JBL CINEMA SOUND SET UP, Руководство пользователя

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D. New JBL Driver Developments
Our studies have indicated that, in passive systems, maximum power input to the screen
loudspeakers is essentially network limited. As a result of this, many cinema applications ordinarily will
not require the high power Vented Gap
performance designed into the JBL 2226
driver. A more recent model, the 2035, was subsequently designed with a 76 mm (3 in.) voice coil,
retaining the same sensitivity of the 2226. Resulting economies can thus be passed on to the user.
In biamplified systems for larger houses we strongly recommend that the 2226 transducers be
used, because of their higher peak power and transient capabilities.
Figure 13 shows the on-axis response of the dual low frequency 4638 system, which
incorporates two of the 2035 transducers.
On-axis response of dual 360 mm
(15
in.) 4636TH LF system.
E. Mechanical Details of JBL Screen Loudspeaker Systems
The main JBL loudspeakers recommended for behind-screen use are discussed in this
section. Since all of these systems are intended for field assembly, we will show them in exploded
views, along with a parts list and a wiring diagram for use with a high-level dividing network.
Figure 14 shows dimensional aspects on field assembled 4670D and systems, clearly
indicating their overall space requirements. The models 4671 B, and
4638TH are shown, respectively, in Figures 15 through 19.
Passive network hook-up details are shown in Figure 20. Wiring instructions for biamplification
will be discussed in a later section.