MKH Story

The MKh STory
Page 9
The versatile MKH 800 TWIN
It is a well-known experience of sound engineers that microphone polar patterns may turn
out during or after recording to be sub-optimal, but changes are then no longer possible.
The MKH 800 TWIN, (launched in 2008) offers a smart solution to this problem. The TWIN
microphone is technically based on the MKH 800 and comprises the same twin-transducer
with its front and back cardioid polar-patterns. However, both transducer signals are not
combined inside the microphone to create a specific directional pattern but are available
separately at the microphone output. The signals are remotely mixed under monitoring
conditions by faders at the console. This is done as follows:
Route the signals of the front and back cardioids to adjacent faders. Then set the recording
level by the fader of the front cardioid. Preserve this fader position for the following (it is
assumed, for simplicity, that the fader position is 0 dB and that equal pre-gain is set for both
signals):
If the back cardioid fader is closed, then only the front cardioid pattern is activated. If the
fader is set to -10 dB then the wide cardioid (sub-cardioid / hypo-cardioid) results, as 30%
from the back cardioid is added to the front cardioid. At the 0 dB position both cardioids add
to make the omnidirectional pattern.
If the polarity of the back cardioid is inverted then at 0 dB fader position the figure-of-eight
pattern results by subtraction, and accordingly the super-cardioid is formed at the -10 dB
position by subtracting 30% of the rear cardioid.
As the rate of the rear cardioid can be altered continuously by the fader position, the directivity can subtly be
controlled from omnidirectional to cardioid, and with inverted polarity from cardioid to figure-of-eight. The directivity
pattern can smoothly be optimised by monitoring without noise and delay, even during a live performance.
The relative position of the rear cardioid fader always defines the back (180°) rejection of the resulting pattern,
which for instance is 10 dB for both wide cardioid and super-cardioid. Evidently, the polarity inversion of the rear
cardioid inverts also the polarity of the rear lobes of the resulting super-cardioid or figure-of-eight characteristics.
Some digital microphones also enable remote control of the directional pattern, but again both signals are
combined inside the microphone, and thus signal information is irretrievably lost. In contrast, the MKH 800 TWIN
maintains the total information in two channels. If both signals are stored this information is also available for
future applications. This opens a new dimension of recording practice as it provides maximum flexibility during
post-production, and eliminates the need for determining the microphone patterns before the recording session.
Stereo and surround sound productions can be mixed in parallel with differing directional patterns. Thus the
sound engineer is no longer forced to favour one or the other before recording. Due to the symmetry of the TWIN,
additional backward-oriented patterns can be generated, for instance for surround sound productions. MS and
double MS configurations with a laterally oriented bidirectional microphone (e.g. MKH 30) enable additional set-
ups. Optionally a centre channel can be generated with an arbitrary directional pattern. In all cases only three
microphone signals have to be stored for post-production.
Thus the creativity of the sound engineer is virtually unlimited. Moreover, the small size of the MKH 800 TWIN
enables optically unobtrusive applications. Obviously this microphone is the most versatile member of the MKH
line.