NTT DOCOMO BUSINESS, Inc（Head Office：Chiyoda-ku, Tokyo, President&CEO：Katsushige Kojima、(“NTT docomo business”) and NTT sonority, Inc.（Head Office：Shinjuku-ku, Tokyo, CEO：Hiroshi Sakai (“NTTS”)）are excited to announce that starting FY2026, the Premium Seats (private and semi-private compartments) on the Tokaido Shinkansen N700S cars will feature NTT’s patented “PSZ (Personalized Sound Zone)” technology through the provision of new audio solutions and an exclusive control system.
Those premium class seats are scheduled to be introduced to the public by Central Japan Railway Company (“JR Central”) and this will be the first case for NTT groups’ PSZ technology to be adopted in the public transportation sector and will offer a new experience to those Premium Class customers, allowing them to enjoy a private sound space without worrying about their surroundings while traveling.
(images shown above are for illustrative purposes only)
1.Introduction of PSZ Technology to Premium Class Seats on the Tokaido Shinkansen
Special speakers featuring NTT's patented "PSZ (Personalized Sound Zone)" technology will be installed on the headrest area of the premium class seats (private compartment type to be introduced in October 2026, and semi-private compartment type to follow in FY2027) on the Tokaido Shinkansen N700S. By wirelessly connecting to the customer's device, the sound of music, videos, etc., will be directed only to the customer's ears, allowing them to enjoy their experience comfortably without worrying about sound leaking to those around them. This technology is intended for a variety of users and scenarios, including businesspeople who want to conduct online meetings without hesitation, customers who value privacy, and those who want to relax without worrying about their surroundings.
2.About “PSZ (Personalized Sound Zone)” technology
PSZ technology minimizes sound leakage despite its open speaker structure by simultaneously emitting inverse sound waves to counter the original sound, enabling it to encapsulate the sounds close to the subject’s ears. This is the same technology featured on NTT sonority’s “nwm” and “cocoe” Open-Ear earphones and headphones, and in terms of its implementation in the public transportation sector, this project will be the first of its case.
※1 Technology developed by NTT computer and Data Science Laboratories
3.Solution Overview
NTT DOCOMO Business licenses PSZ technology, while NTT sonority provides comprehensive acoustic solutions, including the development of a control system that is suitable for equipping PSZ (※2) and acoustic design consulting(※3). We have collaborated with JR Central to conduct repeated tests in the unique environment of railway cars, and after confirming the technical feasibility of implementation, we have decided to proceed with this implementation.
※2 independently developed a dedicated processing board to maximize the performance of PSZ technology while fitting into the limited installation space of the seat’s headrest area.
※3 optimization of acoustic design for practical application, which includes speaker placement within individual cabins, evaluation of speaker units, and verification of the impact of seat upholstery materials on acoustic characteristics.
4.Future Developments
We view the adoption of PSZ technology on the Tokaido Shinkansen as an important step toward transforming travel spaces through acoustic technology. Building on this success of achieving individual acoustic spaces without any devices within the unique spatial constraints of public transportation, we will explore the development of solutions that contribute to resolving acoustic challenges not only in the railway field but also in various travel scenarios and public spaces, including transportation infrastructure.
