ThielAudio CS 1.6

Quote from the Test in HH:
From the perspective of constructional highlights on particularly interesting candidate is the midbass CS 1.6 from the American high-end specialist Thiel. At first glance it would seem that the motor magnet is missing but after further examination you can see that it lies underneath the large dust-cap. This explains the extremely flat mounting depth of a mere 50 millimeters, which predestines this transducer for in-wall applications.

The cone and dust-cap are formed from a single piece of aluminum. This type of construction usually drives the production engineers crazy: Normally the voice coil is simultaneously centered in the gap by the spider and the cone. However here it only uses the spider, i.e. its mounted using one instead of two guides and then glued to the unit comprised of cone and surround. The reason that Thiel can pull this off without major difficulties or failure rates lies in the 76 millimeter voice coil the sheer size of which factually eliminates any tumbling or wobbling of the cone-coil-unit. Besides that, the coil is an underhung construction and very short, which aids in the low distortion and supports the wide reaching frequency response, while also making production easier.

The frequency response is flat up to 7000Hz, before the typical metal cone resonances make themselves heard. The relatively minimal dampening of the resonance together with the beaming characteristics indicate that the CS 1.6 should hand off to a tweeter at the latest around 3,000Hz with a 3rd order or steeper low pass filter. Additionally it is also recommended that the effects of the resonance be further mitigated through the use of a band stop filter.

The interpretation of the parameters indicates that the Thiel CS 1.6 is more of a midbass than a true low bass specialist. In a 14 Liter bass reflex loading the chassis can reach a low end frequency of 54 Hz. Alternatively you could use it in a sealed cabinet as a midrange with a low crossover point to a subwoofer.