The Signature is a total re-design to the standard 805. The mid-bass driver has a copper-plated pole piece to lower inductance, thus necessitating a bigger magnet to make up for the increased magnetic gap, and benefitting with more control of the driver. The resin used to control kevlar stiffness has been looked at as well. Distortion is down 60% to 0.15%.
The tweeter is identical to that used in the Signature 800 and is 6dB down at 50kHz. The pole piece is silver-plated to also reduce distortion, the coil former is shorter and lighter, and they've improved the crown structure. Hifi News claims a huge improvement over the standard Nautilus unit: far greater range, smooter yet more detailed, and far more refined.
The crossover uses a distortion-free air-core (formerly iron-core) inductor with Caddock resistors: they took an entire year to decide on those. The cross is up from 3kHz to 4kHz, so the tweeter's not being driven as hard at the bottom of its passband.
"Superb integration and incredibly refined", "a landmark product", and "the best B&W we've heard" are some of the reviewer's comments. And they look damn sexy!
Poorguy, what's your amplifier?
