All items written by Geoff Hill

The IEC 60263:2020 Standard - Is a Picture Worth a Thousand Words?

February 1, 2024 by Geoff Hill

The IEC 60263:2020 Standard - Is a Picture Worth a Thousand Words?

With the proliferation of different electronic formats and screen grabs, aspect ratios, scales, and sizes for plotting frequency characteristics and polar diagrams, presenting audio measurement results in a clear and informative way is an even greater problem today than in the past! Geoff Hill explains what there is to know about the IEC 60263:2020 updated standard: Rules for scales and sizes for plotting frequency characteristics and polar diagrams... and what could go wrong.

Test Chambers for Accurate and Repeatable Measurements: The New Normal Even for Unique Projects

March 23, 2023 by Geoff Hill

Test Chambers for Accurate and Repeatable Measurements: The New Normal Even for Unique Projects

Hill Acoustics was approached by a company with an interesting problem. To accurately acquire measurements from a prototype that had an array of microphones to detect music coming from various angles of incidence and needed to operate over the full audio frequency range. Having seen Hill Acoustics' Tetrahedral Test Chambers and the results they could deliver, could Hill Acoustics help with this challenge?

Speaker Measurements: Replacing IEC 60268-5 (Part 2) - The Importance of Measurements

February 1, 2023 by Geoff Hill

Speaker Measurements: Replacing IEC 60268-5 (Part 2) - The Importance of Measurements

This article concludes the examination by Geoff Hill of the work taking place on loudspeaker measurement standards, and the progress the International Electrotechnical Commission (IEC) has made with its update efforts, also resulting from the work of the Audio Engineering Society's Standards Committee. We learn how these new standards apply to measurements of sound in 3D space and in production environments, SPL using voltage sensitivity, and the measurements of microspeakers. This article was originally published in audioXpress, October 2022.

Speaker Measurements: Replacing IEC 60268-5 (Part 1) - What Comes Next and Why

January 25, 2023 by Geoff Hill

Speaker Measurements: Replacing IEC 60268-5 (Part 1) - What Comes Next and Why

Geoff Hill, the inventor of the Tetrahedral Test Chamber (TTC), a member of the international Electrotechnical Commission’s standards 60268-21-2018 and 60268-22-2020, and part of the IEC Working Group TC 100/TA 20/PT 60268-22 on electrical and mechanical measurements on transducers, summarizes the progress happening on loudspeaker measurement standards. This is the first of two articles, appealing directly to all loudspeaker designers and manufacturers. This article was originally published in audioXpress, September 2022.

R&D Stories: The Tetrahedral Test Chamber Story (Part 2) - Consistent Loudspeaker Measurements

January 3, 2022 by Geoff Hill

R&D Stories: The Tetrahedral Test Chamber Story (Part 2) - Consistent Loudspeaker Measurements

In this article Geoff Hill completes the Tetrahedral Test Chamber story, a concept born out of necessity, simple wavelength theory and Beranek's wedges, measurement theory, and building upon experience gained in designing chambers in Europe, US, and Asia. These chambers are now in use throughout the world, providing consistent, reliable, and accurate measurements of loudspeaker transducers and loudspeaker systems. This article was originally published in audioXpress, October 2021.

R&D Stories: The Tetrahedral Test Chamber Story (Part 1) - Recognizing the Need for Consistent Measurements

December 29, 2021 by Geoff Hill

R&D Stories: The Tetrahedral Test Chamber Story (Part 1) - Recognizing the Need for Consistent Measurements

This article revisits the story of the development of the Tetrahedral Test Chamber (TTC), by Geoff Hill, loudspeaker engineer, author, and inventor, in an effort to solve the longstanding problem of making consistent loudspeaker measurements. This innovative loudspeaker test chamber is now defined in international standards and in use throughout the world, scalable to any size of loudspeaker driver. This article was originally published in audioXpress, September 2021.

Practical Test & Measurement: Loudspeaker Measurements at Home - A Guide for Building Your Own Test Chamber

September 9, 2020 by Geoff Hill

Practical Test & Measurement: Loudspeaker Measurements at Home - A Guide for Building Your Own Test Chamber

Our friend Geoff Hill, the inventor of the original tetrahedral test chamber (TTC), explores how to do loudspeaker measurements at home. For those of us without an anechoic chamber at home, Hill explains how to build our own test chamber. With the build description, he also provides a valuable guide on alternative loudspeaker measurement techniques. This article was originally published in audioXpress, September 2020.