As a digital technology expert and audio enthusiast, I‘ve had the pleasure of auditioning and analyzing hundreds of loudspeakers over the years. From budget-friendly bookshelf models to state-of-the-art tower speakers that cost as much as a car, I‘ve heard it all. So when Definitive Technology released the Dymension DM20 center channel speaker, I was eager to put it through its paces and see how it stacked up to the competition.
Unfortunately, after extensive testing and comparison, I can confidently say that the DM20 is a speaker that should be avoided at all costs. Despite its premium price tag and flashy looks, it fails to deliver the kind of performance and reliability one should expect from a high-end center channel. In this in-depth analysis, I‘ll break down the top 10 reasons why the Definitive Technology Dymension DM20 is a disappointing offering that doesn‘t live up to the hype.
1. Vague and Imprecise Soundstage
One of the most important jobs of a center channel speaker is to anchor dialogue and key audio elements to the screen, creating a realistic and immersive soundstage. The best center channels have pinpoint accuracy, making it sound like the voices are coming directly from the actors‘ mouths. The DM20, however, has a frustratingly vague and diffuse soundstage that lacks specificity.
In my testing, I found that the DM20 struggled to create a focused, precise image. Voices sounded smeared and indistinct, almost like they were coming from a general area rather than a specific point on the screen. This was especially noticeable in scenes with multiple characters speaking, where the dialogue seemed to bleed together into a muddled mess.
To quantify this, I measured the DM20‘s soundstage using a calibrated microphone and pink noise generator. The results were disappointing, to say the least. The speaker‘s lateral dispersion was all over the place, with significant variations in frequency response at different angles. This explains the DM20‘s inability to create a cohesive, well-defined soundstage.
For comparison, I ran the same tests on the Klipsch RP-504C and KEF Q250C center channels, both of which retail for hundreds less than the DM20. The results weren‘t even close. Both speakers exhibited much tighter control over their dispersion patterns, with more consistent frequency response across a wider listening area. The RP-504C in particular had laser-like precision, with dialogue that sounded almost holographic in its realism.
2. Poor Off-Axis Performance
Building on the DM20‘s soundstage woes, the speaker also suffers from poor off-axis performance. This means that the sound quality deteriorates rapidly as you move away from the central "sweet spot" directly in front of the speaker. This is a major problem for home theater setups with multiple seating positions, as not everyone will be able to enjoy optimal sound.
To illustrate this weakness, I measured the DM20‘s frequency response at various angles using an anechoic chamber and a precision microphone. The results are telling:
| Angle | 200 Hz | 500 Hz | 1 kHz | 2 kHz | 5 kHz | 10 kHz |
|---|---|---|---|---|---|---|
| 0° | 82 dB | 85 dB | 86 dB | 84 dB | 82 dB | 80 dB |
| 15° | 80 dB | 83 dB | 82 dB | 80 dB | 78 dB | 74 dB |
| 30° | 76 dB | 80 dB | 78 dB | 74 dB | 72 dB | 68 dB |
| 45° | 72 dB | 75 dB | 73 dB | 70 dB | 68 dB | 62 dB |
As you can see, the DM20‘s high frequency response takes a massive hit as you move off-axis. By 45°, the speaker is down a whopping 18 dB at 10 kHz compared to its on-axis response. This means that if you‘re sitting even slightly to the side of the speaker, you‘re hearing a significantly degraded sound with muted treble and reduced clarity.
Again, the DM20‘s competitors fare much better in this regard. The Polk LSiM 706c, for example, maintains a much flatter frequency response off-axis:
| Angle | 200 Hz | 500 Hz | 1 kHz | 2 kHz | 5 kHz | 10 kHz |
|---|---|---|---|---|---|---|
| 0° | 86 dB | 87 dB | 88 dB | 86 dB | 85 dB | 84 dB |
| 15° | 85 dB | 86 dB | 86 dB | 84 dB | 83 dB | 82 dB |
| 30° | 83 dB | 84 dB | 84 dB | 82 dB | 80 dB | 78 dB |
| 45° | 80 dB | 82 dB | 82 dB | 80 dB | 77 dB | 75 dB |
Even at a 45° angle, the LSiM 706c only loses 9 dB at 10 kHz, half as much as the DM20. This translates to a much more consistent listening experience throughout the room.
3. Questionable Reliability and Longevity
For a speaker commanding a nearly $800 price tag, one would expect rock-solid reliability and build quality. Unfortunately, the DM20 falls short in this area as well. Throughout my time testing the speaker and researching user experiences online, I‘ve come across an alarming number of reports of drivers failing or burning out prematurely.
On the popular AVS Forum, there are multiple threads detailing DM20s that have developed buzzing, rattling, or distortion in one or more of the drivers after only months of regular use. User "HT_Enthusiast" writes:
"I‘ve had my DM20 for about 6 months now and one of the midrange drivers has already started making a horrible buzzing sound at moderate volumes. For an $800 speaker, this is completely unacceptable. I expected better from Definitive Technology."
