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VK-X aluminum

Aluminum and anodizing


Hello everyone,


1) Made-to-order option 2 selected: the aluminum colors


This is Paul. As promised, I am coming back today to present the second article in a series dedicated to our made-to-order headphones. We first introduced our leather, how it’s made, and where it comes from. Today, we are going to talk about the aluminum and, more specifically, about its anodizing

I will take a moment to remind you of the most recent poll of our options for personalization:


Link to survey: http://journal.aedle.net/2018/04/25/bespoke-survey/


2) The Anodization of Aluminum and its alloys


The second critical piece of our headphones, the aluminum cup, is a result of a process that is known as anodization or anodic oxidation. Aluminum is a lightweight metal, highly malleable, and resistant to corrosion. However, in its raw state, it is soft and has impurities. Anodizing gives the part concerned protection against wear and corrosion due to oxidation by carrying out the latter in a controlled environment (aluminum oxidizes spontaneously upon contact with air). The oxide layer that covers aluminum is called alumina; it is a very hard, uniform, transparent and insulating body.

To anodize aluminum, one proceeds in the same way as for the electrolysis of water (a phenomenon caused by the passage of an electric current in the water, cf diagram below). There are, however, some differences: the workpiece is the anode (negative potential in yellow below) and an ionic solution (sulfuric acid most of the time) is used, pure water being non-conductive. Due to the electric current, the water molecules are decomposed into hydrogen and oxygen; the surface of the workpiece is therefore directly exposed to the oxygen formed by the decomposition of the water, resulting in the formation of alumina.



The electrolytic treatment produces a much thicker layer of alumina than during the natural oxidation process (1). The structure of the aluminum is porous and allows the electrolyte to conduct the current to the metal. Once the anodizing is carried out, we go to the staining step (2) and finally to the sealing of the pores present in the alumina in order to reinforce its resistance (3). This last step is done in boiling water or steam in general, but can also be done cold.



3) aëdle aluminum


To obtain a perfect rendering, we chose the T-6063 aluminum, low alloyed with magnesium and silica, frequently used in aviation and architecture. It is ideal for machining complex shapes and its clean, smooth surface is particularly suitable for anodizing. In order to achieve the desired result with regard to our “cups”, it is necessary for us to perform aluminum machining in the mass, piece by piece.




4) Choice of available aluminum colors for the VK-X


I invite you to read this other article dedicated to the choices we made in terms of aluminum colors for the VK-X:



All this was a bit technical so please do not hesitate to ask questions and we will be happy to answer!



Part 1 – Why Bluetooth 4.2 over 5.0?

Hi everyone,

We have received an overwhelming number of responses concerning the VK-X and I would like to personally thank you for your support and commitment to our project.

Today I am going to the take the time to respond to a question that has come in a number of emails.


Will the VK-X have Bluetooth 5.0?


The answer is NO for several reasons. It will, in fact, be 4.2 and it will indeed have the same efficiency of that of 5.0 Bluetooth (that is to say compatible with Bluetooth 5 devices for audio streaming), but I am going to take the time now to explain why we made this choice.

When the Bluetooth Special Interest Group (SIG) announced the creation of Bluetooth 5.0 in 2016, there was a lot of buzz generated for this seemingly major advance in wireless technology. What is interesting, however, is to see at what point certain parties including media outlets and invested companies have questionably manipulated this information for their benefit.

Here are the ‘ameliorations’ proposed by Bluetooth 5 technology that you see everywhere:

  • Range x4
  • Throughput x2


What we don’t see or what is not often stated is that, firstly, one must choose between the two ameliorations. It is one or the other in relation to the radio chosen by the system integrator (“PHY”). On the other hand, these ameliorations are exclusively for BT LE (Low energy products), which is technology dedicated to the internet of things with a very low energy consumption. The Bluetooth low energy sends small packets of information and isn’t really adapted to continuous music streaming.

Bluetooth Classic is the technology used for audio applications, via a superieur bandwidth (3 Mbps in theoretically 2.1 Mbps actually) and a profile dedicated to audio applications “A2DP” (Advanced Audio Distribution Profile)


In all fairness, to do justice to the BT 5.0, Bluetooth 5 nevertheless sets a very solid foundation for the arrival of a new standard of audio streaming, with reduced energy consumption, to achieve a theoretical bit rate of 2 Mbps, effective around 1.4 Mbps.

Nevertheless, there are several problems to be resolved, via the creation of a new profile (like the profile A2DP used for audio streaming):

  • Recomposition of segmented data packets
  • Management of asynchronous data packets



To resume,


  • Audio streaming via Bluetooth is done via the A2DP profile, managed uniquely by Bluetooth Classic
  • The bandwidth of Classic Bluetooth is higher than the bandwidth of Bluetooth LE (5.0).
  • BT LE 5.0 is a preparation for the future of audio streaming that consumes less energy and yet uses enough bandwidth for high-quality audio streaming



In my next article about this topic, I will develop more. I will explain more about Audio Formats, Codecs and Bits. Please do not hesitate to post your questions: I will be happy to answer!