Adhesives, Coatings, Sealants, Dispensers, Patents and More Loudspeaker Topics in Voice Coil July 2020

June 26 2020, 12:35

This edition of Voice Coil features an article by industry consultant David Lindberg (DB Enterprise HK, Ltd.), titled "Unravelling the Technical Solutions in Waterproofing of Audio Devices." This interesting exposition visits the challenges and solutions that the electronics industry in general and the audio industry specifically needs to consider when requirements for waterproof, moisture-proof, splash proof, weather-resistant, and sweatproof are increasingly demanded by consumers. "With everyone owning several electronic devices, most of us have experienced sweat damage on our earbuds, drinks spilled on our notebooks, or worse a phone in the toilet; or in the case of loudspeakers, crossover circuit boards in outdoor vented products. While the marketing points on the box might claim IPx7, IP68, or sweat proof, from a manufacturing perspective, there are gaps in the different processes to achieve these standards." Lindberg discussed this topic in our weekly e-newsletter The Audio Voice, and now expands it for this edition of Voice Coil, explaining mechanical design and coating approaches, with a loudspeaker-focused perspective.

And this is also the topic of July’s Directory, compiled by Mike Klasco and Nora Wong (Menlo Scientific, Ltd.) on Adhesives, Coatings, Sealant, and Dispenser Providers 2020. This is one of the more comprehensive and useful resource directories published by Voice Coil on this key perspective for loudspeaker design and manufacturing.

In Acoustic Patents, James Croft (Croft Acoustical) reviews an "Apparatus for Managing Distortion in a Signal Path and Method," an apparently wide-ranging invention credited to Gregory K. Cambrell (Mulgrave, Victoria, AU) and Zeljko Velican (Endeavour Hills, Victoria, AU), on behalf of Blueprint Acoustics, Pty. Ltd. This patent claims a variety of techniques and implementations to manage and/or reduce harmonic distortion components arising along a signal path associated with an audio signal or audio system, using phase manipulation. Familiar with Blueprint Acoustics and the work of this Australian audio company that has been exploring interesting audio technologies for over a decade driven primarily by the credited researchers, Croft looks in good detail at all the implications of possible embodiments for the patent, which might signal a path for evolution into practical and advanced designs.

In this edition of Test Bench, Vance Dickason characterizes the recently announced SEAS L19RNX1 woofer from the company's new Prestige Titan Series. The L19RNX1 is the second woofer in this new 19 cm series of SEAS woofers, the first being the W19NX001 Excel Graphene-coated magnesium cone woofer. All drivers in the new SEAS Prestige Titan line feature FEA-optimized motor systems, copper caps and shorting rings, and titanium voice coil formers in combination with matte black aluminum cones. The L19RNX1 7” woofer features a proprietary injection-molded aluminum frame with six narrow spokes, a lightweight curved-profile matte black aluminum cone, a radial reinforced NBR surround, and uses a frame that is completely open beneath the spider mounting shelf, and with a small 12 mm diameter pole vent, so substantial air can be pumped past the voice coil and over the front plate.

The second driver in Test Bench is an interesting home audio tweeter from Creative Sound Solutions (CSS). CSS Audio was founded in 2001 and is operated out of the Southeast Michigan area by two friends with a passion for great audio. Ownership of CSS was transferred from Bob Reimer, the original founder, to Kerry Armes and Dan Pointsett in 2017 and they’ve been working on bringing back some of the drivers CSS is known for, like its high Xmax XBL dual gap woofers, which are still part of CSS OEM lineup. The company designs its own line of OEM woofers and tweeters, which it also uses to manufacture complete speakers and speaker kits branded under the CSS name. CSS sent Voice Coil its latest high-end tweeter, the LD25X, a special driver with a unique dual-gap patented XBL2 motor. CSS licenses the XBL2 technology from inventor Dan Wiggins for two of their woofers and for the LD25X tweeter. The XBL2 motor features a short voice coil traveling between two gaps, allowing for a higher Xmax than most conventional motors can provide. The LD25X tweeter features a 25mm silk dome diaphragm and flat silk surround, in a 73 mm diameter six screw cast-aluminum faceplate anodized semi-flat black.

Industry Watch also includes interesting updates from Klippel, Loudsoft, and the latest from the Audio & Loudspeaker Technologies International (ALTI) association.

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