Invisible Tech – Enhancing audio immersion with CityUHK inventor

The traditional optimal audio experience depended on the interplay between space, speakers and music carriers, such as CDs or vinyl records. Invisible Tech, a local start-up specialising in acoustic design, uses recycled wine crates, wood waste and reclaimed furniture to produce a range of speakers. With the support of HK Tech 300 of City University of Hong Kong (CityUHK), Invisible Tech worked with CityUHK audio technology researchers to develop a sound system tailored for the modern living environment and habits. The system is designed to provide users with immersive surround sound music enjoyment.

Invisible Tech co-founders Henry Cheung Ngai-hang (first from left), Patrick Lee Pak-yu (second from left), Simon Chan (third from right), and Wan Cheuk-kit (first from right) with the inventor and technical advisor, retired Professor Peter Tsang Wai-ming of CityUHK’s Department of Electrical Engineering (third from left), and a representative of strategic investment partner KITS (second from right). (Photo source: Invisible Tech)

HK Tech 300, an innovation and entrepreneurship programme at CityUHK, is designed to support CityU students, alumni and researchers who are interested in starting their own business. It is also open to other young people who are eligible to participate in the programme by applying patented CityUHK technology in innovative products or solutions. Invisible Tech is one of the start-ups that has been invested in and nurtured by the HK Tech 300 Angel Fund.

Knowledge transfer from the inventor

Invisible Tech started as a final-year university project by the founding members. They carried out extensive testing to determine the effect of different materials on the reflection of the audio signal, using their own acoustic algorithms and sound field emitting structures. This was done in consideration of the space of the venue, among other factors, to create a recycled acoustic sound system that adheres to “environmental, social and governance” (ESG) standards by using recycled wood.

During their participation in HK Tech 300, the team searched the intellectual property database of CityUHK and identified a sound-related patent that was deemed suitable for application in their products. Mr Henry Cheung Ngai-hang, one of the co-founders of Invisible Tech, recalled, “This patented technology provides a spatial audio experience and enhances the immersive audio experience of the listener through the application of a two-channel audio system.” In addition to the traditional stereo sound effect, which allows the listener to hear the left and right direction of the sound, spatial audio allows the user to feel the distance and height of the sound, thus creating a three-dimensional sound effect. HK Tech 300 introduce the team to the inventor of the technology, Professor Peter Tsang Wai-ming.

Adapting research to meet market needs

Professor Tsang, a retired professor from the Department of Electrical Engineering at CityUHK, has specialised in digital audio research for many years. “There is a slight difference between the left and right ears when listening to sound,” he explained. “If we can recreate this ‘difference’, the brain can receive stereo sound as if it were present. My research and design is based on this technology.”

Invisible Tech’s STEM audio teaching kit, made from wine crates. (Photo source: Invisible Tech)

When Professor Tsang met the Invisible Tech team through HK Tech 300, he was pleased to share the details of his patented “Audio Spatial Effect Enhancement” technology to help the team design their prototype. The two parties had a productive working relationship from the outset. Through mutual exchange, they developed their second-generation product: an eco-friendly wooden speaker that plays audio directly from streaming platforms and achieves spatial sound.

Professor Tsang explained that his research began as an application programme (app) that required users to either record or download audio to their mobile phone or tablet. “The team recognised that today’s generation, particularly young people, are accustomed to playing music directly from streaming platforms rather than downloading music or song files beforehand,” he explained. “So we looked at how we could modify the technology to integrate it into the team’s sound system.” He also provided technical support to the team in designing bespoke sound effects for various sound systems.

The company has collaborated with UK Furniture Designer and Audio Engineering Firm – DOOLAB UK to co-developed an innovative and modern “audio furniture”, aiming to disrupt both the traditional audio and furniture markets. It has started working with retailers in Asia for distribution. (Photo source: Invisible Tech)

Compatible streaming for immersive spatial audio

Traditional audio equipment typically offers a superior audio experience due to the nature of the sound sources, which were usually stored on a physical device, such as a CD or vinyl disc in the past, or are downloaded to a personal device in the present. But the streaming process applies compression technology, which inevitably affects the quality of the sound.

Invisible Tech’s speakers currently utilise Bluetooth to receive audio from all streaming platforms. Professor Tsang’s patented technology enhances the spatial sound of music playback. The combination of the two allows the technology to be compatible with music playback from streaming platforms, in addition to traditional CDs, vinyl discs or personal devices.

Mr Patrick Lee Pak-yu, another founder of the team, commented, “The technology developed by Professor Tsang is open to all smart system platforms, and I believe that very few products on the market can achieve this kind of spatial sound without headphones.”

Professor Tsang’s technology requires only a two-channel system to achieve spatial sound effects, which means that the team’s product also breaks the traditional limitation of having to place multiple sets of audio devices. This makes it more suitable for more compact living environments such as those in Hong Kong, Japan and Singapore.

Invisible Tech uses recycled wine crates to create STEM audio teaching kits and works with schools and educational organisations to provide programmes for students to develop their creativity and environmental awareness. (Photo source: Invisible Tech)

HK Tech 300’s comprehensive financial and technical support

The HK Tech 300 programme not only provides Invisible Tech with financial support, but also facilitates the sharing of innovative ideas with patent inventors in terms of research and development, thus potentially achieving synergy.

Patrick believes that the HK$1 million Angel Fund support from the programme will enable the team to commercialise the technology and take the product to market faster. “Our goal is not merely to compete with other brands for quality sound. We are looking for breakthroughs in our areas of expertise, be it in speaker design or the patented audio technology provided by Professor Tsang. I am extremely grateful to Professor Tsang for his invaluable support and guidance, which has enabled the team to advance its technology to achieve the current results,” he said. Patrick and Henry described Professor Tsang as both a partner and a good friend, adding that it has been a great privilege to have the opportunity to gain insight from Professor Tsang and his research and development achievements through HK Tech 300.

Professor Tsang added that having taught at CityUHK for a considerable period of time, he would like to see the University’s technologies applied in industry. “To be honest, we had no inkling as to the final product nature when we first developed this spatial audio concept and filed for the patent. Hong Kong is currently on a path of innovation and technology development. But where can we source the best talent and technologies? Undoubtedly from the universities. The question is how to transfer the technology from university to industry. I believe that HK Tech 300 is an excellent channel for this transfer.”

At CES 2024, the largest global consumer electronics trade show, the team’s “Audio Furniture” attracted the interest of Best Buy, the largest electronics retailer in the United States, resulting in further discussion of potential business opportunities. (Photo source: Invisible Tech)

Commercialising on-the-ground research

Invisible Tech is currently engaged in the production of recycled audio equipment. This is achieved through the utilisation of recycled wine crates, wood waste and old furniture to produce audio equipment and STEM audio teaching kits. It also works with schools and educational organisations to foster creativity, problem-solving skills and environmental consciousness among students.

In the retail sector, the company has integrated its proprietary audio system into furniture, saving significant space and allowing users residing in compact apartments to enjoy an immersive audio experience through the product and related technology. The built-in audio furniture attracted the interest of Best Buy, the largest electronics retailer in the United States, at the world’s largest consumer electronics trade fair, CES 2024, earlier this year. The company has also initiated collaboration with retailers in Asia to reach the commercialisation stage.

Invisible Tech will continue to collaborate with Professor Tsang and anticipates the development of further innovations in the near future.

(May 2024)