Surround Sound Speaker Systems

Crystal Acoustics TX-3D12 5.1 Home Theater Speaker System


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.