Mis à jour le 20 October 2020.
We were lucky enough to be invited by Audioquest to visit its factory and logistics center in the city of Roosendaal in the Netherlands. The opportunity to take a look behind the scenes at the manufacturing process for the brand’s different cables. We also enjoyed listening sessions inside Audioquest’s facilities during which we were able to compare the advantages of the brand’s different ranges of cables.
Audioquest factory tour: a bit of history
Audioquest’s story began in 1978 when Bill Low, a true audio enthusiast, made his first cables. Manager of a small hi-fi store overlooking a Californian beach, he noticed that the quality of audio cables wasn’t very good and that they significantly deteriorated the transmission of the audio signal. Consequently, he decided to create his own hi-fi cables, paying particular attention to the materials, insulators and assembly methods used in order to allow his customers to get the best performance out of their hi-fi system. The cables were such a big success that Bill Low decided to found Audioquest in 1980 and focus entirely on cable design.
Audioquest’s research focused on insulation, as well as the structure and design of the conductors. In 1985, Audioquest became the first American audio cable company to improve signal transmission. An innovation that led the brand to be acclaimed by the international press and allowed it to forge itself an excellent reputation in the world of high fidelity.
In the late 80s, Audioquest expanded its catalog and applied its expertise to video cables. As a result, the first Audioquest composite cable was created, a model that used high-purity copper conductors and optimized geometry to reduce loss and interference in the video stream. Audioquest is still present in this field today with a wide range of HDMI cables. Made of premium materials and equipped with the brand’s best technologies, Audioquest’s HDMI cables are designed so that you can fully enjoy your A/V system.
Much more than just a cable specialist, in recent years Audioquest has also become a reference in the USB DAC market. Everything began in 2012 when the Californian manufacturer launched the Audioquest DragonFly Black, a high-performance DAC and headphone amplifier disguised as a USB flash drive. It handles audio streams up to 24-bit/96kHz and can be used with a Windows or Mac computer, as well as Android and iOS smartphones and tablets.
The DragonFly Black became a true reference and is still included in the brand’s catalog. It was updated in 2016 with the Audioquest Dragonfly Red, which featured a new ESS Sabre ES9016K2M DAC, then by the Audioquest DragonFly Cobalt in 2019. The latter is the flagship of the DragonFly USB audio DAC range and incorporates an ESS Sabre ES9038Q2M chip, a portable version of the most powerful converter from the American manufacturer ESS Technology. Compatible with MQA and 24-bit/96kHz streams, this USB DAC also benefits from improved power supply filtering that limits external interference and uses less power, preserving the battery of the associated mobile device.
Audioquest factory tour: cable theory
Before discovering the manufacturing process of Audioquest cables, we were lucky enough to attend a lecture on cable theory and the philosophy of the Californian brand given by Bryan Long, Vice President of Audioquest. For over 40 years now, each Audioquest cable is made following four fundamental principles: the cable’s structure, geometry, conductors and insulation. How these four elements are selected and balanced is the key to the success of Audioquest cables. To better understand the brand’s approach, here is a detailed description of each element and its role in the transmission of the audio signal.
The structure of the conductors is the first element studied by Audioquest to optimize the audio signal transmission. Most manufacturers use several strands that are twisted and bundled together to form a single conductor. The problem with this design is that there is a lot of interaction between the different strands which can generate distortion. Moreover, with a speaker cable, the high voltage of low frequencies can also generate magnetic disturbance and deteriorate the transmission of high frequencies. To avoid these problems, many Audioquest cables use solid or semi-solid conductors. The interaction between the strands is reduced, which minimizes signal deterioration and provides better performance.
The quality of the copper or silver is another factor that Audioquest takes into consideration to accurately transfer the audio signal. The manufacturer uses three grades of copper in its analog, speaker and power cables, as well as solid silver in its top of the line cables, and silver-plated copper for video and digital cables. Here are the different conductors used by Audioquest and the reasons why the manufacturer uses them in more detail:
LGC or Long Grain Copper is a type of oxygen-free copper optimized by Audioquest. The copper is optimized using a specific casting method that further reduces the oxygen content of the copper. It is important to note that even high-purity oxygen-free copper still contains a very small amount of oxygen that can form copper oxide and generate distortion. By reducing the level of oxygen in this way, LGC conductors ensure a more precise and accurate transmission of the audio signal. In addition, LGC is made from much longer gains of copper. The density is about 300 grains per 30cm for LGC copper, compared to over 1500 gains for classic copper. However, the interaction between two grains results in conductivity contrast as well as distortion. Therefore, the low grain count of Long Grain Copper ensures better performance.
PSC or Perfect Surface Copper is made using a proprietary machining process that consists of drawing and annealing the copper to create an exceptionally soft and smooth surface. The surface of each strand is also extensively polished to make it even smoother. This further reduces the interaction between the strands and ensures a better transmission of the signal traveling over the conductor’s surface. Audioquest also uses PSC+ copper, which benefits from the same machining process, but uses an even higher purity copper.
- Silver-plated copper
Audioquest mainly uses silver-plated copper in its high-end audio and digital cables to optimize the transmission of very high frequencies. These signals, being of such a high frequency, travel almost exclusively on the surface of the conductor. By applying silver plating, it is possible to enjoy performance very close to that of a solid silver cable at a lower price. Some Audioquest subwoofer cables also use silver-plated copper as it helps improve the precision and impact of the lows.