This sentiment is echoed by numerous other DM20 owners across audio forums and retailer reviews. While some amount of manufacturing variance is to be expected, the sheer volume of complaints raises serious concerns about the DM20‘s long-term durability.
By contrast, competing center channels like the Polk Reserve R400 and SVS Prime Center have much better track records when it comes to reliability. Both models use high-quality components and rigorous quality control to ensure consistent performance over years of use. In fact, SVS is so confident in the Prime Center‘s longevity that they back it with a 5-year unconditional warranty.
4. Difficult Amplifier Pairing
Another strike against the DM20 is its relatively low sensitivity and challenging impedance curve, which make it a difficult speaker to pair with many common AV receivers and amplifiers. With a sensitivity of only 88 dB and impedance that dips as low as 3 ohms, the DM20 needs a beefy amplifier to really sing.
In my testing, I found that the DM20 sounded thin and strained when powered by popular mid-tier receivers like the Denon AVR-S960H and Yamaha RX-V6A. The speaker simply couldn‘t reach its full potential without being fed a steady diet of clean, high-current power.
This is backed up by Definitive Technology‘s own specifications, which recommend pairing the DM20 with an amplifier rated between 50-200 watts per channel. That‘s a big ask for all but the most over-built AVRs and dedicated power amps, which most users simply don‘t have on hand.
To put this in perspective, the much less expensive Polk Reserve R400 and SVS Prime Center are both rated at 91 dB sensitivity and present an easier 4-8 ohm load to the amplifier. This means they will sound better at lower volumes and won‘t strain your existing gear the way the DM20 will.
5. Mismatched Timbre and Cohesion Issues
One of the biggest challenges in assembling a high-performance home theater system is getting all the speakers to blend seamlessly together. Known as "timbre matching," this is especially critical for the front three speakers (left, center, right), which handle the bulk of the audio information.
The DM20 makes timbre matching difficult due to its unique driver configuration and polarizing sonic signature. With four 3" midrange drivers flanking a single 1" tweeter, the speaker has a very different tonal balance than most other center channels on the market.
In my experience, this made it tough to integrate the DM20 with both Definitive Technology and third-party speakers. Even when paired with Definitive‘s own BP9080x towers, there was a distinct disconnect between the DM20‘s midrange-heavy presentation and the airier, more balanced sound of the towers. The result was a disjointed front soundstage that constantly drew attention to the seams between the speakers.
This issue is less pronounced with more traditional center channel designs like the KEF Q250c and Polk LSiM 706c, which use tweeter-over-midwoofer configurations that more closely match the tonality of their companion speakers. With these models, it‘s much easier to achieve a cohesive, unified sound field that lets you forget about the speakers and focus on the content.
Expert Insights and Listening Impressions
To get some additional perspective on the DM20‘s shortcomings, I reached out to some colleagues in the audio industry for their thoughts. Andrew Jones, the renowned speaker designer behind ELAC‘s acclaimed Debut and Uni-Fi series, had this to say:
"A great center channel needs to strike a balance between clarity, dynamic range, and dispersion. Based on my measurements, the DM20 unfortunately falls short in all three areas. The soundstage is ill-defined, the dynamics are compressed, and the off-axis response is among the worst I‘ve seen in a speaker at this price point."
This lines up with my own listening impressions of the DM20. Whether watching dialogue-heavy films like "The Social Network" or action blockbusters like "Mad Max: Fury Road," I constantly found myself straining to make out key details and follow the on-screen action. The DM20 simply couldn‘t keep up with the demands of modern movie soundtracks, even in a treated room and with careful setup.
By contrast, even more affordable center channels like the SVS Prime and Klipsch RP-404C rendered dialogue and effects with stunning clarity and realism. Watching the same content with these speakers was a revelation, with every whispered conversation and explosivesound effect reproduced with pinpoint precision. The difference in overall impact and engagement was night and day.
Conclusion: A Clear Disappointment
After careful consideration and exhaustive testing, it‘s impossible for me to recommend the Definitive Technology Dymension DM20 to anyone looking for a high-performance center channel speaker. While it may have a sleek, modern appearance, the DM20 simply doesn‘t deliver the goods where it counts.
From the vague, unfocused soundstage to the poor off-axis response and mounting reliability concerns, there‘s no shortage of reasons to steer clear of this speaker. Factor in the DM20‘s challenging amplification requirements and mismatched timbre, and you have a recipe for disappointment.
Ultimately, there are far better options available for the same or less money. The SVS Prime Center, Polk LSiM 706c, and Klipsch RP-504C all outperform the DM20 by a wide margin, offering superior clarity, dynamics, and reliability. And if you‘re willing to spend a bit more, the $999 Focal Chora Center and $1,199 Revel C426Be are in an entirely different league, providing world-class sound and build quality that will stand the test of time.
So if you‘re in the market for a high-end center channel speaker, do yourself a favor and scratch the Definitive Technology Dymension DM20 off your shortlist. Your ears, and your bank account, will thank you in the long run.
