More than Beryllium

Due to its incredible rigidity, Beryllium represents the ultimate material for a tweeter dome. Where soft domes turn choirs into grain, hard rock into noise, Beryllium can separate the complex harmonics with ease and keep the music clean and precise, also at high listening levels. But we do not stop there. Opting for an unconventional approach, we mount the dome flush with the baffle, as opposed to the typical recessed placement, allowing the dome to unleash its wide off-axis response without obstruction—vital for achieving an expansive, open sound. This unique dome placement is a rarity, demanding meticulous baffle rounding to prevent diffraction and a more intricate crossover design. However, the resulting benefits outweigh the challenges. Complementing this design, we employ an exceptionally narrow surround to eliminate any lingering "soft dome" coloration. With a mere 0.1-gram moving mass and a magnetic flux density of 2.0 Tesla, our high frequencies reach reference-level quality.

A Metamodal Membrane

A what?? Let me explain. The Swedish company Oxeon invented a unique process to produce a very flat uni-directonal fiber tape. A weave made with this tape can be very flat and therefore requires less resin and weighs less compared to a traditional fiber weave. In other words, more carbon fibers can be used for the same weight. In fact, Textreme as it is called, is so stiff that the familiar edge resonance around 1-2 kHz is eliminated. This stiffness usually comes at the cost of severe resonances at higher frequencies which limits the operating range. But by optimising the thickness and stiffness, the Textreme membrane is engineered for a controlled resonant behaviour by distributing the break up modes, a metamodal membrane. These distributed modes, or resonances, are far less severe and the useable frequency range is increased. It is the perfect membrane for a midrange loudspeaker. The sound it produces is entirely free from resonance, delivering an exceptional combination of purity, neutrality, and speed.

Fast and Powerful

Even the untrained eye will be able to see that this is not just another 10" woofer. It is purpose built for large deflection with minimal energy storage. In other words, it is powerful, fast and detailed. The strikingly large double magnet is mounted on a very stiff cast aluminum chassis and both magnet and chassis are designed for optimum airflow and ventilation. This minimises unwanted energy storage, just like the non-conducting vented voice coil and low damping rubber surround. The large surround and long voice coil allow a very high mechanical deflection of 22mm and a special designed spider limits the mechanical excursion when the woofer reaches the maximum deflection. The very high currents needed to bring this woofer close to its maximum require the large area of the 3” voice coil for sufficient cooling.

Internal Acoustics

Internal resonances can manifest audibly through the speaker membranes, and various effective countermeasures have been implemented in the Reference One. The baffle edge behind the mid-range driver is chamfered to mitigate the potential cavity resonance within the speaker cutout. Additionally, two internal Helmholtz absorbers have been strategically incorporated: one absorbs the standing wave between the cabinet's top and bottom, while the other tackles the bass reflex port resonance. The placement of the bass reflex port inlet has been carefully chosen to ensure that it operates in an area where the influence of any remaining internal resonances is minimized. Moreover, the top opening has been designed to prevent the excitation of listening room resonances that typically occur between the floor and ceiling. This seemingly simple yet effective measure holds significant potential for improving sound quality in various listening rooms, as these resonances are often challenging to control. Finally, the design of the bass port is corner-less and features a substantial area, accounting for 30% of the woofer membrane. This design choice serves to minimize port turbulence and maintain linearity in output, even at high signal levels.

the Making of

The development and production of a Reference One loudspeaker entail several crucial steps, as showcased in this film. Comprehensive 3D computer drawings (CAD) containing all details are forwarded to our suppliers for the fabrication of most parts. However, certain components are crafted in-house utilizing advanced 3D printing and engraving methodologies. Delicate handwork is employed for assembly and the meticulous application of leather. Precise measurements play a pivotal role throughout the development process, while exhaustive listening tests serve to finalize the product.