The stock Diana cable is 1.5 meters (5 FT) in length (not 1.2M) and offers proper balance with our headphone.
In terms of sound, you're welcome to your opinion, but in my experience in designing cables a typical teflon insulated silver conductor has a leaner sound. It may work for you if you have a soft or bloated sounding system, or appreciate a brighter presentation, but in my experience it's a fault to balance out another fault which skews the decision making process going forward in terms of system upgrades; will always need to choose gear, interconnects, AC cables, etc. that stray toward the darker side of neutral. Not to mention the teflon jacket is a bit stiff and will translate motion noise to the headphone.
In terms of connection to the Diana, the extended 2.5 mm stereo plugs used on that cable were originally designed for the likes of cel phones, not Diana, so lacks proper strain relief and will place stress on the headphone jacks rather than the headphone shell as designed. Diana should interface to a 2.5 mm mono plug whose body just fits inside her shell so the cable connector body translates force to the headphone shell, not the jacks inside Diana. ABYSS cables have injection molded 2.5 mm gold mono connectors to perfectly mate with Diana.
(Aftermarket manufactures should use connectors similar in body diameter to a Switchcraft 880X where the body of the 2.5 mm plug just fits inside the recessed jack opening of Diana.)
Customer can order any of our headphones with a custom cable length (cost depends on length), just need to ask. We also sell stock Diana cables in longer lengths and different amp plug styles, most customers who use her portable and desktop have more than one cable.
Being a cable manufacturer we also offer a very nicely hand-made Superconductor HP upgrade cable for those with exceptional gear designed to take resolution to another level while maintaining spectral balance (not pushing a tonality shift at you in an attempt to do the same), very tricky thing to do in cable design. Sure it's expensive, but if you're connecting say a Diana Phi to a system North of $10K what this cable offers is priceless.