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Definitive Technology SR-8040BP

Bipolar surround speaker

34 Reviews

Item #: 735SR8040

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Definitive Technology SR-8040BP


Our take on the Definitive Technology SR-8040BP

Experience that "I'm there" feeling on your next movie night with Definitive's SR-8040BP bipolar surround speaker. It contains left- and right-firing driver arrays that radiate full-range sound in an omni-directional pattern — you'll really hear the difference as on-screen action shifts seamlessly from one side of the room to the other. Part of Definitive's Bipolar Series, it combines advanced driver design and sturdy construction to give you exceptional detail and presence with ambient effects and multichannel music.

Bipolar design creates wraparound sound

Definitive Technology SR-8040-BP

Experience that "I'm there" feeling on your next movie night with Definitive's SR-8040BP bipolar surround speaker. It contains left- and right-firing driver arrays that radiate full-range sound in an omni-directional pattern — you'll really hear the difference as on-screen action shifts seamlessly from one side of the room to the other. Part of Definitive's Bipolar Series, it combines advanced driver design and sturdy construction to give you exceptional detail and presence with ambient effects and multichannel music.

High-tech drivers for exceptionally detailed sound

Each driver array in the SR-8040BP has a 3-1/2" midrange paired with a 1" dome tweeter, for perfectly blended highs and mids. This bipolar design creates a big, immersive soundfield, which is really effective for surround speakers. Each pure aluminum dome tweeter has a silk surround, allowing it to reveal delicate, low-level ambient details in soundtracks. And thanks to Definitive's Balanced Double Surround System (BDSS) drivers, your movie special effects and multichannel music will sound clear and detailed. These mid/woofers disperse the sound over a wide area in your room so that even viewers sitting off-axis hear smooth, engaging sound.

Versatile placement options

Definitive's bipolar surrounds aren't fussy about placement — they shine in a variety of room sizes and shapes. A pair of SR-8040BPs works well on your side walls for 5.1 systems, or on the side and rear walls for a 7.1 system. Each speaker has a keyhole slot for on-wall installations. You can also place this speaker on a shelf or stand and get great results.

Build a complete Definitive home theater system by adding perfectly matched bipole towers (see the BP-8020ST, BP-8040ST, BP-8060ST, and BP-8080ST) and a center channel (see the CS-8040HD, CS-8060HD, and CS-8080HD).

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Did you know?

Your new speakers will probably sound better after several weeks of use than they do right out of the box. That's because the material surrounding the woofers will loosen up, allowing the drivers to move more fully. Definitive Technology estimates a break-in period of 24 to 48 hours of playback before the speakers will deliver optimum sound quality. For more information and helpful tips, check out this article from Definitive's website about conditioning your speakers.

What's in the Box:

  • One black full-range bipolar surround speaker
  • 2 Grilles
  • Owner's manual
  • Online product registration information

Product Highlights:

  • Linear Response Waveguide™ for wide dispersion and smoother sound for listeners sitting off axis
  • Balanced Dual Surround System (BDSS) driver technology places rubber surrounds on both the outer and inner edges of each speaker cone for improved clarity
  • frequency response 50-30,000 Hz
  • sensitivity 92 dB
  • 8-ohm impedance
  • handles up to 150 watts
  • left array: 3-1/2" mid/woofer and a 1" aluminum dome tweeter
  • right array: 3-1/2" mid/woofer and a 1" aluminum dome tweeter
  • one set of 5-way binding posts
  • high-gloss black finish on top and bottom caps with cloth grille-wrapped enclosure
  • 7-7/8"W x 9-5/8"H x 5-3/8"D
  • weight: 8 lbs.
  • warranty: 5 years
  • Our 60-day money-back guarantee

Definitive Technology SR-8040BP Reviews

Average Customer Review:

34 Reviews

Def Tech SR-8040BP BIG SOUND/small package

The Amazin' Zoltar from Warwick, NY on 3/26/2014

Crutchfield Customer Review (What's this?)

I needed to replace a pair of blown M5 Polk speakers that had been used for 20+years as rear surrounds in a 5x1 system. The old Denon high end receiver has a legitimate 140RMS X5 power rating. I did not want a big speaker and wanted as full of a sound spectrum as i could get. The specs of these bi-polar beauties were within the realm of what i was looking for. I took a chance, spent the money, and am happy with the purchase. One rear screw slot mounts these small, all black speaker to your wall/mounting plate. Used as surrounds, they were definitely just what the doctor ordered-and are better performers than my original M5 Polks were. I think you'd be happy hearing the ocean, birds, crowd noise, and ambient gunshots that these bad boys can produce with aplomb!

