- Written by Piero Gabucci
- Published on 03 December 2013
Design of the THIEL CS2.7 Floor-standing Speakers
The CS2.7 is unmistakably a Thiel; anyone familiar with the CS line-up will recognize the styling. Design aside, Thiel emphasizes that old adage, form and function; technically critical and reinforcing the notion of pushing successful fundamental ideas forward. Inert speaker enclosures, driver design, there is nothing in this speaker that should surprise anyone.
The CS2.7 is a 3-way speaker standing about 42" tall with the carpet spikes and no lightweight at 77 pounds. The cabinet shares the same construction of the CS3.7 with multiple laminated layers of bent plywood, not MDF most commonly used nowadays because of the ease of CNC machining. The overall construction is impeccably detailed. The dark cherry veneer on the sides and base is beautiful as it curves around to the front where it meets the grill fabric. Although they avoided the transition from horizontal to vertical on the top by placing a black matt finish that also runs down the back of the speaker. Frankly, I actually like the design of the CS2.7 over the 3.7, but that's just me.
The face is slightly sloped back I'd say about 15 degrees, thereby angling the front baffle tilting the driver's axis alignment so that the sound reaches your ears at the same time. This is critical in the concept of time coherence. Likewise, the front baffle curves away on the sides reducing edge refraction and also tapers from the floor on up allowing for more space on the face for the larger woofer driver – form and function.
Most times you don't hear much about the screen grill, but Thiel has designed it flush to the face, like a windshield on a car these days. It's recessed enough for the cleanest of detailing and unlike most speaker grills held in place by pressure pegs, Thiel achieves the detail by holding it in place with magnets.
The heart of the driver compliment on CS2.7 is the heart of Thiel in the tweeter/midrange driver known as the coaxial/coincident design – the 1" tweeter and 4.5" mid-range are aligned with the tweeter within or more accurately, centered. Both drivers are aluminum for stiffness and reduced mass, thus improving speed and accuracy. Sitting in a die-cast chassis, they also share very powerful neodymium magnets which contribute to lowering distortion by keeping the throw distance short. Most noticeable however is the corrugated design of the mid-range cone, the ribbed diaphragm is stiffer, reduces coloration and provides for an even frequency response.
Although not on this speaker, Thiel does employ similar design and technology in larger woofer using very strong, rigid aluminum in a "star" design found on the CS3.7. On the CS2.7, the 8" aluminum woofer with a 2" diameter voice coil is complimented by a passive "racetrack" shaped radiator.
The plain rear sports a single pair of quality binding posts, properly placed down low. Fully adjustable carpet spikes anchor the CS2.7's to your floor covering.