’ll likely have quite a few responses explaining about matching input impedance as well as the differences in type/design of amps...cabling used... individual differences in driver efficiencies and an array of other variables; all of which are important factors to be sorted out. But: you’ve already experienced the most profound effect of doing it ( and you’ll 
be able to refine it all even more when you address these other factors more closely) : the biggest improvement imho is the 
A M A Z I N G    S E P A R A T I O N. of the instruments... it’s really a kick.
I’ll watch for further responses... it’s a cool trick if you can pull it all together. Ideally of course you should have identical amps... and if they’re all mono blocs... the individual localization of stage is incredible...
Have fun.. just be extra careful stepping through the additional maze of cabling!!!

Forgot to add the other factor making the whole scene [if you can pull it all together] even more addictive:
the sense of effortless power ... the feeling that no transients /  ‘peaks’ or demands are ever any ‘effort’... it’s just instantly reactive... instantly available...
You will actually seek out the most demanding material you own and [ if your speakers can handle the challenge] you’re going to say “ WOW”! often!

Definitely agree with the effortless power statement. Peter gabrial new blood was being played. I was listening while doing other things. There were many moments while listening to this album, for the who knows how many time, I thought "what was that?" Upon first investigation, it seemed the ps audio bhk preamp was unable to do two preouts. After actually reading the owners manual, it IS designed to handle two pre outs. The only real hangup setting this experiment up was the xlr to rca patch cable needed as both of these types of amps are single ended. 

The result. WOW! Very big improvement. If anyone has ever contemplated attempting bi-amping, I highly suggest it.

There are two ways of passive bi-amping.

1: If you have two different stereo poweramps amps, the only way is horizontal bi-amping, put the best sounding one on the mids and highs, and the one with the biggest "nads" on the bass.
(But you need to have a volume control (passive) on the amp that has the highest gain so you can reduce it to equal to the other amp in level (gain), then use you preamp or source as the master volume control.}
http://www.av2day.com/wp-content/uploads/2014/05/biamp1.jpg

2: This is the best sounding way. If you have two identical amps then vertical bi-amping is the best, as the power supplies of both amps are available for both speakers for bass duties, and this is what should give superior bass control as well. (And no need for level control on one as they are the same gain.)
http://www.av2day.com/wp-content/uploads/2014/05/biamp2.jpg

Cheers George

Yes, the current setup is utilizing the horizontal biamp setup. Also yes I have the more powerful units driving the woofer. In the basement is an old silverface receiver that I always enjoyed the sound of. I may swap this unit in at some point and see how the sound changes.