User manual ELECTRO-VOICE MH640C EDS

[. . . ] The HP66 horn features integral fiberglass-and-zinc construction for exceptional strength and performance. Beamwidthcontrol vanes in the horn throat correct all coverage anomalies in the 10- to 20-kHz octave. This horn and driver combination is securely mounted to the mid-bass horn by a heavy-duty steel bracket. The mid-bass system is composed of a DL10X-SH 24. 5-cm (10-in. ) reproducer mounted on a MH660 60 x 60 deg. [. . . ] Each module is rotated, then the horizontal and verof the mounting brackets contains a %-in. tical polars should be interchanged. diameter hole through which a shackle or chain Figure 2 illustrates the horizontal and vertical link could pass. Beamwidth is the angle at which in any direction. Electro-Voice strongly recommends that each MH660C be suspended inde- the horizontal and vertical polar responses have decreased in level by 6 dB when compendently using at least three of the four suspared to the on-axis frequency response. If the MH660C is suspended, it is recommended that the unit be inspected at least once a year. If any sign of weakness is detected, remedial action should be taken immediately. CAUTION: The MH660C speaker systems should be suspended overhead only In accordance with the procedures and Iimitatfons specified in the installation manual Included wlth the systems. CONNECTIONS Each frequency section can be individually connected via #10 screw terminals. All drivers are connected with the same polarity. A positive voltage applied to the positively marked terminal produces a positive acoustic pressure at the front of the system. Figure 3 represents the total directivity of the MH660C The directivity factor R, (Q) is the relative value, at a point, when compared to an ideal spherical response. With its superior directivity frequency section requires a 1, 600-Hz crosscontrol, the MH660C is a system that can be over and the typical constant-directivity-horn used in almost any situation. A 0. 6-msec signal sound pedigree of the MH660C is evident by delay provides the smoothest response in the the ease of installation and by the use of profes- crossover region. A low-frequency blocking capacitor with a 3-dB-down point of 800 Hz is sional-grade components throughout the line. SUSPENDING MH660C ENCLOSURES An Electro-Voice XEQ-3 electronic crossover/ Suspending any object is potentially dangerequalizer/time delay unit with EQW plug-in ous and should only be attempted by individumodule provides all of the necessary signal als who have a thorough knowledge of the processing. The XEQ-3 is a three-way electechniques and regulations of rigging objects tronic crossover with adjustable crossover freoverhead. Electro-Voice strongly recommends quencies utilizing Linkwitz-Riley 24-dB-per-octhat the MH66OC be suspended taking into tave filters and signal delay equalization to account a// current national, federal, state and achieve zero lobbing error. It is the responsibility of the installer to ensure the MH660C is safely inFREQUENCY RESPONSE stalled in accordance with all such regulations. The MH660C axial frequency response was If the MH660C is suspended, Electro-Voice measured in Electro-Voice' large anechoic s strong/y recommends that the system be inchamber at a distance of 3 meters (10 feet) with spected af least once a year. If any sign of a swept sine-wave input (see Figure 1). It has weakness or damage is detected, remedial been normalized for 1 watt/l meter into the midaction should be taken immediate/y. Minimal level adjustment and equalization have been used. [. . . ] This overview does anechoic chamber, with a test signal of onenot replace the installing the MHSeries manual, third-octave filtered pink noise at the frequenwhich includes additional information on suscies indicated. A full spherical measurement pending, configuring and equalizing the MH system, which is fully compatible with Electroseries. Voice' AcoustaCADD computer-aided des sign program, was used. Kevlar is a registered trademark of Dupont. [. . . ]