HiDiamond Diamond 4 power cable review

As it seems there in an abundance of high-end audio cables coming in for review. As with all the other high-end products, each year seems to be exploding with the vast offerings. I’ve been contacted by the HD-Roma for the test and review of their flagship cables and few weeks after the package arrived. Italians do it better ? For sure. HiDiamond Roma audio cables appearance is for sure different and stand out. They instantly evoke the interest and speaks for themselves in being the attention grabber.

Why another cable review? Well, for all of the upcoming ones, I’m strictly choosing those, that catches my attention for some apparent reason. Particularly with HiDiamond Roma their dedicated technological approach and dedicated four times copper baking seemed to offer something different. There are enough of the cables on the market, which uses the similar tech and materials. I’m always intrigued and interested, when somebody takes a different root. And HiDiamond manufacturing process is elaborately different.

Let us look into the building blocks of HiDiamond Diamond 4 power cable:

“New power cord HiDiamond reference from design, technology and performance. A new frontier for all worldwide cable manufacturers in this field. Cable with 4VRC© proprietary technology, copper cooking four times in order to obtain a reduction of the values of inductance, capacitance and resistance mixed with graphite. The best Carbon Fiber connectors and contacts in Plating Silver to ensure maximum energy transfer. Graphite in this solution allows to block the noise generated inside the cable from the electrical signal (which is nothing the music signal) to bring out a perfect signal without introducing noise that would spoil the end result. PVC insulation.

Double shielded braid SILVERED copper with graphite to eliminate any interference, allowing a better lossless signal transmission. Twisted technology inside the cable to have a tonal balance outstanding.

Nothing was left to chance, as well as the aesthetics that should ensure a harmony with a truly hi-tech product. The dynamism, greater focus, are incredible details that make it a masterpiece and then the reference. A cable that is present but does not feel. Indicated in all facilities at both solid-state valves of any value.”


HiDiamond Diamond 4 power cable 4VRC © technology was intriguingly interesting. This approach double the cable cooking times and HiDiamond team found quite few advancements in using this technology. Let us look in HiDiamond official explanation:

“4VRC © technology: means the adoption, as a conductor, copper baked four times, in place of the 2VRC used by other competing companies. This technology makes it possible to achieve greater purity than that obtainable through normal cooking (two times). Also means that the braid/capillary is processed at different temperatures four times instead of two. The purity of the source material of the cable is decisive.

Copper is made available for processing in the form of wire rods (16 mm section and 100 feet long), which is extruded and calibrated until it becomes a strand of 0.10 mm section for 10,000 meters in length. The greater the purity of copper, so it will be easier to achieve small sections, with high endurance and fragility modest features that allow a perfect calibration and homogeneity of discriminatory elements section, especially in the case of power cables, where more is reduced the diameter of the capillary, the more it reduces the skin effect. In smaller signal cable is the capillary diameter becomes more simple get the right compromise with the dielectric and the amount of graphite used in mid-range cables and high-end. This procedure ensures that the filament is much purer than those processed with traditional technology 2VRC, ensuring that values of inductance, capacitance and resistance very low.

XLPE: 100 times better than normal teflon. This lowers the threshold of spike's escape and therefore the width of the musical signal barrier guaranteeing greater linearity and low amplitude of the sine wave of the basis for the benefit of the naturalness of musical signal emission

Graphite: mixed with copper in 4VRC © technology, allows to block the noise generated inside of the cable from the passage of an electrical signal (which is nothing the musical signal) to bring out a perfect signal without any introduction of noise that would spoil the final result.”


HiDiamond Diamond 4 power cable represents the company reference cable series. They tried to put all the efforts and careful selection of building materials for the maximum performance. Aesthetically Diamond 4 is an instant eye catcher with the silver plastic ( plexiglass ) mesh cable covering and carbon fibre power plug. Diamond 4 also spots two plastically barrels with the company logo, that aside of design acts also as resonance absorbers. Diamond 4 comes with the semi stiffness. This shows the sturdy design, that will hold on for years and still let the cable to adopt to bending when needed. Some of the recent cables I’ve had for test and review were practically non bendable and this limited their practical use down to few percents in real life use.

HiDiamond Diamond 4 power cable takes a clever design approaches and selected materials and approaches in creating something unique.

HiDiamond sees, that resistance is linked to features of metallic material that constitutes it and a good cable should have a as little resistance possible in ensuring the lowest attenuation of the signal. For them low value of this parameter is important especially in presence of high amplitude signals. That further ensure, that signal/ratio is high enough.

