B&W 802D vs Wilson WATT Puppy

The 802D employs a pair of 8 ohm woofers in parallel for an impedance of 4 ohms (roughly) in the range of the woofer (bass) region. The rest of the speaker is nominally 8 ohms. While you might think that a tube amplifier playing on this speaker is making good bass, it is a fact that most tube amplifiers would do a better job if the woofers were somehow 8 ohms with all other things being equal.

But here we are in the real world. In order for the 802D to make flat frequency response according to design, it must be driven by an amplifier capable of constant voltage response regardless of load; this means a transistor amp, as this characteristic is not associated with tube amps! IOW a tube amp will have shelved bass response (NOTE: *not* rolled off) as its output will be about 3 db less than anticipated by the designer in the bass region.

Some people hearing tube amps running this way will describe them as doing 'a fine job' but the fact of the matter is they can do better- they just need a proper load. My earlier point is that the Wilson provides a very friendly load for tube amps relatively speaking.

Atmasphere,

1. you are right on B&Ws sounding better w/ SS than tubes- 800N with AR tubes were the worst set up I've ever heard. very sharp observation indeed! :-)

a point to consider, though.
2. WP7's impedence plot shows that it too dips down near 2 ohms- stereophile sept. 2003
and JA also recommends a high current amp.. BUT you're still right that WP sounds better with tubes than the 800s with tubes ;-)

it is general notion that the wilsons are easier to drive.. (true for sophias) but.. could this be a marketing stuff?
the sensitivity and impedence are no where close to say.. JBL S9800 horns, which sounds FNATASTIC with anything....

looking at other measurement there are more resonance in cabinet and in the waterfall plot on the WP than say the old 801N or 800N... not to be a geek or jerk.. but I'm wondering where this superior midrange of WP is coming from?
I'm not trying to start a war or anything.. just MHO :-)

The WP7 has a 2KHz trap to deal with a resonance, resulting in an impedance dip at that frequency. As you might imagine, transistor amps tend to heat that trap in the crossover rather nicely, where in a tube amp the filter does its job rather well. Tubes have always driven the speaker fairly easily. Were that 2 ohms covering a spectrum rather then being a tight band reject filter, the speaker would be a lot harder to drive; the reality is it is easy to drive.

As far as which has the better midrange I am not commenting on that, merely that the impedance of the 802D points to compromising the bass performance of tube gear used on the speaker.

I say this a lot: if you are going to invest in tube amplification, your investment dollar is usually best served by a speaker that is 8 ohms or more (particularly in the bass region) all other things being equal. Tube amplifiers for the most part prefer higher impedances, and given what they are capable of, why not show them in their best light?

Why not use your ears not specifications. Almost everyone know that specifications are for technicians to see if the unit is working properly & have almost no reference to sound quality. You cannot measure detail,resolution,depth,imaging,sense of space. You can argue with specifications not real performance.
When is the last time you listend to live music?

Atmasphere,
yup you're right again :-)
ain't nobody's gonna make me drive my b&Ws with tubes .. :)

krellm7
I think specs usually translate to actual performances...especially when it comes to mating a right amp...
- I'm not a speaker engineer by any means...

and last time I heard the live music? a month ago..:-)

i love classical music, and I've been to say .. 100+ live performances and I think B&W speakers are quite (not 100% of course) faithful when it comes to reproducing the realism I get from the lives :-)

btw... I love your system.. the original matrix 800... AWESOME!
good day, gentlemen