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Industry & Product News
Dolby Laboratories Introduces Platform for Developers
Dolby Laboratories announced, an API platform that gives developers access to APIs designed to improve the quality of the media and communications within their applications. According to Dolby, the platform offers tools to enhance every interaction and quality of content in new apps and services. The interactivity APIs focus on real-time voice and video collaboration, and the Media Processing APIs focus on audio/video content enhancement and analysis .    Read More  

Apple Launches Logic Pro X 10.5 Software with New Creative Tools for Musicians and Producers
Apple launched a major update to its music production software Logic Pro X, adding a professional version of Live Loops, a completely redesigned sampling workflow, and new beat-making tools (drum machines for the 21st century). Increasingly, the software is adding more and more creative features, making Logic Pro X 10.5 a massive release for all musicians, including those producing electronic music. Underneath it all, there is a powerful DAW solution .    Read More

PureAudioProject Announces New Duet15 Prelude Modular Open Baffle Speakers
PureAudioProject is a different kind of high-end speaker company taking a modular, semi-DIY approach to open-baffle loudspeakers. Already with a solid reputation after touring high-end audio shows globally, the company offers four basic modular configurations from which everyone can create their own personalized system. Considering the high-quality results and the choice of components/drivers, PureAudioProject speakers are priced very reasonably. Now, the company has launched the smaller Duet15 Prelude model, offering an introduction to this fascinating concept.    Read More  

JBL Professional Debuts Cinema Expansion Series Line for Small- to Mid-Size Theaters
News from Northridge, confirm that JBL Professional is back to products with the debut of its Cinema Expansion Series sound systems for small to medium-size commercial theaters. The line, which includes JBL 3153 and 4253 three-way screen-channel loudspeakers, 3181F and 4281F subwoofers, and 8102 surrounds, is said to deliver the highest SPLs in its class and be able to cover rooms up to 85 feet (26 m) deep and up to 40 feet (12 m) wide. The company also debuted the two-channel, 1,300 W Crown XLC 21300 amplifier, which supports Cinema Series speakers in a range of system configurations .    Read More  

IK Multimedia Releases Complete ARC System 3 Bundle With MEMS Measurement Microphone for 3D Acoustic Correction
Following the announcement of the ARC 3 System, the third generation of the acoustic correction software that now offers a 3D room analysis algorithm, easier setup and superior results, plus compatibility with more measurement microphones, IK Multimedia confirmed the solution is now available as a complete bundle including a MEMS measurement mic (in addition to a software-only version). The complete pack combines room analysis software, an ultra-accurate measurement microphone and a correction plug-in, all in a simple-to-use package with a step-by-step process .    Read More  

Vanderveen-Trans-SE10 All-Valve Amplifier Kit Now Available!
High-end audio adepts do not just like music. Many of them also like to construct their own valve (tube) amplifiers. For those, Menno van der Veen (electronic design) and Guido Tent (mechanical design and realization) created their newest Valve Amplifier kit: the Vanderveen-Trans-SE10. All parts of the case, the components, and the transformers are of the highest quality. The DIYer only has to combine all these fine components to have a great amplifier .    Read More

Super Hi-Fi Patented AI-Powered Audio Stitching Technology Generates 1 Billion Music Transitions Per Month
Super Hi-Fi, a start-up company from Los Angeles, CA, announced that it's now creating more than 1 billion transitions every month for digital streaming music services, driven by iHeart, Peloton, and the recently launched Sonos Radio. That's 1 billion times its AI technology has created unique, perfect segues from a wide range of audio elements, proving the effectiveness of the company's approach to enriching the dead space between songs or segments .    Read More  

Guest Editorial
David Lindberg
(CEO, DB Enterprises HK Ltd)

Waterproofing of Audio Devices
Unravelling the Technical Solutions
With everyone owning several electronic devices, most of us have experienced sweat damage on our earbuds, drinks spilled on our notebooks, or worse, a phone in the toilet. While the marketing points on the box might claim IPx7, IP68, or sweat proof, from a manufacturing perspective, there are gaps in the different processes to achieve these standards. How does a product get from the obvious problem to these nebulous solutions described on the boxes? What are the solutions or techniques to protect devices from liquid damage? Further, what are the strengths and weaknesses of each solution?

Going out in the elements, our devices are exposed to a plethora of conditions from the steam in bathroom to cooking liquids such as oil, soda, and alcohol in the kitchen and from our bodies where our body perspiration is quite corrosive. The variety of elements that can cause damage to our expensive electronic accessories is quite vast. Further, the variety of solutions that can be used to protect devices from the inside and out are also extensive. All these solutions adhere to the ingress protection scale or "IP" for short in regards to water and dust protection. There are other tests such as salt mist and sweat testing with artificial sweat, but there is no standardized scale to represent the protection levels in this space. For example, one company might mark their box sweat proof with a 48 hour salt mist test and another brand with the same box marking might require submersion in an artificial sweat solution. That said, the methodologies to pass these tests or protect the devices can be divided between mechanical and coatings. The mechanical can be subdivided into barriers and gaskets, while we can partition coatings into conformal and ultra-thin.

This photo shows the thickness and the lack of 3D coverage of the PCBA.

