124Floating structure on the rearside of the cymbalPorous-structured frameNoise comparison in the sound hallA specially built box for below-floor measurements to replicate the floor of a typical second-story wooden house was installed inside the sound hall at Roland’s facility. Prototype drums were placed on top of the box and a sound level meter installed inside the box to measure noise levels repeatedly. After having obtained data-based evidence, measurements were also taken in an actual residential setting. The noise transmitted to the floor below was confirmed to be equivalent to the sound of writing with a pencil or chatting in a whisper.Noise measurements in actual environmentsMeasurements were taken in the upper and lower floors of a lightweight steel-framed apartment owned by Roland. The VQD106 and the TD-07KV—a model commonly chosen for home use—were installed on the second floor, and noise levels were measured in (1) the same room and (2) the floor below. Results showed that the VQD106 reduced noise on the floor below by approximately 75%, confirming its exceptionally quiet performance.The CYQ-12 highly quiet cymbal The VQD106’s cymbal features a honeycomb rubber insert under the mesh and a porous structure on the bottom surface. The points of contact between the striking surface and the rearside of the cymbal feature a floating structure incorporating soft rubber to further enhance quietness.Striking surface with mesh × soft rubber compositeA product that’s quiet but offers the distinctive feel of actual drumming“For a manufacturer, it’s important to sell products,” says Kikuchi. “But our real mission is to address customer concerns and work with them to overcome challenges. I was determined to arrange a seminar that would make the most of the measurement techniques and data analysis expertise we had cultivated over the years.”The seminar covered the basics of soundproofing and vibra-tion control, including the properties of sound and vibration, methods for measuring floor impact sound and natural vibration frequencies, and countermeasures for sound propagating through solids and air. Focusing on noise and vibration measurement in residential settings, the key area of interest for Roland, the Rion team conducted an online seminar lasting about four hours, deliv-ering lectures to dozens of engineers.The seminar received high praise from Roland. About three months later, Rion received another request for a more specific technical consultation. In June 2022, Rion officially joined the project team for developing the quiet electronic drum kit. Kikuchi recalls the start of this project:“Among the many topics that emerged during the consulta-tion, one theme they were particularly eager to explore was how noise and vibrations from electronic drums on the second floor of an apartment building would propagate to the floor below. The key point in measurements like this is the relative position of the drums to the measuring instruments. At what distance and angle should the measurements be taken to ensure accurate results? It’s not enough to have a sound level meter—you must determine the appropriate measurement method, which varies depending on the target object and environment. So we visited the site ourselves and paid careful attention to the measurement location.”In developing this new product, there’s no doubt that quietness was the key challenge. But the product wouldn’t have enhanced the value of electronic drums if it didn’t consider playability—the quality of being satisfying to play—as well as durability.“You can drum on a kitchen sponge. That’s quiet, but it’s not an instrument,” explains Yohei Kunimitsu from Roland’s Mechanism Development Department, who also plays drums in an amateur band. “Our mission was to pursue quietness while achieving the highest possible playability as a musical instrument. That was the starting point.”Before joining Roland in 2021, he had practiced drumming at home with a custom-built setup to prevent vibrations from prop-agating to the floor below. Roland had been a dream company for him, and one day he decided to quit his previous workplace to join. During his job interview, he professed his passionate commitment to creating a quiet drum kit. On his first day at the company, he was assigned to the research and development team led by Toyono. The team, including Kunimitsu, who quickly became a valuable member, embarked on a period of trial and error. “Having Mr. Kikuchi visit our measurement site was a huge step forward,” con-tinues Kunimitsu. “He provided valuable advice drawing on his academic knowledge and expertise. Having him work alongside us through the actual process of using sound level meters on-site will definitely be a great asset in our future product development.”
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