Theile Trapezoid

Theile Trapezoid

The "Theile trapezoid" is also called the "cardioid trapezoid." It has two different names for the same thing.

Its setup is pretty straightforward and done quite fast, if you have all material at hand.

Dr. Günther Theile is a well-known tonmeister who has invented other great arrays, such as the IRT-cross and the OCT.

With this array, background sounds and noises are picked up, and direct sound is suppressed by more than 15 dB. Additionally, sounds coming from an angle are suppressed to a lesser extent, depending on the angle.
So this array is a great choice, if you are focusing on the ambience, background sound.

It may be used in combination with other arrays, e.g. OCT a Linear ORTF-3D and some others.

It may look a little weird at first, but pointing surround microphones backwards isn't a new concept.

For the best results, position the trapezoid as high off the ground as possible while ensuring it is secure.

If you're interested, you may find this tutorial and shopping list helpful.