At 634EARS, one of the most important principles in earphone design is to perfectly align the direction in which the driver outputs sound with the direction of the nozzle—the sound exit.
This concept of driver alignment was one of the key themes in the housing design of the new model, ROXA-S100.
How Driver Orientation Affects Sound
When using a single dynamic driver, aligning the driver’s sound output direction with the nozzle’s direction has a major impact on the accuracy of the high frequencies.
If the two directions are misaligned, the high frequencies become significantly attenuated.
This is because higher frequencies are more directional, and any obstruction in their path can cause a noticeable loss of energy.
“Lacking Highs” vs. “Controlled Highs”
During final tuning, it’s common to slightly tame the highs using a filter placed inside the nozzle.
However, there’s a clear difference between “controlling highs that are already fully present” and “highs that never come out due to structural limitations.”
Even if they might sound similar in balance, the former has openness and transparency, while the latter feels closed and “ceilinged,” as if the sound cannot fully breathe.
The Dilemma Between Fit and Sound Quality
With a 10mm dynamic driver, achieving a perfect alignment between the driver’s output direction and the nozzle direction is not easy.
When the driver is positioned at the correct acoustic angle, the nozzle naturally shifts slightly backward from the front of the face, which can reduce the sense of comfort and fit.
If the driver’s angle is ignored in favor of comfort, the earphone may fit better in the ear—
but the trade-off is a loss of sparkle, openness, and high-frequency clarity.
A New Design Balancing Sound and Comfort
For the ROXA-S100, the housing structure was redesigned completely from scratch to balance sound quality and wearing comfort.
While maintaining the principle of perfect driver–nozzle alignment, I adjusted the internal structure dozens of times to improve fit and ergonomics.
Development started early this year, and it took more than six months of trial and error to finally reach the ideal shape.
A Design Born from Trial and Error
Many earphones on the market share similar shapes—and some even look identical.
Indeed, it would be easy to create a new product quickly by imitating existing designs.
But I believe that true craftsmanship lies in creating through one’s own experimentation and process of discovery.
Even if an original design ends up looking similar to others, the fact that it was built through one’s own testing and refinement makes all the difference.
That’s what matters most in creating something genuine.
The housing design of the ROXA-S100 was born from this belief, refined through countless tests.
It may not be perfect yet, but it represents the shape of a true challenge—an honest pursuit of both sonic precision and comfort.
If this story resonates with you, I hope you’ll take a closer look at this earphone and experience the sound born from such dedication.