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The GAIA GYBRID design / construction
The Gaia Hybrid designs are an evolution from our standard Gaia designs and as a result they share many aspects in regards to their basic construction and design aims. With Gaia Hybrid we further exploit the full potential of Gaia Litz conductors in embodiments that are not compromised by cost saving concerns and labour intensity.
The conductors of Gaia Hybrid cables are Litz type wires. Each conductor is formed by individually insulated discreet conductors. They are all made of high purity OCC silver and Teflon insulation. So what makes them so different? Although one may assume that it is the type of silver used that makes these conductors stand out, it is the sum of many less obvious elements that make these conductors so distinctive. The cable geometry, the type of primary and secondary insulation that is used on the conductor, its density and thickness; the proximity, alignment and the selected size for each of the discreet conductors are only some of the factors that result to major differences in performance among seemingly similar cable designs.
Designing the signal conductors: Several aspects need to be addressed when designing the signal conductors of Gaia Hybrid cable. We have to determine a fixed proximity among all the discreet conductors in a Litz wire. To achieve this, we need a primary insulation with set thickness, which is firmly attached on the metal core preventing any movement of the individual wire. Free movement of the individual strands not only causes the wire to “hit” against the inner wall of the insulation but more importantly changes the relative proximity of the discreet conductors. Further more, the primary insulation has to be airtight. Teflon (PTFE) in its solid form, offers an extremely well suited type of dielectric considering its, electrical and chemical properties that remain very stable across a wide range of frequencies and temperatures. At the same time, solid Teflon needs only to be applied in a very thin layer to achieve the desired results, without risking mechanical wear from friction and bending, aging and moisture absorbency often observed in softer (or porous) types of natural or synthetic types of insulation. The use of thin layers also allows a far greater degree of conductor flexibility while maintain a very strong conductor far less prone to breakage than bare solid or bare stranded conductors. Note that at this stage, Teflon replaces the enamel that is typically used on Litz wires. Most types of enamel account for some of the least desirable dielectric properties for hi fidelity audio cables. The precise thickness of the primary insulation will vary from one cable type to the other (depending on the requirements of the individual design). However, we want a primary insulation significantly thicker than the film insulation (enamel) found on typical Litz wires but much thinner than the typical types of insulation used on solid core wires.
In order to achieve the above formation for each of the discreet conductors contained inside a litz wire we had do innovate and develop unique techniques for manually extruding the solid Teflon over each of the individual silver strands. Such a manual type of extrusion eliminates the requirement of high temperatures and ensures that the inner wires remain free of any surface marring. The downside is that the process of insulating these wires is extremely time consuming.
The size of the individual stand: Another major departure for the Litz wires typically found is most of the audio cables is the strand sizes we use on the Gaia Litz wires. Most Litz wires are designed and produced for use on high frequency and or high power applications. The major consideration in such applications is the impact of skin effect and the related power losses that can be experienced. When it comes to analogue audio applications the considerations are very different and one cannot simply borrow a high frequency cable design and apply it in audio, claiming the same benefits. The selection of optimal strand sizes in Litz wires primarily depends on the operating frequencies, the RMS power and the required lengths of a cable. What we often come across on Litz wires in audio (i.e. a large number of very thin wires) simply produces results entirely inconsistent with the needs of the audio signal. Analogue audio signal is far more complex. It covers a broad frequency range with the human ear being able to detect even the smallest shifts in terms of time, power and shade on each of the fundamental elements in a musical passage. The optimal sizes of the discreet conductors used for low level audio signal (20Hz-20kHz) tend to be larger than what typically is used for high frequency/power applications (which is quite the opposite from what most people involved in audio tend to suggest).
Maintaining simultaneously the optimal size for both the discreet conductors and the whole Litz wire can be a big challenge; but it also offers the potential to create the most perfect wires for each application. Whereas out standard Gaia wires are formed by selecting a single size of discreet corductor/strand, the Hybrid Gaia wires combine multiple strand sizes to optimize performance across the audible frequency range.
The last advancement of the Gaia Hybrid over the standard Gaia wires is their significantly lower resistance due to the larger effective conductor size. Such an improvement was done in full awareness of the impact it can have in the overall balance of the other electrical characteristics of the cable. Hence the increased conductivity was achieved alongside a favorable balance between capacitance and inductance maintaining (or even further lowering in some cases) the ratios that exist in our standard Gaia cables.
