User manual AEA STEREO MIC POSITIONER

[. . . ] With zero at the center, these markings designate the distance between the sliders, with special markings to indicate the 17-cm spacing unique to the ORTF stereo system. The sliders are marked around the circumference at 0°, ±30°, ±45°, and ±55°. These represent included angles of 60°, 90°, and 110° respectively between the microphones, and may be used to facilitate exact and repeatable positioning of any conventional stereo perspective. [. . . ] Next, the included angle between the axes of pickup may be adjusted by rotating the microphones on the sliders, using the markings as a reference. When creating a coincident stereo array with two axial-address microphones, a vertical offset is desirable so that they may be positioned with their capsules one directly above the other. To accomplish this, a riser may be installed on one of the sliders if there is insufficient thread depth in the microphones' stand adaptors to achieve the offset directly. To create the riser, use an Atlas AD-4B male coupler with an AD-5B chrome female coupler. If you prefer, you may order a female coupler in black finish to match the SMP (AEA part no. SMP-C). Vertical orientation is similarly easy to accomplish, and enables even very large side address microphones to be configured into coincident stereo arrays, such as XY, Mid/Side (M/S) or Blumlein (crossed figure-of-eights). Simply install one of the sliders on either end of the bar; as before, the female coupler may be used to mount the SMP on a stand or boom arm. The other two sliders should be set ata spacing which will allow the two microphones to be positioned head-to-head as closely together as is possible, but without actually touching each other. Once the microphones are mounted on the bar, simply rotate them in their mounts to achieve the appropriate angle between their axes of pickup. For added safety when the SMP is used vertically, we suggest that the lower microphone slider always be positioned such that the thumbscrew may be secured through one of the mounting holes. When using Coles 4038 ribbon microphones, one microphone slider should be located at the third hole in from one end of the bar, and the other slider at the second hole in from the opposite end. When used with AEA's 4038-SA custom mounting adaptors, this will position these mics so that they do not interfere with each other. If you regularly use a particular pair of microphones with the SMP, you might consider drilling your own special positioning holes (5/16"diameter) to provide an even more secure and repeatable mounting. Often it is necessary to fly the microphones above an audience to minimize the visual intrusion during live performances. To hang the SMP array horizontally, a single support line should be connected to the center hole of the bar; this will suspend the array. Monofilament guy lines maybe tied to the outer holes to prevent rotation or to breast the array if needed. The microphone sliders should be oriented so that the microphones hang downward from the bar. [. . . ] We sell and service the mics and stock replacement parts. CB Electronics In North America we also represent CB Electronics, a leading worldwide supplier of machine control equipment to the sound-for-picture industry. Their products specialize in professional control of and translation between bi-phase, 9-pin serial and time code machines. [. . . ]