The third element analyzed by Audioquest to preserve the signal during its transmission is cable geometry. The geometry directly influences the connection and interaction between the conductors and, consequently, the signal transmission. For example, a speaker cable with parallel conductors will produce a dull sound and act like an antenna. A speaker cable with a pair of twisted conductors risks producing a veiled and flat sound. One of the solutions adopted by the Californian manufacturer involves using a minimum of four conductors with counter spiral geometry which consists in winding the negative conductors in one direction, then surrounding them by positive conductors that are spiraled in the opposite direction. This geometry limits interaction between the positive and negative conductors, consequently reducing distortion caused by the magnetic fields.
Finally, the last element studied by Audioquest to ensure perfect audio signal transmission is the internal insulation of the cable. The goal here is to keep the cable’s positive and negative conductors apart rather than protecting the signal from external interference. The hardest part is to find a material that provides perfect isolation but doesn’t have an adverse effect on the signal. For this, Audioquest uses a variety of polymer plastics. The more high-range models also benefit from azote-injected foam to create an air gap between the different materials. As air doesn’t have any influence on the signal, the distortion is considerably reduced compared to insulation that is in direct contact with the conductors.
Audioquest cable manufacturing process
Stripping the cables
Today, Audioquest is present in over 65 countries throughout the world. The brand has offices and workshops in California, Hong Kong and the Netherlands. We were invited by the manufacturer to visit the Dutch factory and discover the manufacturing process of its iconic cables. The process begins in California where the copper is smelted by Cardas and inserted into its definitive sheaths. Some of the cables made for the European market arrive in reels at Roosendaal in the Netherlands to be cut to different lengths and assembled. During our tour, we had the opportunity to see the assembly of an Audioquest ThunderBird Zero cable, a high-end model equipped with banana plugs and DBS (Dielectric-Bias System) technology. Done entirely by hand by Audioquest’s workers, each Audioquest ThunderBird Zero cable takes over two hours to make. A very long process that starts with the extraction of the outer sheath and the layers of insulation at both ends of the cable to access the different conductors. This procedure requires surgical precision, as no less than seven layers need to be removed for this particular model.
Once the sheath and layers of insulation have been removed, the different conductive wires are visible. The Audioquest ThunderBird Zero speaker cable has eight solid conductors in PSC+ copper (four positive and four negative), as well as a metallic braid on which the DBS is soldered. The latter delivers a 72 volt current to create an electrostatic field along the cable and polarize the insulating layer to reduce interference during the transmission of the audio signal.
The cable’s eight wires are bundled into two sets of four (four positive and four negative), then about 3 to 4cm of the conductors are stripped. The conductors are then twisted around one another to create a single strand. The non-stripped parts are placed inside a thermoplastic sheath to hold them in place. These are then covered with an insulating layer identical to the outer sheath of cable.
At this stage, the cable consists of a large, shared center sheath and two smaller sheaths at both ends that correspond to the positive and negative terminals of the speakers or amplifier. The worker then connects the different sheaths using a thermoplastic before adding a polymer cover that is screwed on and holds the cables in place.
Mounting the banana plugs
The Audioquest ThunderBird Zero cable that was being made during our factory visit is a model equipped with very high purity red copper banana plugs. The outer housing of these plugs is moulded in polymer so as not to distort the signal’s magnetic field or cause radio noise in the conductors, as could be the case with a metallic chassis. To mount the banana plugs, Audioquest starts by applying a thin layer of copper paste on the conductors to optimize the contact surface. For cables with silver conductors, the copper paste is replaced by silver paste.
Once the paste has been applied to the conductors, the banana plug is inserted and screwed in. The plugs are cold-welded to avoid damaging the conductor. Using a solder such as tin would affect the conductivity of the cable and cause distortion. Hot welding can also interfere with the structural integrity of the conductors and greatly impair the signal. This cold-welding process is used for all Audioquest cables, from entry-level to premium models.
Audioquest cable quality control
Testing and listening to the Audioquest cables
We continued our tour of the Audioquest factory with a listening session during which we tested several Audioquest cables to compare them with ordinary cables, then to discover the benefits of upgrading from the brand’s entry-level cables to it’s higher quality cables. These tests were carried out on a basic hi-fi system consisting of a Denon Ceol amplifier and Pioneer compact speakers, then on a premium hi-fi system. In both cases, the improvement was striking, with an overall wider soundstage, better spatialization and better control of the different frequency ranges. In addition, previously inaudible details were revealed. These characteristics were more and more prominent as we moved up the range.
During this listening session, we were also able to test the Audioquest PowerQuest 3 and Audioquest PowerQuest 2 AC power conditioners. Placed between the power outlet and the Denon Ceol amplifier, they provided a noise and interference-free power supply. As a result, the listening experience was more detailed and natural.
We finished our tour of the Audioquest factory by taking a look at the different floorstanding speakers, compact speakers, satellite speakers and subwoofers from the brand GoldenEar which was recently bought by Audioquest. What sets this brand apart from other loudspeaker manufacturers is its Triton range, in which each floorstanding speaker incorporates an active subwoofer.
We would like to thank the Audioquest teams for giving us the opportunity to visit their facilities, observe the different steps when manufacturing the brand’s cables and learn more about this iconic hi-fi brand.