Forming a Gaia Litz conductor: After aligning the individually insulated strands we apply the secondary (outer) insulation of a Litz wire. This is formed using 1-3 layers (depending on design) of lower density PTFE. The insulation here has various roles. It is a “packing” medium used to hold the aligned discreet individual strands in a fixed position while the cable moves/bends. It determines the proximity of the encased Litz conductor to the other conductors of the cable, having a direct impact to many electrical parameters of the cable (capacitance, inductance, etc). It affects the mechanical characteristics of the cable. Hence the type of insulation used (with its electrical and mechanical properties) as well as the density and thickness of the material are extremely important parameters in the overall performance of the cable.
At this stage. We have formed a Gaia Litz wire. These wires will typically need to cure mechanically for around 48hrs before they can be incorporate in the cable embodiment.
So, how will such a Gaia Litz wire sound? Will it be so much better than the cables you already have? A Gaia Litz wire is simply a conductor, and a single conductor has no sound or sonic characteristics. It is the entire system of wires along with their dielectric (i.e. a complete cable) which will determine most of the relevant electrical parameters and will have a certain impact on the sonic presentation of an analogue audio system. Choosing how to use these Litz wires to a positive effect is an entirely separate part of the design process and the one that will effectively lead to a “better” or “worse” cable. Designing or selecting the conductors is simply a starting point and although a well designed and produced conductor has the potential to create a great cable it does not guarantee so.
The cable design. When addressing a cable design, we always have to make some basic but very important choices. What is the application of the specific cable? What are the characteristics of signal that will be handled by the cable (these are determined by the interconnected components)? Anything, from the RMS, operating frequencies, distance, mechanical characteristics, overall size, operating environment (EMI, RFI, temperature, humidity) is a factor to be taken into account when determining the most suitable design.
In general the Gaia Hybrid designs produce symmetrical, shielded (Twisted Pair and Starquad) and Triaxial cables. The Twisted Pair and Staquad geometries are in our opinion the most consistent methods of transmitting analogue signal on both balanced and single ended connections, allowing the “signal” and “signal ground” (or the signal “send & “return”) to be handled by dedicated, symmetrical paths and remain isolated by the EMI/RFI shielding structure of the cable. Furthermore, these geometries, when applied in an appropriate manner, they maintain a low degree of intimacy between the conductors and ensures that capacitance is kept at low levels.
The combination of correct proximity and low density PTFE dielectric among the conductors results to cable designs with low resistance, low capacitance and moderate levels of inductance (a proven recipe for the ideal connection of low level analogue interconnects).
The Gaia Hybrid cables feature a 3 layer shielding system which is applied in adequate distance from the inner signal conductors. Each layer is formed by different materials. An inner layer of nickel and fiber mesh is applied over the PTFE “bedding” insulation. This is a thin layer of 100% coverage with 50% overlap and ensures that any “stray” stray unwanted energy from the main shields is kept on the outer structure of the cable and “re-routed” back to the main shielding system and to the ground. The main cable shield is formed by a high density braid of pure silver plated OFC copper strands. This is a very heavy gauge component which offers an extremely low impedance connection to the ground and an option coverage of over 98%. An additional layer of braid is formed by steel strands. The nature of this component allows a better control of low frequency noise which requires a larger skin depth and the use of ferrous metals. The shielding system of the Gaia Hybrid cables ensures that interference will not get into the system of the signal conductors and it will be routed to the ground in the most efficient way.
The outer layer of insulation of the Gaia Hybrid cables depends on the application each cable will be used for. Whichever choice of material is made, we always ensure that the outer layers of insulation can protect the inner cable from both mechanical and environmental wear. Typically the Gaia Hybrid cables have a multi-layered outer isnulation formed by a thin layer of Teflon applied onto the outer shield, a PVC or silicone jacket (depending on the degree of flexibility that is required) and an outer raided sleeve - usually, a dense, soft, synthetic multi-filament braid. Other types of finish are available upon request although we believe that our choices are the best ones to ensure a user friendly which will last for a very long time.
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