Sennheiser MKH 416 The MKH Story - Page 6

The MKH Story A new microphone line is born A new microphone line was designed at the beginning of the 1980s to feature identical technical data as far as the differences were not dictated by the specific directional characteristics. Importantly, the frequency response should be flat for all types. The microphones should be neutral, without adding or omitting sound details. The RF circuitry was completely redesigned, now utilising amplitude modulation (AM) instead of phase modulation. This was evident, as the capsule is comprised of two capacitors with opposite varying capacitances. The capsule was combined with a centre-tapped coil to form an RF bridge. The capsule capacitances functioned like a capacitive potentiometer with the diaphragm as the wiper. This circuit exhibited an extraordinary linearity. The cardioid MKH 40 The MKH 40, as the first microphone of the new symmetrical-capsule MKH line, was launched in 1985.This microphone actually incorporated all the essential specifications of the future microphones. The frequency response was virtually flat from 40 Hz to 20 kHz, and the directional characteristics were stable over a wide frequency range. The distortion was extremely low, and the equivalent noise level of 20 dB(CCIR) and 12 dB(A), respectively, set a new milestone. The high sensitivity of 25 mV/Pa provided an interference-free operation even with long cables and reduced the noise contribution of the microphone amplifier considerably. Switches for pre-attenuation and bass roll-off were also incorporated, with the bass roll-off switch compensating for the proximity effect. The positive response of the sound engineers was encouraging. This indicated that the technical efforts had not only improved the measured results, but also yielded audible improvements in normal recording situations. The omnidirectional MKH 20 The next microphone requested by many sound engineers was an omnidirectional one. This type of microphone was rediscovered at the onset of digital audio because it enabled the engineer to include more authentic room acoustics than other microphone types. The MKH 20 (launched in 1986) met these expectations as its low noise performance revealed even faint tonal structures. With omnidirectional microphones, usually a decision has to be made between versions optimised for free-field or diffuse-field applications. The MKH 20 is switchable to both characteristics and, in addition, is supplied complete with a removable pressure ring enabling fine-tuning of the treble balance. Page 6