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Bowers & Wilkins ISW-3 In-wall/ceiling/floor Subwoofer Preview

Bowers & Wilkins ISW-3 Sub

Bowers & Wilkins ISW-3 Sub


  • Product Name: ISW-3 In-wall/floor subwoofer
  • Manufacturer: Bowers & Wilkins
  • Review Date: August 04, 2011 05:00
  • MSRP: $1,000 (requires SA-250MkII amp additional $1000)
  • First Impression: Pretty Cool

ISW-3 Subwoofer

  • Drive units: 2 x 165mm (6.5in) Paper/Kevlar® cone
  • Frequency range: -6dB at 21Hz and 222Hz adjustable (EQ at A)
  • Frequency response: ±3dB 27Hz - 120Hz adjustable (EQ at A)
  • Bass extension: -6dB at 21Hz (position A), -6dB at 25Hz (position B), -6dB at 29Hz (position C)
  • Maximum Amp Power: 250W
  • Impedance Nominal: 8Ω (minimum 6.3Ω)
  • Dimensions: Width: 330mm (13in), Length: 470mm (18.5in), Depth: 235mm (9.25in)
  • Net weight: 12.5kg
  • Electronics (mandatory): SA250 Mk2

SA-250MkII amp

  • Description: 250W rack-mount amplifier with built-in subwoofer equalization
  • Amplifier inputs:
    • 2x RCA Phono socket, line in
    • 2x RCA Phono socket, link out
    • 1x XLR socket, line in
    • 1x XLR socket, link out
    • 3.5mm jack - 12V trigger on/standby (overrides manual standby setting)
    • 3.5mm jack - 12V trigger equalization movie/music
  • Amplifier outputs:
    • 1x Neutrik® Speakon® 4-pole speaker socket
    • 2x pairs of Binding Posts
  • Amplifier power output: 250W
  • Input impedance: 33kΩ
  • Signal / noise: >80dB
  • Rated power consumption: 95W – 1/8 full power, 30W – Idling
  • Dimensions: Height: 100mm (3.9 in) [88.5mm (3.5 in) plus feet]; Width: 430mm (16.9 in); Depth: 322mm (12.7 in); Front panel Height: 2U 88.1mm/3.5 in
  • Net weight: 5.4kg (11.9 lb)
  • Finish: Black

When dealing with people new to home theater, the most difficult speaker to get your head around is the subwoofer. The mains, the center, the surrounds... these all make sense. But that big box? Omnidirectional sound? Tactile bass that shakes the walls? Why do we need that again? To an audioholic, these questions have long been answered. For the new user, however, without the experience of hearing a good sub in their home, such questions are real and troublesome.

Now, take that person and give them a big pile of money. The first thing they'll want to do is hide the speakers. Either that or drop and truckload of cash on small, plastic cubes.

In-wall speakers are pretty common but in-wall subs are fairly rare. B&W is throwing their hat in the mix with the new ISW-3 Subwoofer - a speaker that can be placed in any wall of your house (including your ceiling and floor) and even has a right angle adapter for in-cabinet installation in a kitchen.

ISW-3 Cabinet

ISW-3 In-cabinet with Right Angle Adapter

When you are looking for an in-wall sub, you need a few things. First, you want it to be as invisible as possible. The ISW-3 has a small (2" by 12"), slotted grille that looks like an HVAC vent - something consumers will barely notice. It is small enough that it can be placed into the base or toe-kick in a bathroom or kitchen.

The sub features dual 6.5" Paper/Kevlar cone long-throw drivers in a balanced design eliminating transmission of vibrations through the enclosure and into the surrounding walls. When you install a sub into your kitchen cabinets, this is important as you're likely to aggravate your client if every time a kick-drum hits their glassware rattles. The ISW-3 is only 13" wide by 9.25" deep and 18.5" tall  making installation inside walls between trusses a breeze. 

In order to keep the size to a minimum, the ISW-3 was designed to work with an external amp. The SA250MkII is a required purchase for the ISW-3. It pumps out 250 watts of class D power, is rack-mountable, and has an external EQ switch setting for fine-tuning the bass response. The amp can be used with a dedicated subwoofer input from a receiver plus it has a stereo summing input for distributed audio applications.

When you consider the limitations of an in-wall/ceiling/floor/cabinet subwoofer, the performance is quite impressive. While B&W touts a 21Hz low end response, that's at -6dB. You're more likely to see real-world response in the mid-20's (rated from 27Hz to 120Hz +/-3dB). The ISW-3 weighs in at a featherweight 27.5 pounds.


The real question here is the price. At $1000 for the sub and another $1000 for the external amp (listed on the spec sheet as "mandatory electronics," sticker shock would be an issue except for the fact that there aren't a ton of products that meet this need. For $2000, you can get quite a bit more performance in a subwoofer, but you'll be looking at an in-room solution as opposed to a small vent in the corner of your room. For the custom installer, the ISW-3 configuration options and flexibility is likely to be a big draw. The only question will be performance. If the ISW-3 plays cleanly down to the mid 20's, the price and ability to hide the sub away is likely to be worth it. This is B&W, so we're betting it does very well given their history.

For more information, please visit www.bowers-wilkins.com.

Unless otherwise indicated, this is a preview article for the featured product. A formal review may or may not follow in the future.

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As Associate Editor at Audioholics, Tom promises to the best of his ability to give each review the same amount of attention, consideration, and thoughtfulness as possible and keep his writings free from undue bias and preconceptions. Any indication, either internally or from another, that bias has entered into his review will be immediately investigated. Substantiation of mistakes or bias will be immediately corrected regardless of personal stake, feelings, or ego.

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