Adam Hall Group Introduces MAUI P900 Portable PA Concept in Collaboration with Porsche Design Studio
With one of the largest booth areas at Prolight+Sound 2017 in Frankfurt, the Adam Hall Group - both a manufacturer and distributor of event technology solutions - captured all the attention at the Frankfurt show, unveiling several new products among its many brands and introduced the new MAUI P900 Concept portable PA system, from its LD Systems brand, designed in collaboration with the legendary Porsche Design Studio. It seams clear Adam Hall is raising the bar for the pro audio industry Read More

Yamaha Introduces New Control Surface for RIVAGE PM10 Digital Mixing System and Significant Updates at Prolight+Sound 2017
At Prolight+Sound 2017, Yamaha Professional is focusing on significant updates to several products, as well as highlighting the benefits of its most recently launched loudspeakers. Most importantly, its flagship RIVAGE PM10 digital mixing system has been expanded with the launch of the new CS-R10-S control surface, which is approximately two-thirds the size of the existing CS-R10 for use in environments with limited space, such as theater FoH mix positions or monitoring side stage.   Read More

JBL Professional New VTX A12 Line Array Introduced at Prolight+Sound 2017
As expected, JBL Professional launched its new VTX A12 Line Array at Prolight+Sound 2017. The new system is an extension of JBL's VTX family, using a new dual 12" line array loudspeaker element, engineered from the ground up to provide best-in-class performance, reliability, and ease of use. The new line array is intended as a completely redesigned solution for mid- to large-size touring productions and high-end fixed installationsRead More

FaitalPro Introduces Three New Woofers at Prolight+Sound 2017
Striving toward perfection, FaitalPro has expanded its professional speaker catalog at Prolight+Sound 2017 in Frankfurt with the introduction of three new woofers. The new 12RS550, the 12PR320, and the 10PR320 models are specifically targeting the competitive and fast paced European pro audio and music instrument (MI) market. In a landscape of great performance and reliability, FaitalPro submits three new woofers in direct response to increasingly demanding requirements.    Read More

Martin Audio Announces Expanded New Product Line Up at Prolight+Sound 2017
At this year's Prolight+Sound Show in Frankfurt, Martin Audio unveiled an ambitious line up of 10 new products across multiple categories including line arrays, stage monitors, and amplifiers. It's as if the British company is creating a completely new catalog, creating new solutions for different market demands, and leveraging its key technologies - including Coaxial Differential Dispersion drivers and the fundamental approach from its successful MLA line arrays on the new Wavefront Precision seriesRead More

Meyer Sound Introduces LINA and 750-LFC to its LEO Family
Meyer Sound's LEO family of linear sound reinforcement systems has been expanded with the addition of the diminutive new LINA compact linear line array loudspeaker and companion 750-LFC compact low-frequency control element. Easily the smallest and lightest in the series, LINA and 750-LFC bring the inherent linearity, low distortion, and exceptional power-to-size ratio of LEO family technology to a wider range of applications and venues.  Read More

Lavoce Italiana Launches SAN214.50 21" Neodymium Magnet Subwoofer at Prolight+Sound 2017
Lavoce Italiana is launching its SAN214.50, a new high power 21" neodymium magnet subwoofer at Prolight+Sound 2017 in Frankfurt (April 4-7). The new large subwoofer features a stylish die-cast aluminum basket, in line with the brand's most recent range of products, and offers an impressive 98.5 dB sensitivity and a Program Power handling capability of 3400 W.   Read More

Zound Industries Selects Frontier Silicon Minuet Platform for Urbanears Connected Speakers
Frontier Silicon announced that its Minuet platform was chosen by Scandinavian audio pioneer, Zound Industries, to power its new range of connected audio speakers with Apple Airplay, Spotify Connect, and Chromecast built-in. The new Urbanears Connected Speakers are truly a reference of what current generation wireless speakers can offer, combining amazing design with a simple and rewarding experience at affordable prices.   Read More


