Yes. The speakers in a THX home cinema system (both Ultra2 and Select) are optimized for multi-channel sound (4 or 5.1 channels), so you get better imaging and clarity from the front speakers, and more envelopment from the surround speakers. Both of these benefits are ideal for music reproduction.

The difficulty exists because dialogue in a film competes with music and sound effects. In addition, all of the sounds are coming at the listener from many different directions. Clearly, the best way to hear clean dialogue is to reproduce it with as little coloration as possible. This means you need to hear flat frequency response all across the listening area and have controlled speaker/room interaction.

THX home cinema 5.1 systems include three front speakers (left, centre and right), two surround speakers and one or more subwoofers. Many systems also include one (6.1) or two (7.1) more surround back speakers. Each speaker has its own specifications and characteristics although a flat frequency response in the range each speaker is called to perform, is a prerequisite.

The final requirement for accurate multi-channel sound reproduction is accurate deep bass response. All THX subwoofers are designed to precisely match left, centre, and right (LCR) speakers through the electronic crossover in a home THX processor or receiver. THX subwoofers must have an accurate in-room response from 35Hz to 200Hz so that the crossover at 80Hz results in a smooth transition. Approved systems must be able to generate 102dB sound pressure level or louder without distortion in a listening room of 2000 cubic feet (roughly equivalent to a 20 square metre room).

Conventional two-channel speaker designs are constructed to present a good solid image over a 45 to 60 degree angle. If you spread the speakers too far apart, you get a hole in the centre image. Place them too close together, and the soundstage collapses into a fuzzy mono sound. In a multi-channel sound system, sound images are formed between left and centre and right and centre speakers. This means that speakers must be more precise in their imaging characteristics.

Front channel imaging is extremely important in producing accurate sound. For films, the sound has to match the picture perfectly. Home THX front channel speakers improve dialogue intelligibility and imaging in two ways. First, they provide wide horizontal dispersion. This allows for people sitting off-axis to hear full and flat frequency response. The second technique is to control the speakers' vertical dispersion. Audio engineers have found that the ceiling and floor reflections deteriorate a speaker's ability to image. In addition, the coloration from these vertical reflections cloud intelligibility.

Few enthusiasts realize that the centre speaker handles almost 40% of the dialogue in a typical surround presentation! Our ‘Free Air’ spherical rotating tweeters and THX certified dispersion characteristics ensures you'll never miss a word of dialogue.

THX recommends that the surround speakers are dipolar, which are designed to provide a "movie without walls" experience. A dipolar speaker does this by painting the walls and the ceiling with sound. It sends very little sound towards the listener. The sound reflecting off the room’s walls and ceiling provides an enveloping soundfield, immersing the listener in the movie experience.

The total energy radiated by a speaker in all directions is called its "Power Response". The THX dipolar surround speaker is required to have a flat power response. This means that the total energy radiated by the speaker (in front, above, below, behind, and to the sides) must together average a flat frequency response. With the total speaker energy being flat, a listener anywhere within the surround speaker's firing area will hear flat frequency response.

In a cinema, the surround speakers and the front speakers are different because they do different jobs. The front speakers deliver clear dialogue and localized sound that matches the picture. The surround speakers create diffuse and enveloping surround ambiences with occasional effects like pans or "fly-overs." If you build a 5.1 channel home cinema system using conventional loudspeakers, you’ll need a minimum of five matched speakers plus a subwoofer for accurate sound reproduction. By contrast, THX home cinema speakers have multi-channel sound capabilities built in. THX LCR speakers and THX dipole surround designs psycho-acoustically match the best surround sound performance of a cinema or mixing stage. The THX subwoofer keeps the size of all of the speakers small while allowing for peak dynamic range and bass performance.

THX recommends the use of main L/R front speakers that handle bass frequencies down to 80Hz, with one or more subwoofers for frequencies below. When using smaller loudspeakers we can cut off the bass at 120Hz instead of the optimum 80Hz crossover point. The associated subwoofer crossover frequency must also be adjusted to handle frequencies up to 120Hz. And we make that easy because all our THX Select certified subwoofers faithfully reproduce the bass up to 200Hz! Crystal has you covered!