7N (99,99999%) purity wires, made using the company D.U.C.C. Stressfree (D.U.C.C. = Dia Ultra Crystallized Copper) technology. In its materials, the Mitsubishi company points out that impurities in copper are not only the so-called diode effect occurring at the points of contact between crystals, eliminated in PCOCC wires by maximally elongating the crystal, but also impurities inside the crystals (PCOCC = Pure Crystal by Ohno Continous Casting). Engineers came to this conclusion, having analysed X-rays. During the D.U.C.C. process, copper crystallizes again and impurities are released and removed. Such copper displays much less of the directionality effect, but it is marked on Acrolink cables anyway.

The material used for the company cables is not only processed in the D.U.C.C. process, but also in another process that leads to the limitation of inner stresses – that is why we can find the term “Stressfree” in leaflets describing individual cables. The thing is that when wires are pulled out mechanically, especially when they are bent, stresses affecting signal transmission and ultimately the sound are generated in the material.. So, the Mistubishi company subjects them to a process which eliminates internal stresses. However, the company emphasises it is not “aging”, i.e. artificial softening of the material. It still has all the advantages of cables from the ‘9000’ series, i.e. wonderful colors, great imaging and sonority, while it brings resolution and sonority to a higher level. Everything is a little more “taken out” from the background, even though it seems that the previous cables sound brighter.