Definitive Technology BP9000 Series 7.0.4 3D Immersive Audio Speaker System Review

Definitive Technology BP9000 Syspem with A90 Dolby Atmos-enabled modules

What defines a great 3D immersive audio sound system that’s based on freestanding speakers? Arguably, a well considered combination of refined aesthetics and high performance constitute a good start. You want a system that won’t distract from the screen when the lights are down, and looks good with the lights are on. The Definitive Technology BP9000 series 7.0.4 system featured here is one that easily fulfills those requirements.

Definitive Technology rose to prominence with speakers aimed at home theater market. It popularized the concept of combining an active subwoofer with passive drivers in a single tower. Mind you, Definitive’s speakers are also great for music, which is a topic I will visit in a different hands-on.

The benefits of using multiple subwoofers to smooth in-room bass response is well known to home theater enthusiasts. To that end, it’s pretty cool that this system includes four built-in subwoofers, spread out between pairs of BP9060 and BP9040 tower speakers.

Granted, one of the primary advantages of using a standalone subwoofers is that you can optimize its placement. You can’t do that when the sub is built into the speaker, but there is considerable mitigation of the optimal placement advantage when dealing with systems that contain multiple subwoofers—this one happens to have four. And since they are effectively hidden within the form factor of a tower speaker, Definitive Technology’s approach is among the stealthiest ways you can sneak multiple subs into your living room.

Okay, enough background on what these speakers are about. Let’s get going with this hands-on review!


This Definitive Technology 7.0.4 3D immersive audio speaker system consists of five models: Up front you’ll find a pair of BP9060 bipolar towers ($1099) handling the left and right channels, as well as a CS9040 center channel speaker ($499). The side-surrounds in this system consist of two SR9040 bipolar satellites ($299) and the rear speakers are BP9040 bipolar towers ($899). All four towers are topped with A90 Dolby Atmos-enabled modules ($499/pair).

Definitive Technology’s approach to its bipolar towers involves directing less acoustical energy to the rear firing drivers than to the front. The company calls this a “Forward Focused Bipolar Array,” and the goal is to add ear-pleasing full-range acoustical energy to the reflected sound in the room, but not overdo it.

Definitive Technology’s BP9060 bipolar towers are an 8-ohm, 3-way bipolar design featuring an integrated 10″ powered subwoofer. The company claims a frequency response of 18 Hz to 40 kHz for these speakers, with a sensitivity rating of 92 dB/W/m. There is an adjustable control that lets you tune the subwoofer level that lets you compensate for room gain and helps achieve a desirable tonal balance.

BP9060 tower speakers are effectively two-way bipolar satellites sitting on top of subwoofers. They feature dual forward-facing 4.5″ midrange drivers in a tuned, vented enclosure and a 1″ aluminum-dome front-firing tweeter. The rear-facing driver array gets a single 4.5″ midrange plus an additional 1″ tweeter—max power handling is spec’d at 300 watts.

Output from the BP9060’s 10″ active side-firing subwoofer driver is augmented by dual 10″ passive radiators. These towers have a slender profile; excluding the aluminum base, they measure 43.75″ (H) x 6″ (W) x 13″ (D). Each speaker weighs 50 pounds, with the sub adding some noticeable heft relative to the cabinet size.

The rear speakers in this rig are BP9040 towers. These have slightly more modest specifications when compared to the BP9060s, primarily because they use an 8″ active subwoofer and 8″ passive radiators, instead of 10″. Indeed, aside from cabinet height, and the size of the subwoofer, everything else about the BP9040 is pretty much identical to the BP9060.

In terms of the midrange and tweeters, impedance, power handling, and system sensitivity, BP9040s and BP9060s are the same. Definitive Technology specifies the frequency response of the BP9040s at 22 Hz to 40 kHz. These towers are slightly shorter than the BP9060s, measuring 38.25″ (H) x 6″ (W) x 13″ (D)—excluding the aluminum base and weigh 36 pounds. Note that width and depth are the same, this is to maintain A90 module compatibility between the two tower models.

Notably, both the BP9060 and BP9040 towers have removable aluminum tops and are pre-wired to accommodate the A90 Dolby Atmos-enabled modules in a seamless manner. Advantage of this approach is aesthetic; you don’t have to run a speaker cable off the back of the speaker, instead the module becomes a part of the tower.

Definitive Technology BP9000 Syspem with A90 Dolby Atmos-enabled modules
A90 Atmos-enabled modules attach to the tops of the BP9060 towers

The towers’ subs each have a built-in level adjustment that’s designed to maintain tonality while allowing the user to customize bass response. Thanks to this functionality, hobbyists with measurement gear can make initial adjustments prior to running room correction.

Next up is the CS9040 center channel. This particular model is neither bipolar nor active, but it’s designed to complement the other speakers in this line in terms of looks and performance. It has two bigger brothers (the CS9060 and CS9080) that do offer built-in active subs—like the towers do—but they cost more. This model offers a horizontal driver array consisting of dual 4.5″ mid/bass drivers flanking a 1″ aluminum-dome tweeter plus an 8″ passive radiator.

