While HypetheSonics’ main headphone database contains measurements of multiple headphones using a single coupler, this research database exists to assess the couplers themselves. Various IEC standard, 711 clone couplers and newer (non-IEC standard) devices are considered against a relatively small number of in-ear monitors and human-subject measurements. (Note, ‘MM’ refers to the given IEM with a mems microphone installed in its eartip. This procedure changes the overall frequency response, which should therefore not be compared with the standard, non-MM measurements.)

We gratefully acknowledge the work of the numerous ASR, Discord and head-fi members who contributed to this project.