Low Frequency in Loudspeakers: It’s All About the Bass!

All the speaker design techniques to achieve more bass, challenging Hofmann's Iron Law. The same bass in a smaller enclosure? Deeper or louder bass for the same enclosure back volume? Higher efficiency for a given alignment? A cleaner lower distortion bass? Learn about the companies, products, and technologies that make all this possible. This article was originally published in Voice Coil, November 2023.

This article describes bass and treble tone control circuits where the frequency at which control begins in each band is variable over a 16 to 1 range, making it much more useful for correcting speaker deficiencies or room anomalies. Something that very few manufacturers have offered. This article was originally published in audioXpress, December 2023.

Dutch Pro-Ribbon specialists Alcons Audio have expanded its range of loudspeaker solutions with a new innovative design. The Alcons QB363 mkII is a modular column bass system, designed as a low-frequency extension (LFE) system to the Q-series line-source column systems - such as the versatile QRP20 Pro-Ribbon column array, or the more recent QRP40 point-source column. However, the new compact design can be used as an arrayable LFE system with any Alcons system.

James Croft reviews another patent of a concept ignoring abundant prior art, which apparently wasn’t scrutinized by industry experts - as it should. The patent "Dynamic Acoustic Waveguide," was awarded to William Eugene Wheeler (High Ridge, MO) as inventor and assignee, and describes a “loudspeaker and a method of operation that allow for the production and emphasis of extremely low bass tones.

This review discusses an intriguing speaker design patented by Walter Ka Wai Chu, from Taiwan. The design allows the speaker device to potentially improve the bass performance in the entire low-frequency band instead of being limited to only a few low-frequency points, the inventor claims. While James Croft confesses to being somewhat skeptical of whether, in its current disclosed form, the device will provide a useful advantage, he found the design sufficiently interesting to be analyzed in more detail.

Following the review of the KEF LS50 Meta speakers for audioXpress, this article offers a detailed review of the KC62 compact subwoofer, which combines KEF's force-canceling and Uni-Core technologies in a new approach to allow maximizing bass in a minimum space. Masciarotte did the listening and spoke with Jack Sharkey, Senior Technical Engineer at GP Acoustics, about this fascinating design. The subwoofer was also measured by Peterson at Warkwyn’s facility using the Klippel measurement system.

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.

Vented systems are in chronic overload. This article shows how, by applying low-cost digital signal processors (DSPs) to passive radiators, you can extend bass an octave below what is normally considered practical. At the same time you can increase power handling and maximum output, and squeeze high performance from tiny systems. We all know reflex systems are more efficient and offer deeper bass than sealed systems. However, the vast majority still fall short of their potential by 6 to 12 dB or more. Worse yet, often people don’t realize how vulnerable drivers are to damage. Many abuse woofers without knowing it. Few realize how much more sound output is possible from a DSP Assisted Reflex design.

In this Test Bench, Vance Dickason receives the latest 18NDXL Imperium, a very high power handling 18" low-frequency woofer from British brand Fane. Designed by this revitalized company with a rich history, the 18NDXL Imperium includes uses as a bass driver in multiway systems or as a dedicated woofer in bass reflex or horn loaded designs. The feature set for the 18NDXL is like most high-performance pro sound drivers, rather substantial. This article was originally published in Voice Coil, April 2020.

Celestion made three of their most iconic speaker Impulse Responses – the Vintage 30, G12M Greenback and Celestion Blue – now available in Two Notes format, for use with the company’s critically acclaimed sound emulation hardware Torpedo (Studio, Live, C.A.B), the speaker and miking simulation engine; and Wall of Sound software environment, which is a DAW plug-in version of the company's Torpedo hardware processor, available in rack format and multiple other configurations.