Guest Editorial

Enhancing Headphone Comfort and Performance

OPPO PM-1 high-end headphones
Every headphone has ear cushions and these have a significant impact on acoustic performance and comfort. However, there is a total lack of engineering papers on this and the related topic of headband design. Ear cushions are not just for comfort, as they have a significant effect on frequency response. The chamber formed by the ear cushion, along with the covering skin and internal materials, usually have some response anomaly in the 5 to 10 kHz range. The ear cushion may use sophisticated memory foams or cheaper solutions (e.g., basic polyester and polyether), and sometimes medical gels have been used.
This air mass acoustic inductance formed between the driver diaphragm, the inside diameter of the cushion, and the ear can be tuned by manipulation of the dimensions and materials along with acoustic resistance vents with membranes. The acoustic resistance of the membranes can be non-woven or fine-mesh woven. Some high-end headphones such as the OPPO PM-1 are offered with leather and suede outer ear cushion skins, which impact comfort and response - often this can be a personal preference trade-off.
BASF Superabsorber Luquafleece material is used for headphone cushions. A single square meter of Luquafleece, only a few millimeters thick when dry, can absorb up to 26 liters of water.
The cushions also have a strong influence on the upper midrange and on the bass response, especially with over-the-ear designs that contact the head around the ear (circumaural). If there is too tight a seal to the ear/head then bass will be too restricted. Yet if a vent hole is used, then undamped response will result. The MKS Rayls' acoustic resistance of the vent membrane is a powerful tuning tool to tweak these phenomena.
A totally unrelated but important aspect is the low-frequency passive attenuation of ear cushions. Again, a tightly clamped headphone can have excellent passive sound isolation (attenuation of external sounds) but be unpleasantly uncomfortable. Not much sense in an otherwise high-performance noise canceling headphone if the user has to take it off after a few hours into the flight!
Even the way the cable attaches to the headphones on loosely clamped headphones can have a significant impact on bass response between channels. In headphones where the cable attaches to only one earcup can result in that side being torqued away from a tight fit and reduce bass coupling to the listener's ear. When the cable is split-attached to both earcups and connected in a "y," this approach tends to have less impact on the response between channels.
When you put on a closed-back headphone, there is significant attenuation of outside sound - about 1000 Hz, usually over 10 dB with on-the-ear (supra-aural) - and about 15 dB for most over-the-ear types.  This noise blocking is known as the "passive mask" and is caused by both the cushions and the earcups. Below about 1 kHz, attenuation progressively drops to 5 dB or even less at 100 Hz. Much of this leakage is through the ear cushions. This is why active noise canceling (ANC) makes sense, as it is most effective from 1 kHz downward blocking where passive attenuation is marginal. But ANC adds expense, as well as battery-life issues.
Coming later this year is a new class of ear cushion filling material that dramatically blocks external low-frequency sounds from passing through the cushion and will be explored in depth in an upcoming audioXpress article focusing on headphone ear cushions.

This is BASF's Luquafleece super absorption material, shown under a microscope.
The earphone cushion and the headband cushion dominate the wearer's tactile impression of a headphone. Comfort is a combination of the weight of the headphone, the clamping force, the area where the cushions and headband contact the head, the ability to adjust the headphone to the user's head, and all these factors are balanced and considered - at least by the more experienced headphone designers.
Perhaps the most important aspect that remains unaddressed is that the brain runs hot and this heat is released at least partially through the ear canals. When this heat path is blocked with a headphone, the temperature of the ear canal rises over time causing the "wax" (cerumen) formed in the outer ear canal to break down in viscosity. Blocked ear canals can become sweaty, itchy, and uncomfortable.
To combat heat and moisture in headphone materials science, BASF is offering Luquafleece, a "no-sweat" super absorbent material. By absorbing moisture, the heat is also absorbed. When the headphones are removed, the moisture (and heat) is quickly released. Luquafleece has fast absorption and de-absorption times and, when used specifically for headphones, the material is treated with an anti-microbial - so it does not retain odors. Luquafleece is placed on the inside of the ear cushion donut and an open-weave breathable fabric is used (on the inside of the donut).

With many of the leading headphone manufacturers currently experimenting with Luquafleece and other new materials, expect many brands to feature more comfortable headphones for their next-generation models.

In its Saatifil Acoustex range, SAATI has developed mesh solutions to solve most, if not all, the challenges for headset audio design.
Fresh From The Bench
Audio Precision's APx1701 Transducer Interface
By Stuart Yaniger
As a long-standing tradition and one of its most popular special focus editions, audioXpress March 2017 includes a wide assortment of Test and Measurement articles, both of great interest to DIY enthusiasts and industry professionals. As one of our cover highlights for this special edition, audioXpress featured a thorough review by Stuart Yaniger of Audio Precision's new APx1701 Transducer Interface. This compact solution, when combined with an APx500-series analyzer, creates a test center suitable for measuring speakers, headphones, and microphones, as well as electronics. As Yaniger dsicovers, the combination of the APx1701, an APx515, and APx500 software, provides an extremely comprehensive and convenient multi-functional measurement test center, of great value and precision. In his introduction of the APx515/APx1701 review, Yaniger writes: "Without question, the traditional gold standard in audio test gear has come from Audio Precision, based in Beaverton, OR. Its test gear has been the go-to choice for the past 30 years, and any serious engineer has made extensive use of the equipment for characterizing the electronics end of the audio production and reproduction chains." In his review, Yaniger details all the possibilities of the APx515/APx1701 combination as a multi-functional measurement test center and explains why the integration saved him one of the most important assets in life: time. This article was originally published in audioXpress, March 2017.   Read the Full Article Now Available Here

Voice  Coil Test Bench
Two Beryllium Tweeters from Scan-Speak - D3004/604010 and the D3004/604000 
By Vance Dickason
In this edition of Voice Coil's Test Bench we review two beryllium dome tweeters from Scan-Speak. These two new beryllium diaphragm neodymium motor tweeters, the D3004/604010 and the D3004/604000, basically share the same platform, with the major difference being the D3004/604010 has a lower Fs due to the larger rear cavity. Both tweeters use a Materion 26-mm 99% pure beryllium dome, an underhung two-layer copper wound voice coil with 0.2 mm Xmax, a neodymium ring magnet in conjunction with Scan-Speak's patented symmetrical driver SD-2 motor system (the SD-2 includes copper shorting rings), a non-resonant aluminum rear cavity, a wide coated cloth surround, and a sonically transparent metal protective grill with a 9-mm diameter diffuser built into the structure. The protective grill keeps the dome from being damaged and is a necessary safety precaution when using beryllium. While beryllium is safe in its molded form, if shattered, it's a fairly nasty contaminate that also necessitates careful disposal at the end of its product cycle. This article was originally published in Voice Coil, May 2016.   Read the Full Article Online

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