Bi-Amping Options B&W 801 Series 2


New to me Bowers & Wilkins floor-standing full-range monitors with two sets of binding posts.
Currently have dual MC252 solid-state amps (with autoformers) connected as follows: (1) to both bass drivers and (1) to midrange and treble drivers.

Meanwhile, I have a Rogue Audio Stereo 100 sitting idle (although I could hook it up to my vintage Warfedales). I’m wondering if I would be better served by bridging both the MC252s and putting them both on bass duty (500 Watts to each driver), and put the Stereo 100 to use driving the midrange and tweeters. What do you think?

Especially interested to hear from someone with experience driving this particular speaker, which sounds wonderful, by the way. My system is fully described (but not well pictured) under my profile in Virtual Systems. And, if anyone has a lead on an original Bass Alignment filter, I’m all ears.

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For biamping you’ll need an external crossover or passive volume device to match the gain between top and bottom drivers. Is that what the Shiit Freya is for or can this be done with the Mac control processor?

You have a beautiful system, btw.

tomcarr is mistaken; your speakers do not dip to 3 Ohms; they have a minimum impedance of ~ 5.5 Ohms at ~ 10 KHz. This speaker has very benign impedance and phase angle curves which make for a very easy to drive speaker. Regrettably, I consider tomcarr to also be mistaken in stating that they need current. At chez xeno, our North Creek cross-overed Matrix 801 Series 2 speakers are driven by 75 lb. custom tube monoblocks that use 2 BL7 and 4 KT77 tubes, making about 100 watts. The system can play much louder than I would ever want.

Suffice it to say, I agree with russ69, try the Rogue 100. I bet it sounds great :).

Saw your system photos; I’m curious about your 801’s crossovers; what are they? They look great...good for you for upgrading from the week link factory x-overs. Oh, and forget about the bass alignment filter, at least the B&W one; it steals the incredible detail that these speakers have without it. The Krell version is thought by some to avoid this problem, I don’t know, but I do know that I’m not willing to put anything between these amazing speakers and our amazing amps other than Silversmith’s amazing Fidelium speaker cables :)

Enjoy your great speakers!

 

@russ69 A single MC-252 got better highs and better lows than the Rogue Stereo 100 from the Warfedales, in my opinion. I had issues with very dissonant distortion from an Electric Light Orchestra recording when running both the Freya and the Stereo 100, although the main issue was with my cartridge & Numark turntable & arm, as I recall.  Taking the Freya out of tube mode removed the distortion. I actually came to prefer the buffered mode for the Freya. 
The B&W have a lot more top end than my vintage Warfedales, ARs, and KLH models, so I was thinking that with the B&W speaker, I wouldn’t mind a bit of roll-off on the top end. 

@raysmtb1 I am using at least one tone control now, the ‘Environmental’ equalizer McIntosh MQ-107, and although I haven’t attempted to ‘curve’ it as yet, I am boosting the bass at ‘2’ out of 5 or 6 (I can’t recall exactly), but I’ve had to turn it down from ‘rattling the windows’ on some recordings. I would say you’re correct, although you can hear the bass without the EQ boost, you can hear it a lot better with it. 
More to your point, I’m not sure what more power will do for me. The manufacturer describes the bass driver as “12 inch (300mm) high-power polymer-cone woofer,” and I have read comments about what a nice speaker it is (was), but that it required a lot of power. When I have it turned up to ‘loud’ I’m 21 dB consuming about 25 Watts. But the amp experts always talk about having enough reserve in either the choke or the capacitor bank to deliver high amounts of current in a short amount of time to properly deliver the ‘transients’ that make for dynamic playback. 
But I think the also say that twice the power takes ten times the Watts, so . . . how much is enough, and how much is too much? That’s kind of my question. 

@tomcarr I like the way you think. I’m probably goin to try it, regardless, but I thought I would ask the question here, to gain knowledge from experts and those more experienced than myself. I’ve got a good deal of money tied up in the system at this point, so there isn’t a lot of room for ‘playing around’ in ways that failures go in the trash can. Ben there, done that, got the T-shirt and a few damaged amps and speakers to prove it. :-)