9OPC crossover™ (Optimum Phase Crossover)

User manual Utopia Be line

The crossover is a key element in the design of a loudspeaker. Its role and

its development are very complicated, the personality of a loudspeaker depends on it.

The role of the Crossover

The crossover has the function of distributing the signal from the amplifier to the various drive units in a loudspeaker: bass, midrange and treble. The most critical area of filtering this signal, with out any doubt, is between the midrange and treble. A low-pass filter rolls off the higher frequencies of the midrange. A high-pass filter rolls off the low frequencies from the tweeter. This crossover point generally occurs in the region between 2-5kHz. This underlines a fundamental point in terms of realistic sound reproduction: “directivity”.

Mastering Directivity

The diameter of a drive unit designed to reproduce midrange frequencies is generally between 130 and 170mm. These dimensions correspond to a frequency of between 2 and 2.6kHz. The directivity, meaning the angle over which a drive unit will radiate its energy, reduces as frequency increases. For frequencies where the wavelength is smaller than the diameter of the cone, the sound becomes very directional. This means that the sound will be radiated in an increasingly narrow beam. As a consequence, the acoustic power radiated from the loudspeaker is not evenly balanced, principle criterion for the reproduction of a realistic image over a three dimensional space.

Here our inverted dome tweeter offers a unique advantage in that its design and conception allow it work down to frequencies sufficiently low enough to avoid the effects of midrange beaming.

Mastering Phase

In addition to the constraints imposed on the tweeter at low frequencies, there is also another very critical aspect: the phase behavior of the loudspeaker and crossover combination in this critical region. The ear and the auditive system are extremely sensitive in the zone 2-2.5kHz. The midrange drive unit and its crossover must display an amplitude response that is “the exact mirror image” of that of the tweeter and its crossover. For this criterion to be met, the phase between the midrange and tweeter must be perfectly matched for the two to overlap and sum perfectly and

create a balanced tonality. The difference in phase between the tweeter and midrange at the crosso- ver point must be zero. Thus, there is total summation between the two emission sources

at the crossover frequency. Out of phase, the loudspeaker should show a very deep and symmetrical hole in the response curve.

OPC Technology

These aforementioned steps form the basis of OPC technology. However, it would be naive to think that this ideal could be reached simply through an extensive development of crossover technology. It is necessary to have total control over the response and performance of the transducers themselves, as is only possible for a few manufacturers who develop their own drive units as Focal-JMlab: a specific drive unit is developed for each individual type of product. It's unrealistic to think that a mechanical deffect can be corrected electricaly.

With the OPC technology, we use an acoustic roll-off of 36dB/Octave for the slopes between midrange and tweeter along with a perfectly aligned phase. This translates into a sound that is extremely coherent and with a natural timbre. Imaging is extremely precise and at the same time dispersion wide so that the result can be enjoyed over a wide listening area.

The high and low pass crossover sections “calibrate” the electrical signal perfectly optimizing the range of frequencies passed to each drive unit.

5 000Hz

2 500Hz

A bass-mid drive unit will radiate sound in an increasingly directional manner as frequency increases. It becomes more directive. Therefore the crossover should introduce the tweeter before this phenomena starts to take effect.

Frequency response in and out of phase. The Grande Utopia shows a perfectly symmetrical cancellation out of phase indicating a perfect optimization of phase.

The OPC crossover offers a remarkable impulse response, even on a 4-way loudspeaker like the Grande Utopia Be.

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Focal Utopia Beryllium Line user manual Role of the Crossover, Mastering Directivity, Mastering Phase, OPC Technology
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Utopia Beryllium Line specifications

The Focal Utopia Beryllium Line represents the pinnacle of headphone technology, combining cutting-edge materials with sophisticated design to deliver an unparalleled listening experience. Renowned for their audio fidelity, these headphones have become a benchmark in the high-end audio market, attracting audiophiles and casual listeners alike.

At the heart of the Utopia series is the innovative beryllium driver. This unique material has been chosen for its exceptional rigidity and lightweight properties, which allow for precise sound reproduction across a wide frequency range. The beryllium dome used in the drivers is lighter than traditional materials like plastic or aluminum, contributing to a rapid response and minimal distortion, even at high volumes.

Another hallmark of the Utopia Beryllium Line is its open-back design, which enhances the listening experience by creating a natural and immersive soundstage. This design allows air and sound to flow freely, resulting in a more open and airy sound. Listeners are treated to an expansive audio landscape, with instruments and vocals feeling as if they are placed in a three-dimensional space.

The Utopia headphones also incorporate Focal's "M" shape dome technology, which optimally shapes the driver to provide an extended frequency response. This technology ensures that the headphones deliver rich bass, detailed mids, and sparkling highs. The frequency response ranges from a low of 5 Hz to a high of 50 kHz, allowing listeners to experience the full spectrum of sound.

Comfort is another critical aspect of the Utopia design. The headphones feature soft memory foam earpads and a lightweight structure that ensures long listening sessions can be enjoyed without discomfort. The headband is made from high-quality materials, contributing to both the aesthetic appeal and the longevity of the product.

Further, the Utopia Beryllium Line boasts a striking aesthetic, with a luxurious look that includes genuine leather and an elegant, modern finish. The combination of form and function makes these headphones not just a tool for listening, but a statement piece for any audio enthusiast.

In summary, the Focal Utopia Beryllium Line stands out for its revolutionary use of beryllium in driver technology, open-back design, and commitment to comfort and aesthetics. These features come together to create a transcendent auditory experience, setting a high standard for what audiophiles can expect from premium headphones. Whether for casual listening or critical listening sessions, the Utopia Beryllium Line is engineered to impress.
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