Splitter -- One preamp to two amps. What to use?


I need your help! If people are bi-amping, How are they connecting from their preamp to their two amps and to their speakers?

I am currently running my NAD 1700 preamp with two separate outputs. One is a Lab unfiltered RCA out which goes to my Mid’s and Highs into one of my NAD 2600 amps. And I have a second RCA Normal, which is lower fidelity which runs thru another NAD 2600 into my woofers. I then run two sets of 10 gauge Blue Jean cable to each speaker. What I would like to do us upgrade my speaker wire ( AudioQuest Redwood or DR Acoustics Red Sky Bi wire ) which are bi-wire cables and bridge my amps to achieve 450 watts per channel.

Here is the problem. In order to do this I need to split the one output from the Lab RCA on my preamp to feed the two separate amps. I am currently using Audioquest Waters and hate to put something inline that is a lower quality than the Waters.

I can’t believe I am the only one with this problem. How are the smart audiophiles addressing this problem?
captaindidactic
To do this correctly your preamp should be plugged into an active crossover like The JL Audio unit which would then have separate outputs for the woofer and treble amplifiers. This gives you control over the cross over points, phase and amplifier gain. 
I forgot to mention that you can also bypass part or all of the passive crossover in your speakers which in many if not most cases will improve the sound and imaging. 
yogiboy  
I thought about the Y adapter, but I am wondering if that will degrade the sound by putting in an inferior jumper in the middle of the line. 

mijostyn
Sounds Intriguing, But how do you bypass all the crossovers in the speakers? My big Acoustic Research TSW 910's are 6 way speakers. Also, from a purist standpoint ( fewest things inline is better ) How does an active crossover change the sound? Or is it like everything else...Try it and see??
Maybe I missed something, but if you are bridging your amps then why do you need a splitter at all? If I read it right, now you have 4 channels of amplification by running each amp in stereo, one for HF one for LF. If you bridge your amps to mono then you will only have 2 channels, that you can then bi-wire if you so desire.