Leading professional audio manufacturers Nugen Audio, RTW, Steinberg and Telos Alliance have teamed up with Fraunhofer IDMT to establish a common approach to measuring and presenting dialogue intelligibility across broadcast, production and postproduction environments. The companies have formed the LEAP Meter Manufacturers Group (LMMG) and, with Fraunhofer IDMT, developed the LMMG Dialog Intelligibility Implementation Agreement.
The initiative addresses dialogue intelligibility across TV, radio, streaming, podcasts and other speech-based media.
Measurements such as level and loudness provide essential information about an audio signal, but do not directly indicate how readily listeners understand speech. LEAP adopts an alternative approach by estimating the listening effort required to understand dialogue, providing an objective indication of perceived dialogue intelligibility.
As LEAP is integrated into products from different manufacturers, the participating companies identified the need to ensure that users receive comparable results regardless of which product or platform they are using.
Although products may use the same underlying algorithm, differences in signal processing, downmixing, scaling, smoothing, terminology and visualisation can otherwise lead to differences in how measurements are presented and interpreted. The LMMG Dialog Intelligibility Implementation Agreement establishes a shared set of recommendations designed to provide consistency across implementations.
Under the agreement, participating manufacturers have standardised key aspects of their implementations, including the use of Dialog Intelligibility as the common terminology and DIU (Dialog Intelligibility Unit) as the unit for customer-facing measurements.
LEAP results are mapped to a common scale from 0 to 100 DIU, with higher values representing better dialogue intelligibility and lower listening effort. The agreement also defines common reference thresholds and color ranges, signal processing and downmixing requirements, smoothing and the handling of non-dialogue content. The result is a common foundation that allows dialogue intelligibility measurements made using products from different manufacturers to be directly compared and consistently interpreted.
LEAP-based products are being developed for a wide range of applications, including live production, broadcast monitoring, post-production, quality control and content verification. The common implementation framework means that dialogue intelligibility can be assessed at different stages of the production and distribution chain using tools from different manufacturers while maintaining a consistent interpretation of the measurement.
A production could, for example, be monitored using one manufacturer’s solution, refined during post-production using another and subsequently checked during quality control using a third — all using the same underlying technology, scale and measurement principles.
Establishing this interoperability is a central objective of the LMMG initiative. The first version of the LMMG Dialog Intelligibility Implementation Agreement establishes the foundation for consistent real-time dialogue intelligibility measurement.
The growing importance of dialogue intelligibility is also reflected in the IBC 2026 Accelerator Media Innovation Programme. The Crystal Clear: Boosting Speech Intelligibility in Media project brings together broadcasters, industry organizations and research institutions to explore consistent and practical approaches to measuring and improving speech intelligibility across broadcast and streaming. While separate from the LMMG initiative, the project underlines the growing industry recognition of dialogue intelligibility as an important consideration throughout the media production chain.
The LMMG group intends to continue its collaboration as industry experience with the technology grows. Future work will include research into integrated dialogue intelligibility metrics that could characterize the intelligibility of complete programs or assets. Such measurements could ultimately provide broadcasters, streaming services and content producers with new tools for quality control and help establish dialogue intelligibility as an important complement to established audio measurements, such as loudness.
By collaborating on a common approach from the outset, Fraunhofer IDMT and the participating manufacturers aim to ensure that dialogue intelligibility measurements are consistent, understandable and useful across products and workflows, regardless of which manufacturer’s tools are used.
More: www.nugenaudio.com