Surround Sound Speaker Systems
- Written by Ross Jones
- Published on 07 March 2011
- Crystal Acoustics TX-3D12 5.1 Home Theater Speaker System
- Page 2: Design and Setup of the Crystal Acoustics TX-3D12 5.1 Home Theater Speaker System
- Page 3: The Crystal Acoustics TX-3D12 5.1 Home Theater Speaker System In Use
- Page 4: The Crystal Acoustics TX-3D12 5.1 Home Theater Speaker System On the Bench
- Page 5: Conclusions About the Crystal Acoustics TX-3D12 5.1 Home Theater Speaker System
- All Pages
It was five years ago that I first heard Crystal Acoustics speakers. Crystal is a British-based OEM speaker manufacturer that started making THX certified speakers under its own name. Because Crystal sells direct through the Internet without the costs of a distribution network, it offers very low prices for its products. I was quite impressed by the price/value proposition of its TX-3D12 THX Select certified surround system.
- TX-T3SE Floor-Standing (Tower) Speaker
- Design: 3-½ way, Dual-ported
- THX Ultra2 Certified
- Drivers: One 1" Silk Dome Tweeter, Three 7" Woofers
- MFR: 33 Hz - 22 kHz
- Dimensions: 42.2" H x 8.3" W x 13.4" D
- Weight: 55 Pounds/each
- TX-CT Center Channel Speaker
- Design: 2-way, Dual-ported
- THX Select Certified
- Drivers: One 1" Silk Dome Tweeter, One 7" Mid/Bass
- MFR: 45 Hz - 22 kHz
- Dimensions: 8.5" H x 21.7" W x 6.4" D
- Weight: 15.5 Pounds
- THX-D Surround Speaker
- Design: 2-way, Ported, Dipole
- THX Select Certified
- Drivers: Two 1" Silk Dome Tweeters, One 7" Mid/Bass
- MFR: 45 Hz - 22 kHz
- Dimensions: 12.2" H x 12.2" W x 5.8" D
- Weight: 15.5 Pounds/each
- THX-12SUB Subwoofer
- Design: Powered Subwoofer, Dual Ported
- Driver: One 12"
- THX Select Certified
- Amplifier: 200 Watts RMS, 400 Watts Peak
- MFR: 20 Hz - 350 Hz
- Dimensions: 18.5" H x 13.8" W x 18.5" D
- Weight: 64 Pounds
- System Price: $1,999 USA
- Crystal Acoustics
So when I recently received a press release announcing Crystal Acoustics' latest system, the TX-3D12, which is anchored by the new THX Ultra2 certified TX-T3SE main speakers, I was excited to get my hands on a review sample. When I found out that the system is being offered at $1,999, my excitement turned to amazement. How could anyone possibly offer a 5.1 system featuring THX Ultra2 mains, plus a center-channel speaker, dipole surrounds and subwoofer that are all THX Select certified, for under $2,000? I was determined to find out.
Design and Setup
The TX-T3SE main speakers are similar in appearance to its predecessor, the THX-T3. Both speakers feature an externally mounted swiveling one-inch silk dome tweeter, and three seven-inch yellow "Crystal fibre" woven fiberglass woofers with bullet-cone phase plugs and two dimpled ports. The most obvious visual difference between the TX-T3SE and the former model is a deeper cabinet, making for increased interior volume. The TX-T3SE also has a more robust solid feel than the prior model, likely the result of additional interior bracing. The 3 ½-way TX-T3SE also has a redesigned crossover system, intended to achieve smoother frequency response between the woofers and mid-range drivers.
The larger cabinet and improved crossovers allow the TX-T3SE to serve as a full-range speaker, used without a subwoofer. Crystal Acoustics' white paper claims that the new design allows the TX-T3SE to produce 9 dB more power at 35 Hz, and 6 decibels more power at 40 Hz than its prior model, well below the operating frequencies of most floor-standing speakers. THX Ultra2 certification means that the TX-T3SE's are capable of very high output, along with excellent horizontal off-axis response.
As expected from a THX Ultra2 certified speaker, the TX-T3SE's are highly sensitive speakers, rated at 92 dB (2.83V/1 meter). A similar speaker rated at 89 dB sensitivity would require twice as much wattage to get that extra three decibels of output. In fact, you can tell that the company CEO is also head of Research and Development, because the rear panel of the TX-T3SE lists not just the speaker's nominal impedance but also minimum impedance, the rated frequency response and sensitivity.
The THX-D dipole surround speakers are similar to the prior models, in that they use the same front-firing seven inch woofer as the TX-T3SE's, with two side-firing one-inch silk dome tweeters wired out of phase. I've been using the prior version of the THX-D dipoles as my side-surround speakers in my main system. The newer dipoles are physically slightly smaller than the prior model, yet have better low-end frequency response than its predecessors (45 Hz versus 65Hz).
Likewise, the THX-CT center uses the same seven inch woofer with a top-mounted tweeter is the preferred vertical orientation, flanked by two small ports. The THX-C is nominally rated at 4 ohms, unlike the mains and surround speakers that are rated at nominal 8 ohms. The speakers came trimmed in a gloss black ash finish over MDF that gave them a stylish but not ostentatious appearance, certainly more than expected at this price range.