To continue in the company vision. If the capacity is low the speed of propagation of the signal will be greater. The capacity of the cable increases proportionally to the length of the cable and is linked to the characteristics of the dielectric material given that not all the energy of the signal cable is meant to arrive at destination.

Load metal conductors of the cable stores the electrostatic energy in the same way as an armour of a capacitor. Greater the permittivity of the cable, the greater the energy that is stored by the dielectric to be released, causing a phase shift that wipes out a portion of the transmitted signal by creating a background noise and not linearity of the musical signal. A good dielectric material has a low dielectric constant value so as to allow greater speed signal propagation and a lower capacity of the cable itself. For this our used inside the our cable , XLPE dielectric, which for this type of "work" is 100 times better respect to Teflon (the dielectric used by most manufacturers of cable).

At HiDiamond they see inductance is related to the geometric and structural parameters of cable and depends on the diameter. The quality and refinement of the conductors and their configuration bring even more. For them the braided geometry brings low inductance and that is wanted as high inductance causes storage of electromagnetic energy that is returned in the form of signal distortion. The greater the inductance, the more it reduces the bandwidth.

Consistency of diameter of the primary conductor insulation and diameter of outer conductor creates the difference. For HiDiamond this is the reason why you don't make major 100 m coils in the audio field and would be very costly to maintain such a standard for lengths. If the copper is not a minimum 95% copper or a copper alloy is in absence of the optimum electrical characteristics (type derived alloys from lead) you can't get proper reduced diameter strands.

For this reason the minimum size of the coil core is 160 mm in diameter with the power cables.

Importance of cantering is of highest importance for the company. They feel, that the way the wire, insulation and sheath are assembled must be absolutely precise, constant and cannot be done by hand. Thus ensuring the perfect results.

HiDiamond uses the technical approach check ups at the various stages of the manufacturing process. The measurings ensure the proper performance and continuous quality.

At the final stage HiDiamond welding or crimping machines connect connectors to the finished cable. They’re using tin with high percentage of the silver. Final tests check out connections and capacity, resistance and inductance are being measured again to ensure a uniformity of performance.


During my listening test I’ve complied quite some observation notes. They all lead to very same conclusion. The consistency of performance. Many of contemporary high-end audio cables works as some sort of filtering element rather then bringing excited performance. It was never so with the HiDiamond Diamond 4 power cable. The difference in plugging in the Diamond 4 instead of normal power cable were evident at once. Intriguingly the difference in quality was also presentable with the comparing of few other power cables in the similar price range and above.

Music was being affected with additional presence and impact. With many high-end audio cables one need to take a prolonged listening session in finding out the subtle changes, but Diamond 4 brings the evident change almost instantly.


With all the attention and specific takes, that HiDiamond uses in the production of Diamond 4 power cable the result is evident. HiDiamond Diamond 4 power cable brings the flow to the energy of the music and doesn’t act in any way as a filtering element like many power cables do. This is well thought out mature product, that clearly went through many phases in reaching the point of performance, that is offering.

For the asking price HiDiamond Diamond 4 power cable is more then fair. It comes with the real down to earth pricing. Its realistically priced and comes as a stylish and technically empowered package. Made in Europe and with the implementation of 4VRC cooking as well as their custom technical approaches, Diamond 4 step up to the many so called high-end audio cables.

HiDiamond Diamond 4 power cable represent a valued product with the expected performance, that brings what its promising.

Technical characteristics: 

External jacket. 19. Number of cond. 4X6mm. Cond. Copper (4VRC) and Graphite; Capacity max. C1/C2 220 Pf 110Pf with Schild.; Conductor Resistance: 3.3 OHM/km.; Inductance: uH/0.7 m.

Price: 1.815,00 EUR / 2m


“We wanted to first thank Matej Isak for the professionalism they have always sported and excellent analytical skills highlighted, which allows it to be always ready and accurate. Indeed, we believe that also in this case has centered the sense of the cable HiDiamond Diamond D4 under test, which has been studied for applications true hi-end .

HiDiamond was born fourteen years ago. We have achieved the highest awards in Italy and in the world in the field of the audio and video cables. In this time, we have worked hard to improve our brand and our image. We always say that it is difficult to succeed, simple to fall. We do not feel satisfied, and yet we want to grow.

With 4VRC © technology, we went ahead with performance ever higher. Now, we can design a new concept for cables for arrived at the max performance audio. 

Not least, our mission is to give the highest quality, at the lowest price possible.“