Pros: Great small surround speakers that hide unobtrusivly in any room. Easy to install with one screw. Big sound for average home theater room dynamics.

Cons: Not inexpensive.


Gary from Rogers, AR on 2/6/2014

Crutchfield Customer Review (What's this?)

I got these surrounds with the package deal from Def Tech when you bought 2 8060 towers, and originally i used the towers with my ProMonitor 800 speakers as surrounds. I noticed pretty quick the 800s were outmatched by the 8060 towers under heavy action in movies. Once I finally got these installed I was amazed by the difference with these compared to the 800s. I still believe the 800s are great speakers, but these produce way more sound.. The sound quality is exactly what you'd expect from Def Tech.

Pros: Great surround speakers..

Cons: Not really a con, but be sure to note these are 8lbs.. I missed that when i purchased these, and had to rework my speaker mounts. Not a huge deal, but just something to keep in mind. A couple Hangman Double Headed Bear Claw screws, and i had them up on the wall..

Great Side Or Rear Speakers

CarolW from Keller, TX on 1/28/2014

Crutchfield Customer Review (What's this?)

These are great speakers when used for side speakers or rear speakers. They just create a beautiful look with the Definitive Technology center channel and tower speakers. I could not be happier with this set. Top quality equipment!!

Pros: Quality sound, looks.

Cons: None.

great product

tom3jr from Waldwick, NJ on 1/6/2014

Crutchfield Customer Review (What's this?)

These speakers completed my package of Definitive Technology system.




Chris from Fort Worth on 12/7/2013

Crutchfield Customer Review (What's this?)

Excellent sound. Crisp, clear, good bass. I'm using these speakers as my side L & R surround speakers in a 7.2 setup. Pretty good sizing living room area, too. 16' x 30', with 10' ceilings. They do what they're supposed to do. From Korn & Metallica to Christmas music to Dark Knight Rises, they really do their job. Would recommend to anyone if they're willing to spend the money.

Pros: Look great. Sound great.

Cons: None.


Anonymous from hillsdale. MI on 11/13/2013

Crutchfield Customer Review (What's this?)

Excellent match to the 8060's I purchased.

Pros: Truly the perfectly matched surrounds for a seamless sound from front to back, using 8060's across the front.

Cons: None

Greate rears

Mrbill from los angeles on 3/31/2013

Crutchfield Customer Review (What's this?)

Love my speakers


Cons: none

Definitive Technology SR-8040BP

SW from rockford, il on 3/29/2013

Crutchfield Customer Review (What's this?)

Great sound quality for the price, works well as the single rear in a 6.1 setup.

Pros: sound quality

Cons: none

Worth every penny!

Dave from Discovery Bay, CA on 3/26/2013

Crutchfield Customer Review (What's this?)

I purchased these 8060 towers, the 8060 center and the 8040 surrounds. The 8040 surrounds are amazing. I wasn't too sure how the black speakers were going to look on the walls since our old speakers were small, white infinity minuettes. Actually it was my wife that was really concerned, but the 8040's look great, and the best part is, she agrees! They sound so much better than my old surrounds and they really have a classy, sexy look to them. My old surround speakers sounded good, but these sound amazing!

Pros: Great sound and presence for a surround speaker!

Cons: None!!!

Big sound from small speaker

dale G from St. Louis on 2/15/2013

Crutchfield Customer Review (What's this?)

Great sound from a little speaker. Solid build and finish.

Pros: solid build and great sound

Cons: speaker only has a keyhole slot mounting option.

Clean and Clear

Bid Daddy from Toledo OH on 2/10/2013

Crutchfield Customer Review (What's this?)

I forgot to review these speakers earlier. Bought the Def Tech package. These speakers do exactly what they are intended for. clear surround sound. they add spaciousness and even sound dispersion. this speaker set ROCKS. Movies are great and tunes sound fantastic. Will eventually move them to the sides to replace a pair of 1000 monitors and purchase the 8080's for the rear. You will not go wrong purchasing these speakers. They look awesome hanging on the walls.

Pros: Very nice sound quality. Easy to hang and connect. Looks sweet.

Cons: When wall mounting can not use plugs. no big deal though

8040 vs 8080

Mistawankaz from Syracuse, NY on 8/23/2012

Crutchfield Customer Review (What's this?)

