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MULTI-PURPOSE SOUND SYSTEM Section 16780 15-1207 5. Integrity of soldered connections. 6. Absence of solder splatter, solder bridges, debris of any kind, tools, etc. 7. Proper routing and dressing or wire and cable. 8. 'Wire -checking" of all circuitry, including polarity and continuity, with reference to cable designations on run sheets, field and shop drawings. 9. Mechanical integrity of all support and positioning provisions, i.e., loudspeaker and cluster assemblies, etc. 10. Proper polarity and connection of loudspeaker assemblies. 11. Measurement and documentation of all loudspeaker circuit Impedances. C. Determine the proper sequence of energizing systems to minimize the risk of component damage. D. Make all preliminary adjustments and document the setting of all controls, parameters of all corrective networks, voltages at key system interconnection points, gains and losses, as applicable. E. Provide permanent "wedge," type labels on all controls, as applies, to indicate correct settings after performance testing and adjustment procedures have been successfully completed. 3.9 INITIAL POST COMPLETION TESTS AND ADJUSTMENT PROCEDURES: A. Upon completion of the installation of all equipment, and when it is in full operating condition, the Contractor shall perform the following initial post completion tests and adjustments. B. Loudspeaker line impedance: Measure the impedance and the resistance of each loudspeaker line leaving the racks (with the line disconnected from its normal driving source). The absolute value of impedance shall be measured at 200 Hz and 2 kHz. With three (3) or four (4) way systems, measure at least one frequency within the band covered by each component. C. Hum and noise level: Measurement of the hum and noise level of the overall system shall be measured for each microphone input channel and line level input channel. During the test: 1. Gain controls shall be adjusted for optimum signal to noise ratio and such that full amplifier output would be achieved with -40 dBm input level at a microphone input and +12 dBm at a line level input. 2. Microphone and line level inputs shall be terminated with shielded resistors of 150 and 600 ohms, respectively, for these measurements. 3. Disconnect the loudspeaker lines and terminate the power amplifier outputs with power resistors. The value of the load resistors shall be equal to the nominal output impedance of the amplifier under test with 10% tolerance of the resistance. D. Freedom from parasitic oscillation and RFI pickup: With systems set up for each mode of operation specified in the functional requirements, the contractor shall check to 25