L-Acoustics Announces Expanding Universe of Manufacturer Partnerships for L-ISA
L-Acoustics continues its campaign to change the live sound industry with its new approach to multi-source immersive sound reinforcement systems, since it launched its L-ISA technology in 2017. Because L-ISA demands a complete multi-layer sound design solution, the company has announced new partnerships with Avid, Blacktrax, DiGiCo, and KLANG:technologies. L-Acoustics will promote L-ISA demonstrations at Prolight+Sound 2018 with these companiesRead More

Powersoft Introduces New M-Force Design at 2018 Prolight+Sound
With virtually every professional audio manufacturer in the world considering or already shipping subwoofer solutions based on Powersoft's revolutionary M-Force linear motor technology, introduced to the market in 2013, the Italian company will now demonstrate a new generation M-Force at Prolight+Sound 2018, with easier implementation, better thermal dissipation, improved magnetic spring action, and high voltage and current connectors.   Read More

"Road to ATSC 3.0" Exhibit in the Grand Lobby of NAB 2018
With the global media and entertainment industries preparing to descend on the Las Vegas Convention Center for the annual NAB Show (April 7-12, 2018), the Advanced Television Systems Committee announced that more than 40 exhibitors will be showcasing some type of ATSC 3.0 product or service, an indication of the arrival of the new broadcast standard designed to seamlessly meld over-the-air with over-the-top content.    Read More

Celestion Launches the CDX14-3040 Neodymium Magnet Compression Driver
At this year's Prolight+Sound (Hall 3.1, Stand B40), Celestion, one of the world's leading suppliers of professional loudspeakers and compression drivers for sound reinforcement applications, is announcing the launch of the CDX14-3040 neodymium magnet compression driver. This new model utilizes a single-piece pure titanium diaphragm and surround-together with a compact lightweight magnet assembly - to deliver a superior high-frequency performance.   Read More

New Low-Frequency Drivers from Lavoce for Prolight+Sound 2018 
Lavoce Italiana continues to unveil the new drivers that it will be launching at Prolight+Sound 2018 (Frankfurt, April 10-13). The transducer company will be showing the new MAN062.00 high-power 6.5" neodymium midrange; a new 12" model, the WAF123.02 with a ferrite magnet purposely designed for mid-band applications; and the new and powerful 21" subwoofer, the SAF214.50, able to offer super high excursion using a 4.5" CCAW sandwiched voice coil and a ferrite motor.   Read More

OPPO Digital Announces Decision to Gradually Stop Manufacturing New Products
It could well have been an April's Fool story, but unfortunately it was released on April 2nd... In a message of farewell, OPPO Digital has confirmed it will gradually stop manufacturing new products, causing a shockwave among home theater and audio enthusiasts worldwide. A decision which is hard to understand given the success of the brand's range of Blu-ray Disc players, planar magnetic headphones, and the recent entry in the wireless speaker segment. Meanwhile, OPPO Digital confirmed it is open to proposals regarding the IP related to its product design.   Read More

Earthquake Sound Introduces Hum Kleaner - The Hum Problem Solver
Earthquake Sound Corp. introduced the Hum Kleaner, an active converter that provides two channels of unbalanced-to-balanced and balanced-to-unbalanced level conversion in a resilient, compact, and portable unit. Balanced lines offer increased immunity to external electrical noise such as hum. Since a balanced system minimizes induced noise, it is the preferred method of audio connections, especially when long lengths of cables are used.   Read More

Deane Jensen Designed 990 Discrete Op-Amp Inducted to The NAMM Hall of Fame
At the 33rd Annual NAMM Technical Excellence and Creativity Awards (TEC Awards), eight products and technologies inspired by a series of global sound pioneers found their place in audio history when they were inducted into NAMM's prestigious TECnology Hall of Fame. During NAMM 2018, the NAMM Museum of Making Music hosted a special Hall of Fame induction ceremony to honor the Deane Jensen designed 990 Discrete Op-Amp that redefined the op-amp market in 1979.   Read More


Guest Editorial

AKG New Upscale In-Ear Reference Headphones

Click to see the AKG N5005 YouTube presentation video.
On March 27, I attended an introduction to the new AKG N5005 reference class in-ear headphones taking place in London, UK. These new headphones, first unveiled at CES 2018, use the Harman IE Target Curve, as discussed in the recent Audio Engineering Society papers by authors Sean Olive, Todd Welti, and Omid Khonsaripour ( part 1 dedicated to on-ear headphones and part 2 , which measures in-ear headphones) from Harman International.
A small group of journalists was invited for this rather special event, planned essentially for the lifestyle press. Of course, the AKG N5005 will get attention from all the more marketing-oriented press, but they are not exactly the audience for the stage set by Dr. Sean E. Olive. Simply because his presentation, or better yet his lecture, was about the science behind the development of the AKG N5005, which inspired me to write this brief report for the more technical-minded audience of The Audio Voice, even though I was there on assignment from Dutch magazine HVT, for which I write regularly.
The first thing Olive stated was that there was hardly a correlation between user preference in terms of the frequency response of a headphone (in-ear, on-ear, or around ear) and its price. The graph with the results of the research conducted by Harman, based on a large selection of headphones, was very clear about that. Worse, the correlation between perceived quality and price, based on listening tests, was definitely not good. In the past, Olive and his team defined the so called "Harman target curve," a frequency response curve that fits best with perceived quality. For further study on this subject no less than 283 headphones were compared to this Harman curve. 
Listening tests were done with listening groups, and a large controlled variety of listeners (trained, untrained, sex, age, countries, culture, etc.). Besides the variety in the listeners' sampling, careful attention was given to perfect fitting, as leakage can greatly influence the results. After a lot of statistical work on all the collected data, a model emerged in which accurate, statistically relevant predictions could be made with respect to frequency response and perceived quality. The results of this study were applied to the development of the AKG N5005.

