audioXpress September 2019 Speaker Focus Edition Now Available

August 8 2019, 11:00

The September edition of audioXpress is our always popular Speaker Builder - Speaker Focus edition. Once again, audioXpress focuses on loudspeaker building, design, and testing and for this issue we have combined two great DIY articles with a review of the PureAudioProject Trio15 Heil AMT speaker system. Ward Maas reports from the High End 2019 show in Munich, Jan Didden met with Purifi Audio's Bruno Putzeys and Lars Risbo and comments on the company's research, and much more.

This edition features great speaker DIY projects that are certain to inspire. First, Dan Neubecker proves you can design and build a top notch speaker in your garage with The Echelons, a three-way system using a 12” TC Sounds TC1000 subwoofer, a Bohlender Graebener (BG) Neo10 planar midrange, and a Transducer Lab N26C-A tweeter. A prime demonstration of what is possible when you are passionate about both audio and woodworking. "DIY speaker building can be a compelling adventure, one that consumes much of your free time, but also brings ample rewards that include years of enjoyment and the satisfaction of having created something yourself," he states.

Next up, our frequent contributor, George Ntanavaras explains everything about the design and construction of the AXL dipole loudspeaker, an open baffle, four-way, active design consisting of five drivers from SEAS, Wavecor, and Ciare. His creation, on which he details the design, the construction, and the measurements until the results met his expectations, was dedicated to one of his longtime role models, Siegfried Linkwitz.

There's also a great speaker review, where Oliver Masciarotte and Kent Peterson (of Warkwyn) listen, measure, and listen again to the PureAudioProject Trio15 Heil AMT speaker system. This is a fascinating modular system, in this case is designed using an ESS 6" Air Motion Transformer (AMT) and two purposely designed Eminence 15" drivers, specifically optimized for use in open-baffle applications.

And involving lots of news about loudspeakers - and related technologies - Ward Maas shares his experience at the High End 2019 show in Munich. This year there was lots to see, with 551 exhibitors representing more than 2,000 different brands from 42 countries, and a lot of events also happening outside the main event building, including the concurrent Hifideluxe show. Maas reports on companies such as Purifi Audio, a demonstration of the Theoretica Applied Physics BACCH-SP system from professor Edgar Choueiri, AKM, ELAC, Fink, Focal, Naim, Pro-Ject, Warwick Acoustics, and many more companies.

And while the High End show report mentions Purifi Audio - the company that introduced its new amplifier and loudspeaker technologies in Munich, during that week - in this edition, audioXpress' Technical Editor Jan Didden also met with Bruno Putzeys and Lars Risbo, who recently founded the new Danish company that the entire audio industry is talking about. The Netherlands Audio Engineering Society (AES) section invited the duo for a technical update on their plans, and they gracefully agreed to a presentation on June 13 at the Royal Conservatory of Music in The Hague, which Jan Didden attended and reports. The article also features a side note on the company's business strategy and test and measurement approach, part of a larger interview that is now available on the audioXpress website.

In the second part of his R&D article, Norman Varney writes about "The Basic Principles of Unwanted Vibrations" and what his research found to be effective ways to counteract those effects. The article details the evaluation process and extensive measurements that lead to the creation of various products that AV RoomService provides when helping clients with their acoustic problems.

Finally, in this month's Hollow-State Electronics column, Richard Honeycutt discusses "Listening to Modeled Amp Designs Using LTspice" and how this useful software tool developed by semiconductor manufacturer Linear Technology, now part of Analog Devices, has changed the way audio designers achieve the sound they want and how it saves time, eliminating the need to solder or desolder components.

All this and much more, is now available online, and on its way to those who subscribe to the print edition.

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