Definitive Technology specifies the frequency response of the CS9040 at 50 Hz to 40 kHz. This speaker can handle up to 200 watts of peak power, has a rated sensitivity of 89 dB/W/m, weighs 20 pounds, and measures 5.95″ (H) x 20.75″ (W) x 12″ (D).

A pair of Definitive Technology SR9040 speakers took care of side-surround duty in this system. They are a passive bipolar design that’s meant to be hung on a wall using a keyhole slot. Each SR9040 measures 9.5″ (H) x 7.8125″ (W) x 5.375″ (D).

SR9040 specifications cite a “total frequency response” of 50 Hz to 40 kHz, with a sensitivity of 92 dB/W/m. This 8-ohm speaker relies on two 3.5″ mid/bass drivers as well as two 1″ aluminum dome tweeters to generate sound with specifications indicating it’s able to handle up to 150 watts of peak power.

Finally, there’s the four A90 Atmos-enabled (and DTS:X compatible) modules. According to Definitive Technology, the 8-ohm A90 has a frequency response of 86 Hz to 40 kHz and 89.5 dB/Wm sensitivity. Each module weighs 6 pounds and measures 3.75″ (H) x 6″ (H) X 13″ (D)—exactly as wide and deep as the BP9040 and BP9060 towers.

Each A90 module depends on a single 4.5″ mid/bass driver and a single 1″ aluminum dome tweeter, both placed on an up-facing baffle that’s sloped at a Dolby-specified angle. Additionally, foam is used to dampen stray sound that would otherwise leak, resulting in a tight dispersion pattern that bounces sound off the ceiling.

In terms of what sort of room you need to get a good effect from the A90s, Definitive Technology says the following: “Your ceiling should be flat. Your ceiling material should be acoustically reflective (examples include drywall, plaster, hardwood or other rigid, non-sound absorbing material). Ideal ceiling height is between 7.5 and 12 feet, maximum recommended height is 14 feet.” So there you go!

Setup and Performance

Unpacking and assembly was easy and well thought-out. I liked the easy-to-attach aluminum base that included feet with blue felt, which is a nod to the company’s signature color.

Attaching the base and feet to a BP9060 tower

I’m fortunate to have a space dedicated to home theater that is amenable to using the reflected-sound Atmos-enabled approach for 3D immersive audio. It’s a rectangular shoebox, with a 9-foot ceiling. It’s 11 feet wide and 18 feet deep with a staircase in the rear that adds some extra volume. As far as seating goes, there’s just one couch in the room to worry about.

With this rig, when on the couch, my head is 10 feet away from the 120-inch, 2.40:1 aspect ratio Stewart FilmScreen StudioTek 130 non-perforated screen. The left and right speakers are toed-in and positioned about 18″ forward from the screen, plus fairly close to the side walls (with a few inches clearance for the subs). Overall, the geometry works out well for the Atmos-enabled modules.

The SR9040s went up on my side walls at about ear height, and the BP9040s went seven feet behind the couch, spaced about six feet apart. The CS9040 center channel sat right under the screen, perfectly centered.

Thanks to fortuitous coincidence, the review for these speakers coincided with a hands-on review of the StormAudio I.ISP integrated 3D immersive sound processor. This impressive device can feed 200 watts per channel into 12 channels—concurrently—making it a great match for the 11-channel Definitive Technology speaker system. What’s more, the I.ISP features Dirac Live room correction for all channels, which provides the best room correction and EQ around, plus it delivers useful information regarding the in-room performance of the system. Above all, it makes everything sound quite excellent!

A quick note on amplification: Yes, I used a system that can drive these speakers to their limits. When pushed in the same way, most AVRs will run out of steam before maxing out these speakers. Moreover, bass is what uses up most of the power in a such a system.

When you push an 11-channel speaker system hard, instead of getting the 2-channel rated wattage you see in marketing specs, get something much less when all channels are driven. However, with the built-in subwoofers of Definitive Technology’s BP9000 series speakers, you can spare your AVR at least part of the task of pumping all the air needed to get those subwoofer tones rumbling by offloading it to the built-in amps in the speakers.

In terms of real-world performance, these speakers are commendably good. As is often the case with in-room measurements of speakers and subs, bass extension is not quite up to what the specs promise. Post Dirac, I measured the BP9060’s deep bass extension at about 26 Hz (+/-3 dB) with a -10 dB point of about 22 or 23 Hz. Also, disabling EQ yielded similar results.

The BP9040s bass extension had an approximate +/-3 dB point of 30 Hz, and I pegged -10 dB at about 27 Hz. Again, this is in-room and post-Dirac, but pre-Dirac bass extension numbers are effectively the same. And truth be told, these are great bass extension numbers for both the BP9040 and BP9060. Furthermore, they are consistent with what you’d expect from standalone subs of a similar size and using the same sort of drivers. And any way you look at it, bass performance is objectively great for slender tower speakers of this size and cost.

Encouragingly, the CS9040 center met its published specs. In-room bass response that made it all the way down to 50 Hz at +/-3 dB, as promised.