For the mechanical approach, there are gaskets and barriers. For gaskets, there are issues with the durability of the material used. As well, gaskets require precise tooling and good quality material to maintain durable seals. For barrier protections (e.g., plastic housings), the quality of the plastic resin as well as the accuracy of the tooling are factors. Some materials (e.g., nylon, ABS, and PVA) have affinity to absorb moisture. The time between molding and ultrasonic welding increases the likelihood of pores/bubbles developing from trapped moisture during the ultra-sonic welding process. In most audio manufacturing operations, the plastics sub-supplier factories are operating in South China's humidity and they do not vacuum pack your plastics after molding. Therefore, they absorb moisture, and ultimately, there are deformities and/or imperfections by the time they arrive for the ultra-sonic welds in final assembly. These gaps, or gaps from inaccurate tooling, will overtime allow liquids into your devices, which leads to failures.

A classic conformal coating is potting where electronics are literally submerged or sprayed/sputtered with a chemistry. The solutions include materials (e.g., urethane, silicone, acrylic, etc.). They are relatively thick in micrometers and effective for moisture protection, but they prevent heat exchange and the method is not re-workable. These techniques are popular in low-tech (e.g., refrigerators and other white good appliances). Also, they are popular in military and industrial applications. Relative to acoustic applications, these solutions are not feasible for transducers or microphones as they add far too much mass to the diaphragm material.

For ultrathin coatings, there are physical vapor deposition techniques using vacuum plasma to deposit chemistry in a machine or plasma enhanced vapor chemical deposition (PEVCD) for short. These coatings have two subsets based on the applied chemistry: Fluoro and Parylene.
The HZO PRO750 machine is the largest coating chamber in the industry at 1 m3, for repeatable, scalable, and efficient mass production throughput for protecting microelectronics.

First are the Fluorocarbon-based solutions applied with PEVCD, these are truly nano-scaled coatings in the 200 to 300 nano-meter range. These coatings are capable of IPx2-4 maybe IPx5 protection and they can be delivered by brands such as P2i (UK) and FavoRed (CN). The process is typically 45 minutes to an hour in length. There are advances that claim IPx7, but then the process time jumps to 4-5 hours. Some of the benefits with PEVCD are that the process can include PCBA cleaning for solder flux or other contaminant removal, and there is no curing needed post-coating. A major weakness is the batch processing in a chamber, which creates bottlenecks in production. Another major risk is with Lithium Polymer or gel pack batteries. The thin membrane structure of these battery cells will expand and contract during vacuum processing, which can lead to shorts in the batteries. Some weaknesses in acoustic applications include microspeakers and MEMS microphones that are still subject to masking. Further, low voltage data connectors require masking even with 300 nm coatings using PEVCD.

The second category of (slightly) thicker coatings deposited with PEVCD is called parylene. Companies such as Hz0 (US) and SCS (US) offer these solutions. They offer greater protection up to IP68. Their coatings are very good at protection with a still relatively thin profile 3 to 25 µm. They are used a lot in military and some premium consumer electronics applications. The major drawback is the cycle time multiplied by the expensive equipment required. The process cycle time ranges from 3-6 hours and the chambers are 1 m 3 (35 ft 3 ) at the largest and the equipment ranges from $250-$500K USD. Therefore, the process becomes prohibitive in high-volume production. Further, all connectors, contacts, and acoustic components typically need to be masked. 

Finally, there is now a wet chemistry solution from NanoflowX with headquarters in Los Angeles, CA, that is an ultrathin wet chemistry capable of protection up to IP68. Their custom chemistry took 5 years to develop but has tested with winning results against market leaders such as Dow and 3M. With a thickness profile as thin as 1 µm, NanoflowX can be deposited with dip, spray or even a stepper for higher accuracy. Furthermore, the entire process lasts just 5 to 15 minutes. The process is re-workable and very little masking is required. Next, there is no major barrier to entry with equipment costs so the solution is very scalable in production. This is incredibly useful for brands using multiple contract manufacturers. Specific to acoustic products, there is still a little masking requirement on microspeakers and MEMS microphones. Also, low-voltage connectors (e.g., data pins) require masking.

Advantages of the NanoflowX wet chemistry solution.

In summary, there really is no utopian solution to liquid ingress protection but through a combination of mechanical design and coatings, there is a solution to be had. Planning from the beginning of the product development with a clear target in mind for protection is highly recommended.
From The Vault
Distortion Meter and Audio Interconnect Tester
By  Ed Simon
In this article for audioXpress, Ed Simon writes: 
"There seems to be controversy over what testing means in audio. Measuring a difference does not mean you can hear it. On the other hand, if my ears tell me there is a difference between two audio chains and I cannot measure it that does not mean it is not there. Probably, I'm just using the wrong method to determine audio differences. I could measure frequency response, distortion, or other parameters to find the difference. Even if all the measurements were exactly the same, but my ears told me there was a difference, then it would be a question as to where my measurements failed or whether there was something else that should be measured." And after trying to measure all sorts of things to compare which ones sounded fine - or not - Simon decided the next step would be to build a dedicated more sensitive measurement. This article was originally published in audioXpress, November 2009 .    Read the Full Article Now Available Here

Speakers - Parts Is Parts
High-Polymer Film: The Lost Speaker Technology (Part 1)
By  Mike Klasco and Steve Tatarunis
This article explores Polyvinylidene Fluoride Film (PVDF), a piezoelectric polymer used in various transducers for headphones, microphones and loudspeakers. It seems that the audio engineering community at large is either not familiar with PVDF film or misunderstands PVDF piezoelectric film technology. Hopefully, this article will serve as an introduction (or reintroduction) to the technology. This article was originally published in audioXpress April 2013 .    Read the Full Article Now Available Here
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