Fasten Your Seatbelts. Knowledge for Speaker Designers Now Available in Voice Coil September 2025

In this issue of Voice Coil, you can’t miss Mike Klasco’s history lessons and situation report on speaker magnets and rare earth materials, his updated Directory of Materials Manufacturers for Consumer Audio Products, and subdirectory on Transducers for Soundbars and Bluetooth Speakers. Vance Dickason’s Test Bench characterizes the new BGW-D182-86-4-001 glass cone woofer from Glass Acoustic Innovations Technology (GAIT), followed by the W 174.38 Fibonacci woofer from RS Speakers, both being 6.5” drivers with innovative approaches.

Read the report of the High End 2025 show in Munich, the latest report about Connected Home Audio and Home Theater, and Gary Eickmeier's thought-provoking perspective on An Image Model Theory for Stereo. Learn about Phase Delay, Group Delay, and Circuit Sensitivity Basics, the Dante Virtual Soundcard Pro software, the Universal Audio Apollo x16D audio interface, and the essentials about Audio-Speech Processing and Microphone Arrays. Tom Perazella designed a filter for a SMPS, and Richard Honeycutt explores options to build a tube guitar amp.