User manual JBL SYN1

[. . . ] JBL Synthesis Four speaker systems feature the following: ® ® THX ULTRA2 -LICENSED HOME AUDIO SYSTEM: When used with a THX TM controller and amplifiers, your speaker system will deliver a state-of-the-art THX home theater experience to your living room. You will hear in your home exactly what the director and sound engineer heard in the recording studio. The system will reproduce the audio flawlessly and without distortion. ® FLUSH-MOUNT APPEARANCE: The S4Ai, S4VC and S4HC are designed to fit flush to your wall surface. Designers and interior decorators will be pleased by their hidden appearance and stunning performance. PURE-TITANIUM, HIGH-FREQUENCY TRANSDUCER DOME: The pure-titanium diaphragms with neodymium magnet structures are ultralight to accurately reproduce lightning-fast sounds ­ such as cymbal crashes ­ yet extremely rigid to eliminate distortion and ear fatigue. ELLIPTICAL OBLATE SPHEROIDAL (EOS) WAVEGUIDE: First developed for our JBL Professional LSR studio TM monitors, this unique structure enables Synthesis Four Series speakers to evenly disperse high frequencies, creating precise imaging over a wide listening area. PURE-TITANIUM, INVERTED-DOME, MIDRANGE TRANSDUCERS (S4VC, S4HC): The midrange drivers seamlessly complement the titanium-dome tweeter and offer nearly perfect pistonic motion, which eliminates the uncontrollable flexing found in conventional cones. The inverted dome is driven precisely at its center, which cancels resonances inherent in cone materials. [. . . ] Speakers and electronics terminals have corresponding (+) and (­) terminals. Most manufacturers of speakers and electronics, including JBL, use red to denote the (+) terminal and black for the (­) terminal, although some electronics manufacturers have adopted the new color-coding standard promulgated by the Consumer Electronics Association. In that case, the positive terminal will be colored to correspond to the channel position, while the negative terminal will be black. It is important to connect all speakers identically: (+) on the speaker to (+) on the amplifier and (­) on the speaker to (­) on the amplifier. Wiring "out of phase" results in thin sound, weak bass and poor imaging. With the advent of multichannel surround sound systems, connecting all of the speakers in your system with the correct polarity remains equally important to preserve the proper ambience and directionality of the program material. Now find a visual difference between the two conductors of each molded pair of speaker wires. Differentiating marks can be a different color wire (copper or silver); a strand of yarn in one conductor; thin, raised ribs on one part of the outer insulation; or a printed marking on one part of the outer insulation. It doesn't matter which of the two strands go to the (+) and (­) on the speakers and amplifiers, as long as all speakers are connected identically. Push down on the binding post, insert the wire into the hole, and release. 13 FINE-TUNING YOUR AUDIO SYSTEM ACOUSTICAL PROBLEMS IN LISTENING ROOMS A home THX audio system, such as the Synthesis Four system, addresses many of the problems common to high-quality reproduction of music or soundtracks in a home environment. For example, the dispersion pattern of the front LCR speakers minimizes the effects of floor and ceiling reflections. Commercially built diffusers are available, but large bookcases and irregularly shaped furniture will also serve the same purpose. They reflect sounds in a highly random way that effectively "scatters" the sound in all directions. Place the diffuser where you would otherwise place the absorptive material (using the "mirror trick"), to break up the first early reflections and scatter them randomly throughout the room. Commercially available fiberglass, foam and diffusion panels may not be aesthetically acceptable in many installations, particularly when the home theater room serves multiple purposes. All of these materials can be covered with acoustically transparent cloth for design considerations. It is important that the cloth be acoustically transparent, however, or the effectiveness of the absorptive material will be greatly reduced. The simplest test for this is to hold a large sample of the cloth in front of a speaker playing pink noise. If you can move the cloth in front of the speaker without hearing a difference, the cloth is good for use in this application. Glass reflects mids and highs, but often lets bass pass through, almost as if the glass were not there. The result is a characteristically bright, rough sound that can be difficult to correct electronically. The best treatment is generally the heaviest insulated drapes that can be found. [. . . ] This will sometimes take the form of a custom-designed bass trap, which may be easily constructed. In other cases, careful analysis and parametric equalization may be appropriate. Optimize everything else that you can, then use EQ, if necessary, to "touch up" the room. Parametric equalization must be applied with care and a light touch to obtain optimal results. [. . . ]