The dummy head has its place, even in the age of surround sound. It is highly recommended by some audio engineers for the rear channels.
The Neumann KU 100 dummy head is a binaural stereo microphone. It resembles the human head and has two microphone capsules built into the ears. When listening through high-quality headphones it gives the illusion of being right at the scene of the acoustic events.
When using the KU 100 dummy head, the binaural stereo experience moves the listener into the scene of the original performance, in contrast to other space-related recording techniques, where the acoustic event is moved to the listener.
The dummy head is also used in many industrial applications as a measuring device, for example in acoustic research. The KU 100 can be operated with typical 48 V phantom powering, or from an external power supply unit, or from the built-in battery.
At the bottom of the unit is a switch for the different power supply modes, as well as connectors for balanced and unbalanced output signals. Inside the head are additional switches for 10 dB attenuation and the high-pass filter.
The KU 100 dummy head is a replica of the human head with a microphone built into each ear.
When the recorded audio signal is reproduced through high-quality headphones the listener perceives a sound image almost identical to the one he would have heard at the recording location of the dummy head (head-related stereophony).
When played back through loudspeakers, the sound matches to a high degree that of conventional stereo microphones, placed in the same position. However, a superior quality is added, that of a distinct spatial depth perception.
The KU 100 dummy head is just as easy to use during creative radio drama productions, and music recordings where the room acoustics should be recorded at the same time.
The dummy head is also contributed essentially as an important tool to preserve natural sounds of all kinds. In addition, the dummy head is frequently used to examine and document the influence of noise in industrial applications at various working places under realistic conditions.
The KU 100 uses transformerless circuitry with the advantage of high output capability, fast transient response, and extremely low self noise. The usual output transformers are replaced by electronic circuits. As with traditional transformers, this technique ensures good common mode rejection, and prevents RF interference, that may influence the balanced audio signals.
The dummy head provides balanced (XLR) and unbalanced (BNC) outputs. It can be powered in three different modes: from an external P 48 phantom power supply, with batteries as part of the internal battery supply, or from an external AC mains supply (included with the system).
Filter and attenuation
A 10 dB switch inside the head attenuates the sensitivity. A second switch selects the cutoff frequency of the high-pass filter to be either linear, 40 Hz, or 150 Hz.
The KU 100 comes in a robust aluminum carrying case, together with an external power supply unit, a 5-pin XLR cable, and an adapter cable that splits the 5-pin XLR output into two 3-pin XLR connectors.