First off. These were mounted to my wall easily and effortlessly. So I really have no idea how/why a previous review stated otherwise. My review is just a comparison of 8040 to 8080. The 8040 are the best backup speakers I could of asked for. I have the deftech 8080st and 8080 CR mid. I went with 8040 rears to see if it would really matter for the sound stage (in comparison to the 8080SR). The sound quality in a 13 x 24 foot room is just incredible. These "little" guys can really hammer out lows, and accent the ST's/CR amazing sound quality. This was of course only a 5.1 setup. 80's up front and the SR40's in back. After all this good news (and incredible sound quality) I finally decided to go from 5.1 to 7.1 (I wanted to see if a sale for the 80 or 40 SR would happen) I got the 8080SR for my rears and tossed my older 8040's for my right and left middle. For the extra $ per speaker I paid. The 8080's are worth it, lower lows are totally noticeable. But in nearly every aspect the 40's keep up surprisingly well. I would have no worry in telling anyone to get the 8040 SR over the 8080 everyday. Unless they truthfully feel the smallish boost in bass/loudness will bug them. The fact of the matter is, because they are rear/surrounds. They just never get pushed to the max, so getting a bigger all around rear/surround speaker could be $ down the drain. For anyone who doesn't understand. Get the 8040's unless you think you will notice the small boost from the 8080's

Pros: Best rear speakers I have ever had that are under 500$ per speaker. Generically easy setup/mounting to wall. Loud and clear. Look very stunning on the wall. Dual direction makes for the sound stage to fill the room easily no matter placement. For what they are the price is astounding.

Cons: None, but deftech should consider a price change (or calling this one the 8060 and inventing the 8040 as a even smaller speaker). They are worth the money, but the price for a STBP setup rears seem almost too much. If they offered some for 150-250 and 350. I could better recommend what ones to get to everyone. But right now saving the $ (per pair) by going with the SR8040 over the SR8080 is a no brainer. So I always recommend the smaller pair.

Amazing Surrounds

Chad S from Raleigh, NC on 1/21/2012

Crutchfield Customer Review (What's this?)

Order these Def Tech surrounds with the whole BP system, needless to say, they sound amazing. They manage to put out a very enveloping sound field. Mounting was pretty easy, just throw and screw in to a stud and throw the speaker on it, done.

Pros: Clarity Coverage Looks

Cons: Need to run in wall wiring if you plan on using banana plugs

Missing Wall-mount Hardware

Bob from Hurst, TX on 10/30/2010

Crutchfield Customer Review (What's this?)

These speakers sound very good, but be aware that they do not come with all the hardware necessary to mount them on a wall. This isn't really spelled out in the information on the speakers; in fact, they are advertised as coming with "an easy-to-use mounting plate for on-wall installations." The mounting plate is all they come with. If you want to find the rest of the hardware necessary for wall mounting, good luck. It seemed reasonable to me that this price would include all the hardware necessary for wall mounting. <br> <b>[Editor's Note: We apologize for any inconvenience. We have edited our web presentation to avoid similar confusion in the future.]</b>




Hands-on research

Product Research


Bipolar Design: The Definitive Technology SR-8040BP is a bipolar surround speaker, containing two full-range woofer and tweeter arrays. The speaker cabinet has three sides, with the driver arrays firing in phase approximately 100° apart to flood the area with sound (the third side mounts against the wall). Dispersing the surround channel's sound evenly over a broad area of the room creates an enveloping movie experience.

Drivers: The two woofers used in the SR-8040BP are 3-1/2" second generation BDSS (Balanced Double Surround System) drivers. BDSS is Definitive's patented technology that supports the speaker cone at both the inner and outer edges allowing longer and more linear excursion for greater clarity and detail. The new Linear Response Waveguide (patent pending) smoothes off-axis frequency response and disperses sound over a wide area. The two tweeters are pure aluminum domes, heat-treated to relax the crystal structure, then coated with a ceramic to produce extended highs. The Linkwitz-Riley crossover networks maintain a smooth output around the crossover frequency.

Voice-Matched: The SR-8040BP is a full-range low-distortion speaker which is timbre-matched to blend perfectly with all of Definitive's BP series speakers.

Binding Posts: The speaker terminals are gold-plated, 5-way binding posts and will accommodate spade connectors, single or dual banana plugs, pin connectors, and bare wire up to 10 gauge.

Mounting: The SR-8040BP is designed for easy placement; it has a keyhole slot for wall mounting, or it can be placed on a shelf or stand. It's designed as a surround speaker (surround or surround back channels), but can also be used for front effects channels in Audyssey DSX, Dolby Pro Logic IIz, or Yamaha DSP 3D (with presence speakers) systems.

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