Voice Coil Focus: Quasi-Alignment Families

This article is another great contribution by Claus Futtrup, this time with direct support from Jeff Candy, the two creators of Speakerbench, the free to use web-based application for low-frequency analysis and design of loudspeakers. Another follow-up article for the Bass Reflex Alignments article series that was published in audioXpress and Voice Coil, this time, the authors discuss the important Quasi-Alignment Families where the fundamental idea is trying to approach a roll-off similar to the Butterworth B4 alignment (a maximally flat response) but compatible with real systems for which the driver Qt will not allow a true B4 alignment.

In the first part of this work, the authors discussed the difficulties in estimating cabinet losses using the classical Thiele-Small framework, and proposed a solution using an advanced transducer model. In this second article, the authors detail how their Speakerbench web-app offers an accurate and practical approach to this problem, and demonstrate how users will be able to easily and accurately determine the best suitable box volume for a loudspeaker system. This article was originally published in audioXpress, September 2021.

The two authors investigate leakage loss as identified with an advanced transducer model and verified with measurements. This is compared to classical Thiele-Small modeling with the intention to motivate the reader to further explore advanced parameter estimation and box simulation with the Speakerbench Speaker Design Calculations online tool. This two-part article concludes with an overview of how Speakerbench offers an accurate and practical approach to this problem. This article was originally published in audioXpress, August 2021.