Sean Olive during his presentation, detailing the extensive Harman research on user preferences and target frequency response curves for in-ear headphones.

The N5005 is a customizable reference class five-driver configuration in-ear headphone. That means everything is special with this product. From the high-gloss piano black ceramic, chosen for its strength, durability, color depth, and scratch resistance, to the choice of drivers, with a 9.2 mm paper membrane driver selected for the lower frequencies, complemented with two mid-range- and two high-range balanced armature drivers, providing a 10 Hz to 40 kHz frequency range.
From the Harman research, it was clear that younger people prefer a bit more bass. Therefore, the N5005 comes with four filters, which enable the customization of the frequency curve. The factory response corresponds to the reference curve. The remaining four filters are described as Bass Boost, Reference Sound, Semi-High Boost, and High Boost.
Another issue is the proper fit of in-ear headphones. Not only is this a comfort issue, but also leakage will alter the perceived quality, making the fit extremely important. The N5005 comes with four ear-tips in different sizes and three SpinFit ear-tips also in different sizes, ensuring a perfect fit for different usage scenarios. 

Designed to reproduce high-resolution audio sources, the N5005 uses a hybrid of one dynamic and quad BA drivers to create an extraordinary five-way in-ear experience.

Unlike the previous flagship AKG K3003, the N5005 comes with high-quality detachable twist cables. The detachable cables make replacement easy if a cable gets damaged and enables cables to be easily adaptable to the user's preference. The same MMCX cable connection is used throughout. The two twisted wire cables include a balanced 2.5 mm version and a 3.5 mm Android and iOS cable with control unit. With this unit, which incorporates a microphone and controls for music and speech, there is also a switch to choose between Android and iOS. Another important added feature is a Bluetooth 4.1 dongle with aptX and AAC audio support, which features a three-button universal remote mic. The AKG N5005 delivers up to eight hours of battery life in wireless mode.
Also handy is the included two pin flight adapter and a cleaning tool, provided to keep the N5005 in optimal condition. Each individually serial numbered headphone comes at a price - $999.95. According to Harman, the N5005 is targeted at users who want the best in every aspect and who will be able to appreciate the product quality.
Having heard from Olive - and from his team's extensive research - that the N5005 closely follows the Harman target frequency response curve - even if bundled with filters that enhance specific frequencies according to personal taste - this will be a product that will be placed in the extreme upper corner of the Price versus Preferred Sound Quality chart. There's no doubt that the tools provided by this research paved the path for a sublime example of in-ear headphones, and maybe also a new reference for the industry.


From The Vault
Selecting a Power Tube
By Richard Honeycutt
In this article, Richard Honeycutt provides a brief description of the main tube types used in audio applications, from triodes to tetrodes and pentodes, describing their uses, features and potential benefits. If you are looking for a quick reference about tubes that have been used in audio amplification, this article is a great start. This article was originally published in audioXpress, May 2013 as part of the Hollow-State Electronics monthly column by Richard Honeycutt.   Read the Full Article Now Available Here

Voice  Coil Test Bench
Peerless by Tymphany 
Full-Range 5" PLS-65F25AL01-08
By Vance Dickason
The 2" to 2.5" diameter full-range drivers are unquestionably one of the most used transducers in consumer electronics. They are finding broad applications in soundbars, pedestal soundbars (soundbars that double as TV stands), docking stations (these are starting to go away), desktop speakers (e.g., the Sonos products), and portable Bluetooth speakers (e.g., Jambox, Beats, Samsung, Bose, and a million others). Following the previous review of the Peerless by Tymphany 2-inch PLS-50N25AL01-08 neodymium motor full range, I reviewed the 2.5" PLS-65F25AL01-08 ferrite motor full-range model. This 2.5" 8 Ω full-range member of the PLS family, the Peerless PLS-65F25AL01-08, has some differences from the other 2" PLS-50N25AL01-08 model I previously reviewed. Unlike the PLS-50N plastic frame, the PLS-65F is built on a proprietary stamped steel frame that is fully vented below the spider mounting shelf with four 24 mm × 4 mm cutouts for enhanced cooling. Additional cooling is provided by a series of nine 1.5 mm diameter vent holes in the 25.73 mm aluminum (ASV) former just below the neck joint. The cone assembly consists of a black anodized aluminum cone, with a 27 mm diameter aluminum dust cap (directly coupled to the voice coil former), and suspended with a NBR surround and a flat cloth spider (damper). Motive force for the cone assembly is supplied by a 60 mm diameter 14 mm thick ferrite motor that incorporates a copper cap shorting ring (Faraday shield) and a shaped T-yoke. Tinsel leads connect on one side of the cone to a pair of solderable terminals. This article was originally published in Voice Coil, November 2017.   Read the Full Article Online

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