JBL MTC-PC3 Panel Cover Pair for Control SeriesThe MTC-PC3 are simple-to-use protective panel covers for the input terminal panel of many models of Control Contractor and Control Series loudspeakers. On the MTC-PC3, the wire exits from the side of the cover.
The Panel Cover installs over the existing input cup, provides a watertight gland-fitting entrance to seal and protect this section of the loudspeaker against incursion of water. The cover comes only in black. The cover section is paintable, but the gland nut is not.
Model compatibility -- MTC-PC3 fits JBL's standard 1.7" x 1.7" (43 x 43 mm) input cup which includes the following models (as of 03/2016): Control 23-1, 25-1, 28-1, SB2210, 25AV, 29AV, 30, 31, 1, 5. CBT 70J-1, 70JE-1, 200LA-1, 100LA-1, 50LA-1. Plus older models Control 23, 23T, 25, 25T, 28, 28T-60.
Important: In order to seal correctly, the cable must be jacketed externally with a round (or near-round) cross-sectional shape and the outside diameter of the cable MUST be between 0.170" (4.3 mm) and 0.470" (11.9 mm). Side-by-side "zip" type cables are not acceptable.
Constant Voltage (70-Volt) Audio Systems
Audio distribution systems, especially those commonly used in department stores, warehouses, restaurants, etc., require that many loudspeakers be driven from a single audio amplifier over long runs of speaker wire. The "constant voltage" or "high impedance distribution" audio systems can be complex to understand at first, however, provides many advantages. Learn how to design your own 70-volt or 25-volt loudspeaker system.
JBL MTC-PC2_PC3 Manual