The THX-12SUB features a 12" front-mounted woofer powered by a 200 watt (rms) amplifier. The back panel of the sub provides a single line-level input, a phase reverse switch and a two-position crossover switch which can be set to "THX" (meaning 80 Hz), or variable, in which case the crossover is set by the receiver or processor rather than the sub. The rear of the sub also has two large ports for low frequency extension. Crystal's spec sheet lists the THX-12SUB rated frequency response flat to 35 Hz, with usable extension down to 20 Hz.
My usual experience with THX certified speakers is to expect trade-offs between home theater and music listening. THX speakers are designed to maximize wide horizontal off-axis response, and limited vertical off-axis response for an immersive movie environment. As a result, most THX speakers I've heard sound fine with film soundtracks, but suffer to varying degrees with less-than-stellar imaging on music material.
I started by dialing up Tom Petty and the Heartbreakers' amazing new Blu-ray audio recording of Damn The Torpedoes. The original CD was a well-produced album, but the Blu-ray audio version is so fine it could be the subject of its own article. I was expecting the Crystal Acoustics' to reproduce the wonderful tones of the Heartbreakers, but not much in the way of imaging. So I was nicely surprised with the TX-T3SE's ability to separate instruments in the 5.1 soundstage. Stan Lynch's drumming, particularly on well-known tracks such as Refugee and Don't Do Me Like That, was larger than life on the Crystals'.
The Crystal Acoustics' spent part of football season in my listening room, so weekends provided a heavy dose of NFL action (via HD Comcast cable, 5.1 Dolby Digital). Watching games through the Crystal Acoustics were a real treat, especially with the THX-D dipole surround speakers providing realistic crowd ambience. It was almost like being at the game, except without the long lines at the bathroom.
Pixar does nothing other than make consistently superb films with eye-dropping visuals, wonderful characters, an uncanny ability to make me cry at the end of the movie, and of course fantastic sound. Toy Story 3 is no exception, with a soundtrack that includes everything from a fashion-conscious Ken to garbage trucks and landfill furnaces. The Crystal Acoustics really shined on the DTS-HD Master Audio, providing an enveloping soundstage and dynamic contrast. The THX-12SUB provided a solid foundation, with robust power in the mid and low bass frequencies. I did not get a sense of much infrasonic bass energy, which is to be expected given the rated frequency response of the sub, but there was a ton of room-filling pressure when it counted.
The TX-T3SE's are sensitive speakers, meaning they don't need a lot of power, but I found myself turning them up because they seemed to like it. No matter how hard I pushed them, the Crystal Acoustics' never sounded "loud" in the compressed, harsh sense of the word. They had the clear, powerful demeanor like you find in top-notch movie houses. In fact, the only issue I could take with the Crystal Acoustics' performance was an occasional volume mismatch between the THX-CT and the rest of the system. The THX-CT center-channel speaker is much smaller compared to TX-T3SE main speakers, an intentional decision made by Crystal to maintain a small visual footprint (especially when mated with flat screen displays). I found that as the volume increased, the center channel speaker occasionally would drop a bit behind the rest of the system.
On the Bench
All bench tests were performed with the speakers in the middle of the room, to avoid interaction with corners and walls. Except as noted below, all measurements were taken from one foot at a height equal to the center of the speaker being tested.
The TX-T3SE's tweeter had very low distortion at 1 kilohertz.
Distortion at 10 kHz was 0.33 THD+N.
The TX-T3SE is designed to be used as a full-range speaker, without a subwoofer. Distortion at 50 Hz is a very low 1.82%. Some subwoofers that have trouble producing 50Hz at such low distortion.
At 35 Hz, below the lowest note of a bass guitar, the TX-T3SE was still producing 84 decibels without clipping.
The back of the TX-T3SE speakers list the minimum impedance as 3.2 ohms, consistent with my measurements showing the impedance dipping to 3 ohms between 1500-2500 Hz. Phase angle above the LF crossover is within 50 degrees.
Crystal Acoustics lists the THX-12SUB as flat down to 35 Hz, which seems conservative since my tests showed the sub producing very low distortion (3.23%) at the even lower third-octave frequency of 31.5 Hz.
I was so impressed by the low frequency output that I cranked up the 31.5 Hz sine wave, and even at a room-shaking 108 decibels, distortion was still an impressively low 3.87%. The THX-12SUB could have taken more, but it had already made its point.
The total harmonic frequency plus noise vs. frequency graph shows that the THX-12SUB dips below 10% distortion at 27 Hz, and after a spike at 40 Hz (likely the port tuning frequency) distortion drops off rapidly. This is really good performance for a sub that sells for only $649. Even more amazing, the black ash version of the THX-12SUB was at this writing offered via web special at the Crystal Audio website for only $399.
Crystal Acoustics has hit another home run in the price-performance category. Two thousand dollars buys a set of THX Ultra2 certified full-range speakers, a THX Select certified subwoofer that plays really loud down to 31.5 Hz, THX Select certified dipole and center-channel speakers that fill a room with immersive sound. This review didn't meet the deadline for SECRETS 2010 Best Of awards, but when nominations are due for the 2011 Best of awards, the Crystal Acoustics' TX-T3SE system has my vote.