User manual JBL 4344 MKII

[. . . ] These speakers continue the longstanding tradition of precise studio monitor sound for which JBL is famous. You will enjoy the benefits of a 2" highfrequency compression driver, cast frame low-frequency transducers with vented pole pieces, and JBL's proprietary Symmetrical Field Geometry magnet design, as well as high definition dividing networks incorporating the highest quality electronic components available. Low-Frequency Transducer The 4344MkII features an all-new 15" (381mm) low-frequency transducer developed specifically for the 4344MkII. Derived from JBL's legacy of highly powerful yet efficient bass drivers, this woofer delivers full low-frequency performance with clarity and speed unprecedented among 15" drivers. The voice coil is 4" (102mm) in diameter and wound on edge from flat aluminum ribbon wire on a thermoset compositeTM form. [. . . ] The low-frequency section of the dividing network is mounted on a dedicated circuit board that separates both electrical and magnetic properties from that of the midrange and tweeter sections. Additionally, the 4344MkII's dividing network allows for passive, bi-wire, passive bi-amp, and full active bi-amp operation. For the full active bi-amp mode we recommend the use of a high-quality electronic crossover. Professional Series No. Model 4344MkII Serial Number: JBL Incorporated, Northridge, CA USA 6 ULTRA HIGH FREQUENCY LEVEL, dB ­ 2. 5 ­ 6. 5 0 +1. 5 ­ HIGH FREQUENCY LEVEL, dB ­ 2. 5 ­ 6. 5 0 +1. 5 ­ MID FREQUENCY LEVEL, dB ­ 2. 5 ­ 6. 5 0 +1. 5 ­ Level adjustments are provided to allow precision frequency response contouring. The midrange, high-frequency, and ultrahigh-frequency drivers may be fine-tuned for optimum sound in any listening room. Battery Replacement The battery should be replaced approximately every 2 years. This is accomplished as follows: · Unscrew the two screws that hold the battery access cover in place. It is located on the upper portion of the dividing network, on the rear of the speaker enclosure (Figure 1). · Install the battery by aligning the battery terminals with the mating terminals in the network housing. Align male to female, female to male terminals, then snap the connectors together, assuring a tight connection. Battery Replacement Record Date Installed: Figure 1 Battery Installation BI-AMP BATTERY NORMAL/ BI-WIRE JBL INCORPORATED 8500 Balboa Blvd. , Northridge, CA USA High Frequency Low Frequency No. 7 Figure 2 Placement Position Top View Placement Ideally the systems should be placed at least three feet from any walls. The height, at the bottom of the Lens assembly, should be at ear level. The two speakers should be equidistant from your primary listening position; the distance should be determined by the distance between the speakers. We recommend that the angle between the speakers, at the listening position, be between 45° to 60°. For example, if the speakers are 8' apart, your listening position should be 8'­12' from each speaker. To widen the area in which the best stereo image will be perceived, turn the speaker to face the primary listening position (Figure 2). It is normally recommended that the 4344MkII loudspeakers be positioned so that the ultrahigh-frequency transducers are towards the outside. In some listening environments, however, the imaging characteristics may be improved by positioning the ultrahigh-frequency transducers towards the inside. We suggest you experiment with the positioning of your loudspeakers to determine the ideal placement in your listening room. 3' 3' 10 ­ 15 3' 3' 10 ­ 15 Position Front View 3' Ear level when seated in listening position No. 8 3' Speaker Connections The 4344MkII loudspeakers can be connected by one of several methods. The binding posts on the rear panel of the 4344MkII will accept most types of audio cable and connectors, including banana plugs and bare wire (Figure 3). For each channel, connect the red (+) terminal on the 4344MkII to the red (+) terminal on your amplifier. For each channel, connect the black (­) terminal on the 4344MkII to the black (­) terminal on the amplifier. [. . . ] If touch-up is necessary or the finish appears to be drying out, the surface may be re-oiled with a commercially available oil-finishing preparation. Stains may be removed with an aerosol cleaner, following the cleaner's instructions. All wiring connections should be inspected and cleaned or remade periodically. The frequency of maintenance depends on the metals involved in the connections, atmospheric conditions, and other factors, but once per year is the minimum. [. . . ]