Technical & Applied Article

Group delay-driven crossover optimization for subwoofer satellite systems at listening position

Department of New Media Music, Sangmyung University, Seoul, South Korea

^* Corresponding author: joe45294529@gmail.com

Received: 22 April 2025
Accepted: 15 July 2025

Abstract

This study explores the influence of crossover frequency on frequency response (FR) irregularities in 2.1-channel subwoofer-satellite systems at listening positions, introducing a data-driven optimization approach that focuses on minimizing the maximum absolute group delay (max|GD|) in low frequency range. While subwoofers paired with satellite speakers are increasingly employed for low-frequency reproduction, the role of phase-related effects, such as group delay (GD), in contributing to FR inconsistencies like amplitude dips has received limited attention in prior research. Experiments were carried out in two different rooms, with FR and GD analyzed over a crossover frequency range of 40–140 Hz. The findings suggest that minimizing max|GD| could reduce FR irregularities, with results from a Fixed Effects model indicating a statistically significant positive relationship between max|GD| and Δ_GD-SPL (coefficient: 22.274, p-value < 0.0001). An optimization algorithm is proposed to identify a crossover frequency that minimizes max|GD|, offering a phase-focused approach that may enhance low-frequency reproduction for practical applications like studio monitoring and home audio.