The SR9040 bipolar satellites did fairly well, too. While the specified bass response of 50 Hz was at -15dB, I found +/-3dB was somewhere around 60 or 65 Hz—plenty deep for satellites when using a 100 Hz crossover like I did.

Meanwhile, the A90 Atmos-enabled modules have enough bass extension to serve their stated purpose, namely they reach down to 100 Hz or so before the bass response drops. I used a 120 Hz crossover and as far as I am concerned, as long as these reflected-sound elevation modules pass Dolby certification, that’s all she wrote on the topic.

It’s worth noting that you can use the subwoofers in the BP9060 and BP9040 tower speakers in a more traditional manner, by feeding them a mono line-level signal from a processor that’s employing bass management. But my take is if you are going to do that, you are probably better off just buying a sub or two to add to the system.

If there’s a compromise to be made with this system, it amounts to a physical limitation in peak output. After all, we’re talking about a speaker that relies on 4.5″ drivers, which can only move so much air. However, the upshot is those smaller drivers are fast and accurate.


At first, I ran the system full-range in a 7.0.4 configuration, which I found to be fully immersive, with deep bass impact and the capacity to render audio possessing fidelity typically associated with expensive speakers that are designed for two-channel music reproduction.

If you leave standalone subwoofers out of the equation, this system compares quite favorably to others I have reviewed, thanks to the extension of the built-in subs in the towers. Watching movies, the sound was nimble and well balanced, with plenty of impact. Overall, I’d argue that the home theater performance of the rig exceeds what I expect to hear from a similarly-priced system featuring all passive speakers.

However, the reality of this hands-on is that I already have multiple large, capable subs in the room. Consequently, by adding those to the mix, the Definitive Technology system operating in a 7.1.4-channel configuration can get down to 16 Hz at very high output levels.

Using the subs in conjunction with this system adds a tactile element to movie watching that relying on the BP9040 and BP9060 towers alone could not replicate. The end result sounded sublime by any standard, this is a configuration in which this system shines. I’m not saying that the 7.0.4 approach was not great, but just try watching Tron: Legacy with and without subs that get you down to 16 Hz; the difference is readily apparent.

A crucial part of this system’s overall great performance is the effectiveness of the A90 Atmos-enabled elevation modules. I’m happy to report that these modules proved highly effective at making sure the heights channels sounded like they were coming from above. Notably, I did not detect any sound leakage coming from the modules—Definitive Technology’s approach to keeping dispersion controlled appears to be effective.

In “old standby” Atmos demo movies like Gravity and Mad Max: Fury Road, the sense of 3D immersive audio envelopment was convincing. Additionally, dedicated Dolby Atmos demo clips made it abundantly clear that discrete overhead sounds were being rendered faithfully.

Of course it helps that I’ve set up many reflected-sound Atmos systems over the past few years, and learned how my room interacts with them along the way. And as I mentioned, I have a room that’s amenable to the reflected-sound approach in the first place. Nevertheless, the point here is that these modules work as they should.

While it’s axiomatic that installing physical speakers overhead is likely to produce the best results for 3D immersive height effects, the Atmos-enabled approach remains viable and effective when properly executed.

Recently, I used this system to watch the latest movies in UHD with Atmos soundtracks. From Wonder Woman to Spider-Man, and Baby Driver to Transformers: The Last Knight, each flick’s Atmos soundtrack rendered in a seamless manner, with clearly defined objects tracking through 3D space, ambience and effects that expanded beyond the room’s confines, and a soundfield that accurately reflected what was on screen.

Also notable was the clarity of the vocals coming from the CS9040 center speaker. In all, the system lives up to the promise of the company name by offering such high-definition audio performance. You won’t miss any deals found in the mix when using these Definitive Technology speakers.

Before wrapping up, I will confess to a degree of ambivalence regarding the bipolar design of the tower speakers, at least when used in a home theater application. But, it’s fair to say that I never found it to be a minus.


With its BP9040 and BP9060 towers, Definitive Technology gives you bass extension, sonic accuracy, and exceptional imaging in a sleek tower. Unless you have a large space and typically watch movies at very high volume levels, these speakers have more than enough headroom. And of course, Definitive does have step-up models for applications where more output is required. But trust me, for most music and movie lovers, these speakers have what it takes to serve as the foundation of a system.

Taken together, this 7.0.4 system from Definitive Technology delivers a complete immersive home theater experience. It’s a great 3D immersive audio surround-sound outfit that’s only made better if you add ultra deep-digging subwoofers to the mix. Indeed, in consideration of its capabilities, good looks, and because I did not once experience a break in suspension of disbelief when watching great movies with this system, I’ve decided it deserves an AVS Forum Top Choice 2017 award.


Processing and Amplification

StormAudio I.ISP 3D.16.12 integrated AV processor


Sony VPL-VW365ES 4K projector
Stewart Filmscreen 120″ (horizontal) 2.40:1 StudioTek 130 non-perforated


Roku Ultra
Oppo UDP-203 Ultra HD Blu-ray player


Blue Jeans Cable