The Secret Life of Loudspeaker Flex Wire

This valuable tutorial on speaker lead-out flex wire by Mike Klasco revisits the fundamentals, from the trailing ends of the voice coil winding to speaker terminals. How to avoid flex wire whipping, fracturing of lead-out conductors, thermal issues, and corrosion of the solder joints. What types of flex wire and wire gauges are available, what are the advantages of textile fibers and wire testing, are some of the topics addressed. This article was originally published in Voice Coil, April 2024.

This Test Bench explores the exciting SEAS W16NX005 5.25" Metamodal TPCD Midbass Woofer. Part of the SEAS high-end Excel line of transducers, the W16NX005 is the first commercial product available that combines the latest Composite Sound metamodal TPCD diaphragm technology with the typical SEAS high-performance Excel woofer motor design. This midbass woofer includes a metamodal diaphragm and 2" convex dustcap, along with an optimized NBR surround and black cloth flat profile spider for compliance.

From the experienced hands of Andrew C. Russell, of Hifisonix fame, comes the ax-Amplifier, a Class A design that uses Augmented Feedback Error Correction (AFEC) to achieve ultra-low distortion and improve key audio performance parameters without adding too much complexity and cost. Published in two parts, the first article addresses the amplifier design in detail, with Part 2 detailing the power supply system and conclusion with measurements. This article was originally published in audioXpress, April 2024.

Another exciting driver from Neotera, the UF 295 CBS is a new ultra-thin 10" subwoofer primarily intended for high-quality applications in home audio or automotive systems. The UF 295 CBS impresses immediately with its single piece black anodized concave cone assembly suspended by two large rubber surrounds, one on each side, not using a spider for compliance. The cone is driven at its perimeter by a large aluminum voice coil and a unique motor structure of 72 neodymium bar magnets, covered by no less than 10 international patents. This article was originally published in Voice Coil, April 2024.

This excellent thought piece by loudspeaker industry veteran Tom James, addresses the often disregarded topic of speaker measurements and the corresponding variables of SPL Graph Data. In his short essay James explores the impact of ignoring or intentionally manipulating the rules established in the "Scales and Sizes for Plotting Frequency Characteristics and Polar Diagrams," defined in the IEC-602632 standard, originally from 1982 and updated in 2020.

Frequency response is not the only important factor in testing in-ear headphones, and instead, the listening experience is largely influenced by how the pressure field is built up in the semi- or fully closed ear simulator, making leak and insertion position overshadowing parameters. This article shares the simulation work to assess the pressure field and its impact on different ear canal geometries, with surprising conclusions, fundamental to ensure consistency and repeatability when characterizing in-ear devices.

This article, written by the experts in optical MEMS microphones from sensiBel expands on the technologies that will undoubtedly contribute to making the next generation of hearables and advanced audio systems. As the Norwegian company enters the market with its first-generation products, the authors explain how 80dB SNR optical MEMS microphones will enhance Microphone Array Beamforming and the different types of beamforming algorithms.

In Voice Coil April 2024, Tom James reminds us about the importance of SPL Graph Data, and Mike Klasco revisits the fundamentals of speaker lead-out wire. As scheduled, there's an updated directory of Speaker Cable and Connector Vendors. James Croft explores a patent detailing a filter that may increase and extend the bass frequency response of a speaker. And for this month's Test Bench, Vance Dickason characterizes the Neotera Ultraflat UF 295 CBS 10" Subwoofer, followed by the SEAS W16NX005 5.25" Midbass Woofer with a metamodal TPCD diaphragm.

Read the latest Earbuds and Hearables market update. sensiBel experts explain everything about the advantages of Microphone Array Beamforming with Optical MEMS Microphones. GRAS' researchers share their findings about Ear Canal Geometry for In-Ear Headphone Testing. Learn how Hearing and Audio affects our perception of music fidelity. Jan Didden interviews Menno van der Veen. Andrew Russell shares his High-Performance 60-Watt Class A Amplifier project, and Tom Perazella explains how to build a Comprehensive AC Power Controller.