Microtech Gefell GmbH at the IBC in Amsterdam from September 12-15, 2025

The the further developed modular microphone system "Generation 4"

The modular microphone system "Generation 4" is characterized by the following key data:

• newly developed ultra-small microphone amplifier,
• two connector systems (XLR is standard, Lemo is also available),
• 4 capsules with correspondingly different directional characteristics:
• M 40 (cardioid), M 41 (super cardioid), M 42 (omnidirectional) and M 43 (wide-cardioid)
• various mounts

The Gefell modular microphone tradition

There have always been modular microphone solutions in the history of the company, starting with the M 7 capsule on a tube amplifier. Then the SMS 70 series with tube and later transistor amplifiers. Generation 4 is based on the predecessor series SMS 2000.

The "Generation 4" amplifier is a further development with modern components that enable a compact design with a length of just 80 mm. The capsules are a further development of the existing Gefell capsules. This also ensures continuity in terms of the microphone sound.

The start of "Generation 4" includes the ultra-compact microphone preamplifier MV 400 with two alternative connectors, the microphone capsules M 40 (cardioid), M 41 (super cardioid), M 42 (omnidirectional) and M 43 (wide-cardioid) as well as options and accessories for professional use.

The advantage of the modular concept is a fast reaction to changing requirements and a more productive workflow. With Generation 4, Microtech Gefell evolves from their existing tradition of modular microphone systems into a new and ultra-compact dimension.

 The new developed compact multi-channel condenser microphon MKM 403

MKM 403 microphone system with 3 separate channels

• condenser microphone
• cardioid
• Generation 4 microfons
• PE diaphragm
• modular microphone system
• small diaphragm capsule

The special task included the development of specially designed, compact multi-channel condenser microphones as part of a renewal of the existing audio systems in Mecca and Medina, including the microphone technology.

A particular challenge was to develop a microphone that was able to realize the function of three of the microphones previously used on site in one microphone housing.

Building on years of experience with microphones for parliaments, conferences, concert halls and more, such as the KEM 975 with eight microphone capsules, which is used worldwide, MTG was able to develop a suitable solution.

The MKM 403 features three independent Generation 4 M 40 capsules for 3 microphone channels, each with an MV 400 X microphone preamplifier optimized for both front and side pickup.

In contrast to the KEM 975, only one microphone is in operation in the MKM 403, with two more serving as a reserve. In addition, a miniature loudspeaker is integrated, which plays a test tone that is imperceptible to the human ear, which the three built-in microphones pick up and transmit to the audio system. If one microphone path is disturbed, the system switches to the next.

Special climate and temperature requirements also had to be taken into account. For example, smooth operation had to be guaranteed in direct sunlight and at temperatures of over 50° C.

The design meets the customer’s express wishes. The microphones were to be gold-plated on the outside, including the stands.  The protective cages were to be black. After extensive surface preparation of the housing parts by MTG, the gold plating of the polished parts was realized in cooperation with a renowned regional partners. The Salzbrenner company supplemented the range with automatically height-adjustable stands with storable positions.

The Cardioid Plane Microphone with non-rotation-symmetrical polar pattern KEM 975

• Line array condenser microphone system
• Recording of extensive or moving sound sources
• Optical display for optimum recording area
• Latency-free analogue signal processing
• Transformer-balanced output, line level

Optional with delta capsule

• Frequency-constant directivity index

The cardioid plane microphone KEM 975 is a line array microphone system with a largely frequency-independent polar pattern, which in the horizontal plane has the features of a cardioid microphone and  in the vertical plane  the features of a directional microphone with an operating angle of approx. 30 degrees.

Thus, the polar pattern is adapted to the frequent case that the sound source to be captured is wide in space or moves around in it and, at the same time, sound coming from other directions is to be suppressed.

The sound to be rejected may consist of disturbing noises or reflections which come from the ceiling, table surfaces or floor areas.

Due to its directional characteristics, the KEM 975 can be used for recording sound sources that are very extensive in width and depth or moving sound sources.

Since the complete signal processing is analogue, there are no signal delays.