【 Weak current College 】 stage sound reinforcement project---Power By 【 China power house network 】

Speaker layout: the entire sound reinforcement system, loudspeaker (speaker) of the most important. Layout of have a direct impact on the entire sound reinforcement systems. 1: layout principles: 1) to enable the Hall sound field with uniform. 2) audio-visual direction. 3) favorable overcome transfusion, improving acoustic gain. 4) line of simple, easy to repair. 5) speaker sound than natural sound delay 5-30ms (MS). 6) speaker cover corner to include all of the Auditorium. 2: centralized layout: speakers near natural sound sources, generally on a desk top or height at stage II side. In the mouth a higher place in the stage II side can be combined with auxiliary sound columns, so that the sound image down, ensure the audiovisual. 3: half-centralized layout: in large or long Hall, speakers often used half a centralized layout, each speaker services. But be aware: in the hands of digitally, and between adjacent group speaker distance preferably 12 meters and a maximum of no more than 15 metres, to ensure that the back seat of the audience did not hear two voices. Near the front of a group of speakers power can be smaller, and its range for sound should be smaller. 4: distributed arrangement: when the Hall roof is low, or too long reverberation time, often dispersed. You can increase the direct-to-noise ratio. Speaker maximum direct sound pressure level calculated: LSP = LH + 201g1/r + 101Gwe which LH; the speakers 1W, 1 m, axial sensitivity level. R: the speakers to the audience point distance. WE: fed to speakers of electric power. Auditorium maximum sound pressure level: (strict formula) may be approximated for LPt = Lr Lr which LSP + is a constant, and total room sound absorbing capacity, the reverberation time, generally desirable 3-12dB (estimated value). Divider: 1.LC divider (passive frequency divider): 1) power frequency, restricted (inductance coil resistance to consume energy). 2) produce phase shift (coil and capacitor are perceptual component). 3) low cost, easy to operate. 2. electronic dividers (active frequency divider): 1) power voltage frequency, without restriction. 2) no phase shift. 3) to compensate for speaker balance between high and low range. 4) high costs, but also to increase the number of power amplifiers. 5) when using F + D, on the high and low unit respectively with delay, ensures that in-phase output and voice modification.