Bi Amping my B&W Matrix 800s


I have been thinking about bi amping my B&W 800 Matrix . I am now using a Krell FPB 600 with a Mark Levinson 38s preamp and a Krell B&W 800 Series bass Alignment Filter. With the B&W Matrix 800 speakers being quad wired. I have been considering buying a Krell FPB 300 to bi amp with my Krell FPB 600 using the Krell FPB 600 for the 4 woofers (2 on ea. speaker) on my 2 B&W 800 Matrix and the Krell FPB for the tweeters and midrange on ea. B&W 800 Matrix . Can this be done with my Mark Levinson 38s preamp? Would bi amping really do justice for my B&W Matrix 800s? And how difficult would it be ? Thank you all .Mike 
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There may be 4 PCBs but the 800 is essentially a 3 way with multiple driver arrays.  The 802 is also a 3 way but with 2 LF drivers.
I purchased my 802s new in 1992.  They were not overdriven.  Caps, even polys, dont hold their specs for 20+ years.  Best way to see is if you measure their ESR.  Also, if the 800 is anything like the 802, they used cheap Bennic lytic caps.
The passives on the 802s were a bit easier to remove and replace.  I did it myself.  Used Mundof caps and Vishay resistors.  Did not use polys for the electrolytics.
On my 802s, there are 2 PCBs for each speaker that make up the passive crossover, one for the LF and one for the MF and HF.  I replaced the capacitors and resistors.  But then I went with active crossovers for the SW, LF, and the MF/HF combo.
cleeds and edwyun  No sorry there are 4 passive crossovers in each 800 and they have polypropylene capacitors. They do not absorb moisture and they do not store heat. They will last longer than you. Those speakers were over driven by users . Im sure they were abused or you inherited bad speakers. 
tattooedtrackman
There are 6 active crossovers on a pair of B&W 800s ...
Are you sure? I'm fairly certain the 800s use passive xovers.

There are 6 active crossovers on a pair of B&W 800s. What did that cost you to replace or recap. And how hard is it to find a reputable B&W service tech who would do this. 
Also they are no joke to take apart and put back together especially when u live alone. 
Mine looked great too.  But they did not measure well on the LCR meter.  I replaced them and I recovered  some better low freq response I didnt know I had lost.  These matrix series were built in the late 80s to early 90s so that is not unexpected.
edwyn when i put my 800s together and the caps in the passive crossovers looked great. And they sound fantastic. So how can you tell me they need replacing? 
And even if you keep things as is, the caps in the passive crossovers already need replacing.
I would only recommend it if you used active crossovers.  No issue with coherency whatoever.  Thats just a red herring.  Ive been triamping my Matrix 802s and subwoofer for many years and couldnt be happier.
There is NO sonic benefit to biamping your B&W 800's over what you have! Adding an active crossover and amp will only disturb the coherency between the drivers that B&W so carefully designed! 
Im really also concerned if i can use my Mark Levinson 30s preamp to bi amp . I have a R and L balanced main out XLR that is hooked up to my Krell B&W 800 bass alignment filters 2 , balanced. And my R and L balanced input 1 is going to my cd player. Which leaves only the R and L balanced input 2 . But i still have R and L main out RCA still open. Any suggestions as if i bi amp with my ML.?