Klippel KA3 Modules — Time Frequency Analysis

While Voice Coil Test Bench reviews only make use of the Large Signal Identification (LSI) data from the Klippel analyzer, the reality is that there is an amazing list of 30 modules available for the KA3 that are seriously valuable for transducer and system development. As space permits, I will be covering a number of these modules in future issue of Voice Coil. The first module in this series is the Time Frequency Analysis (TFA) module. This article was originally published in Voice Coil, October 2021

We're off to a great start in 2022. Starting with details about the promise of Iron Nitride (FeN) magnets, followed by an article about Liquid Injection Molding Silicon for Next-Generation Headphone Surrounds. Next up, James Croft reviews a surround speaker patent granted to Klipsch, and Vance Dickason characterizes the Satori MW13TX-4 TPCD-cone woofer from SB Acoustics and the high-power WF275BD01 10.75" woofer from Wavecor. All articles now available to read online, PDF and print.

We looked at the most-read articles of 2021 in audioXpress.com (including selected articles from Voice Coil magazine), and we created this Top 10 list of news stories and online articles. 2021 expanded slightly on the record-breaking year that was 2020 for audioXpress.com, in terms of number of visits and regular users of the website. Visitors from all over the world returned more often to read the more than 7,700 stories available. Which of the topics and stories published online in 2021 were the most popular? Here are the results!

This Test Bench focuses on Eighteen Sound’s latest ND2T, a 1.4” neodymium compression driver, combined for characterization with the XT1464 elliptical-shaped horn, also from Eighteen Sound. This ultra-compact compression driver features a 2.4” diameter edge-wound voice coil wound with aluminum wire on a non-conducting Nomex former with a proprietary treatment. This assembly drives a field-replaceable pure titanium diaphragm and proprietary tangerine radial phase plug design. This article was originally published in Voice Coil, October 2021.

This Test Bench explication characterizes the 15DS100 15” professional subwoofer from B&C Speakers. This new transducer from the Italian company is a very high power handling design, able to deliver 3kW continuous (1.6W nominal), thanks to B&C's latest generation of very long voice coils - a great asset in applications from discreet PA subwoofers to three-way PA speakers. The B&C 15DS100-4 uses a proprietary 12-spoke cast aluminum frame with cooling vents for the neodymium FEA motor, which uses a 4” four-layer voice coil wound with round aluminum wire on a non-conducting glass fiber former. This article was originally published in Voice Coil, October 2021.

This Test Bench combines three new 25mm high-frequency transducers from German brand BlieSMa into a single characterization: the BlieSMa T25S-6 Silk Dome, the BlieSMa T25B-6 Beryllium Dome, and the BlieSMa T25D-6 Diamond Dome. All three tweeters appear to be built on the same platform, but optimized for each diaphragm material, and all three share pretty much the same feature set. BlieSMa was founded in January 16, 2018 by former Morel and Accuton engineer, Stanislav Malikov. This article was originally published in Voice Coil, September 2021.

In the December 2021 edition of Voice Coil, Vance Dickason details the possibilities of the CrossLite+ DSP filter software, while James Croft reviews an interesting invention to improve the bass response in automotive audio applications. And this edition includes an updated measurement microphone directory, and two interesting low-frequency drivers on Test Bench, with the Dayton Audio Epique MMAG E150HE-44 subwoofer, and the powerful 10NW76 high-SPL woofer from B&C Speakers.

This edition celebrates 35 years of Voice Coil, the Periodical for the Loudspeaker Industry. We discuss a new earphone technology for Balanced Frequency Range, Mike Klasco writes about Subwoofers and Bass, and James Croft reviews a new loudspeaker patent from Tymphany. Finally, Vance Dickason places Purifi Audio’s PTT4.0X04-NFA-01 Home Audio Midbass, and Eighteen Sound’s AMT200P AMT driver and XMT200 waveguide on the Test Bench. Now available in print or download.

This article characterizes a coaxial driver from B&C Speakers, a 5.25” woofer and 1.4" compression driver combo specifically built primarily for sound reinforcement applications. This driver's cooling is exclusively provided by the motor mass, a substantial neodymium ring magnet that powers both HF and LF units. No other vents are required for the 300W power rating given by B&C Speakers to the 5CXN44, which is impressive. This article was originally published in Voice Coil, August 2021.

This Test Bench characterizes the Beyma 12LEX1300Nd 12" driver from Beyma's new LEX Series. This latest design features a FEA-optimized neodymium magnet structure and 4" voice coil, and is targeted at two- and three-way PA speakers, or band-pass subwoofer designs. The entire woofer is optimized with a substantial set of features for very high-performance, including the company's unique Maltcross forced convention cooling system. This article was originally published in Voice Coil, July 2021.