Bruel & Kjaer 4003 Pair, Ampria MCMA-4,4-Channel Preamp 1980's - Black

Vintage Brüel & Kjær (B&K) 4003 Microphone Pair with Ampria MCMA-4, 4-Channel Preamp, Cables & Acoustic Pressure EQ Balls Rare, fully functional vintage Brüel & Kjær 4003 microphone system featuring two high-voltage omnidirectional condenser microphones, a specialized four-channel Ampria preamplifier, four 50-foot cables, and two acoustic pressure equalization balls. Brüel & Kjær 4003 Microphones The B&K 4003 is a highly regarded professional omnidirectional condenser microphone originally developed for demanding recording applications where exceptional accuracy, transparency, and extended frequency response are essential. These microphones utilize a specialized 130V powering system, providing excellent dynamic range, extremely low distortion, and outstanding transient reproduction. B&K microphones are renowned for their precision engineering and have long been valued in classical recording, orchestral sessions, acoustic music production, and critical recording applications. Microphone Serial Numbers: 1022760 1022745 The serial numbers are exceptionally close, separated by only 15 units, suggesting these microphones may have originally been supplied as a stereo pair. However, their original pairing status has not been verified. Ampria MCMA-4 Four-Channel Microphone Preamplifier Included is a vintage Ampria four-channel microphone preamplifier, a relatively uncommon piece of professional audio equipment. The Ampria provides four microphone preamplifier channels in a single chassis. Its specialized configuration makes it particularly interesting to collectors and engineers working with vintage professional condenser microphone systems. Two channels (Channels 3 and 4) have been specifically fitted to accommodate the B&K 4003 microphones’ specialized 130V powering requirements. Both B&K 4003 microphones have been connected to and successfully operated with the Ampria preamplifier, making this a particularly desirable combination for anyone seeking a working vintage high-voltage microphone system. The remaining two preamplifier channels provide additional functionality. Acoustic Pressure Equalization Balls Also included are two acoustic pressure equalization balls designed for use with the B&K 4003 microphones. These spherical attachments modify the microphones’ high-frequency response and directional characteristics, providing additional flexibility when recording acoustic instruments, ensembles, and stereo soundfields. Included in This Package 2 × Brüel & Kjær 4003 condenser microphones 1 × Ampria four-channel microphone preamplifier 4 × 50-foot microphone cables 2 × Acoustic pressure equalization balls Condition and Operation Both B&K 4003 microphones are functional and have been successfully operated using the included Ampria preamplifier. The preamplifier’s specially configured channels provide compatibility with the microphones’ unusual powering requirements, eliminating the need to independently source a compatible high-voltage microphone powering system. This is an uncommon opportunity to acquire two classic B&K 4003 microphones together with a functioning, compatible preamplifier and accessories. An excellent package for professional recording engineers, classical and acoustic recording specialists, vintage microphone enthusiasts, and collectors of rare professional audio equipment.