THOR: A D’Appolito Transmission Line

One of the most important speaker building projects published by audioXpress, THOR was designed by Joseph (Joe) D'Appolito, who is world-renowned for his pioneering work on MTM-based (mid-tweeter-mid) loudspeaker configurations. The original THOR transmission-line design was published in May 2002. For this online publication, audioXpress kept the original article unchanged, which has since been updated with availability of the original Madisound/SEAS kit and the publication of a complete kit project on the SEAS website. Read the complete article here.

Loudspeaker design is not a trivial exercise, and as a result, high-performance acoustic simulation software is essential to get accurate predictions that help an engineer develop superior products. Demand for simulations at early design stages are increasing because cost and timing constraints make it impossible to prototype and test every design idea and much can be learned from simulation results, which cannot be obtained in the test chamber. Actran, MSC Software Company’s acoustic simulation solution, based on Finite Element Analysis (FEA) technology, provides predictive simulation capabilities to assess the vibro-acoustic performance of audio devices, which include speakers and microphones.

Recently I attended the excellent, The Home Entertainment (T.H.E.) Show in Newport, CA. Celebrating its 6th anniversary, and still mourning the tragic loss of its president and founder, Richard Beers, T.H.E. Show Newport exceeded its own 2015 attendance figures, with more than 10,000 attendees. I left with excellent memories of a wonderful organization, a very pleasant location (Irvine), and the motivation to return. Some excellent systems left me with enduring impressions that I thought fit to share in this space.

Creators of high-performance professional loudspeaker technologies, Fulcrum Acoustic have introduced the FLS115 Subcardioid Subwoofer. A powerful complement to its companion FL283 Subcardioid Line Array, the FLS115 is ideal for the most demanding venues, including performing arts centers, houses of worship, sporting facilities, and nightclubs.

In this testimony, British company Flare Audio explains their unique approach to loudspeaker design based on the theory of Waveform Integrity, combining driver alignment and a patented enclosure structure and porting technology. All Flare’s sound reinforcement solutions use FaitalPRO drivers.

Free Field Technologies (FFT), an MSC Software Company, announced the release of Actran 16. The new release provides new audio and electroacoustic capabilities; acoustic propagation in huge domains and at high frequencies; new aeroacoustic modeling capabilities for fast virtual testing; and co-simulation with other MSC Software tools for multi-discipline analyses. The new release also introduces performance enhancements, including on graphical user interface and its meshing tool.

The pioneer and market leader in whole-home audio connected solutions announced the all-new flagship Sonos PLAY:5 smart speaker and a new speaker-tuning software called Trueplay. The announcements signal a new series of innovations in hardware and software from Sonos with which the company intends to respond to increasing competition, while leveraging the latest technology advancements.

Loudspeaker and audio systems manufacturer MISCO has acquired Warkwyn Associates, an independent acoustic design, measurement, and testing lab. MISCO president Dan Digre says that Warkwyn will continue to provide its same high level of services for current Warkwyn customers. Warkwyn has relocated from Pakenham, Ontario to MISCO’s home base of Minneapolis, Minnesota.

Some speaker designers approach their creations based purely on self-acquired knowledge and research, deliberately trying to distance themselves from existing trends and debates. Others, base their work on team efforts, industry partnerships, and sometimes market-oriented options. These are the people who I’ve started to categorize as the Wizards and the Cooks.

The application of acoustic resistance as a design element in the optimization of transducers and enclosures has been given short shrift in audio engineering. Controlling the acoustic resistance of the driver radiation is a quality factor that is overlooked in most loudspeaker predictive modeling software. This article explores applications of acoustic resistance for audio.