Neumann BCM 104 Broadcast-Micro Cond. cardioid

The BCM 104 condenser microphone is the first product in the new Broadcast Line, which is especially tailored to the demands of professional radio announcing. What sets the Broadcast Line apart is a completely independent, functionally optimized design derived from extensive 3D simulations.

The large-diaphragm condenser capsule used in the BCM 104 has a cardioid directional pattern with internally switchable proximity effect compensation. A second switch allows the sensitivity to be reduced by 14 dB. The microphone headgrille twists off easily for quick cleaning. Neumann offers optional, color-coded headgrilles so that, for reasons of hygiene, each announcer working at an announcing desk can use his or her individual headgrille. Directly in front of the capsule, mounted on a frame holder, is a piece of fine gauze that serves as a built-in popscreen. The BCM 104 has an elastic mount against structure-borne noise, that is compatible with standard broadcast- segment microphone arms.

The microphone headgrille houses the K 04 large- diaphragm capsule, which has a flat frequency response up to 3 kHz. Higher frequencies have an increased presence of 2 dB maximum. Since these microphone characteristics are obtained without the use of resonance effects, the microphone features excellent transient response and transmits all transient phenomena of music and speech without any coloration. A pop screen not only prevents the occurrence of plosive pop noises in vocal recordings, but also efficiently prevents unwanted particles, from respiratory moisture to food remnants, from settling on the diaphragm. The pop screen can be removed for cleaning without the use of tools. Instead of a transformer to couple the microphone output to the supply voltage, the BCM 104 has an electronic circuit which, like a transformer, provides for good common mode rejection. Interference induced in the balanced modulation line is thus suppressed. With a very low self- noise of 7 dB(A), and an overload capability extending to 138 dB SPL, the BCM 104 has a dynamic range of 131 dB (DIN/IEC 651).

The BCM 104 amplifier has a linear operation down to 20 Hz. An active filter efficiently suppresses signals below this frequency. In order to compensate for the proximity effect, a high- pass filter, electronically activated by a switch, is built into the microphone. This filter reduces frequencies below 100 Hz by 12 dB/octave. A 14-dB preattenuation switch is provided in order to adjust the sensitivity, if necessary, to transmission circuits designed for dynamic microphones. But this will increase the self noise by 14 dB. Both switches are located inside the microphone housing, since they will normally be operated only once, when the broadcasting facility is set up. The preferred mounting method is to suspend the BCM 104 from a standard studio boom arm. A thread adapter to fit different connector threads is included. In order to provide protection from structure- borne noise, both the capsule and the microphone in its mount are elastically suspended. The optional SG 5 swivel mount allows additional angling of the BCM 104 by +/-90 degrees.

Features:

• Cardioid microphone for broadcast & studio
• Large diaphragm condenser capsule with switchable proximity compensation
• Distinctive design
• Integrated pop screen
• Quick release head grille for easy cleaning
• Individual head grilles available for each user

Specifications:

• Acoustical operating principle: Pressure gradient transducer
• Directional pattern: Cardioid
• Frequency range: 20 Hz...20 kHz
• Sensitivity at 1 kHz into 1 kohm: 22 mV/Pa
• -14 dB attenuation: 4.4 mV/Pa
• Rated impedance: 50 ohms
• Rated load impedance: 1000 ohms
• Equivalent SPL CCIR 468-3: 18 dB
• Equivalent SPL DIN/IEC 651: 7 dB-A
• S/N ratio CCIR 468-3: 76 dB
• S/N ratio DIN/IEC 651: 87 dB
• Maximum SPL for THD 0.5%: 138 d
• Maximum SPL for THD 0.5% with preattenuation: 152 dB
• Maximum output voltage: 10 dBu
• Dyn. range of the mic. amplifier DIN/IEC 651: 131 dB
• Supply voltage: 48 V ± 4 V
• Current consumption: 3.2 mA
• Matching connector: XLR 3 F
• Weight: 500 g
• Diameter: 64 mm
• Length: 85 mm