[Austin Morrow]

The Double Helix Cables Complement 2 cable for the HiFiMAN series of planar magnetic headphones (my goodness, that is quite the mouthful) is one of the meatiest, most brilliantly engineered, and best sounding high-end cable upgrades my ears have ever had the opportunity of auditioning. No need in giving a formal introduction here, or rather, talking about the company, as Double Helix Cables is extremely popular in the world of headphones, so let’s get to the review, shall we?

The Unboxing & First Impressions
I honestly don’t even know where to begin with this review, as it has left me at quite a stand still. Why’s that, you ask? Well, when I first got the Complement 2 in the mail, I was really impressed by DHC’s (I’m going to start calling them by the abbreviation, hopefully it’s not too confusing) presentation. An extremely nice carrying bag that’s made of micro-felt with a nylon draw-string, and it feels really, really good, hopefully I’m not the first to say that. There was however more DHC swag to be seen (Yes, these accessories are listed as DHC swag under the website, at least one audio company has some humor in their cables, it’s not something you see very often) that included Peter’s business card, some DHC decals, of which I currently have adhered to my MacBook, and an absolutely pristine flash drive made entirely of aluminum, with a laser etched DHC logo. I almost wanted to review the flash drive, it’s that cool looking!

And then came the cable. I’ll be honest, when I first set my hands on the Complement 2, my first thought was: “Jesus, this is one of the biggest, most streamlined, and utterly simplistic cables I’ve ever seen.” I really liked it a lot, the silica-sleeving was absolutely flawless and extremely smooth, and all the connectors and plugs had been ideally placed. Don’t get me wrong, the cable was very meaty and a bit hard to navigate with at first (not to mention the sheer amount of weight this cable had, it was a lot), but after a while, I learned how nice it was two have two separate cables, one for each channel in a balanced configuration. I’ve been using balanced cables for a while, but have never used a dual balanced cables that’s completely separate from each other, it’s actually in DHC’s design philosophy, and it works quite well in accordance with usability.

While we are on the subject of design and connectors, it’s probably a good idea to talk about the schematics and specifications of this cable, no? While Peter offers multiple types of options when it comes to connections and terminations (seriously though, if your mind can dream it, DHC probably has it). My particular Complement 2 came with the usual aluminum Neutrik dual 3-pin balanced connectors, and custom made HiFiMAN connectors, which were wrapped and then double wrapped with DHC’s logo. Besides the silica fiber sleeving, which is simply phenomenal when it comes to build and feel, there isn’t much going on with the Complement 2. It’s straightforward and simple, a no BS type of cable, something 
I really like.

Sonic Impressions
Ah, yes, time for the sonic listening experience. All of the above really doesn’t mean anything if the cable doesn’t sound good, right? Well, unless you’re apart of the percentage of the population that doesn’t believe in the sonic capabilities of cables, then the above statement would be of much greater significance. Anyway, enough rambling, here’s how the Complement 2 sounds, with appropriate comparisons, of course. 

Due to the fact that the Complement 2 uses OCC peptide copper as the core of the cable wire, described as “Ultrapure OCC copper litz” on DHC’s website, I had a pre-biased opinion that this was going to be of a warmer, bassy, and calmer cable than something like SPC or pure silver. While that pre-bias did turn out to be true, I did find a few surprises. The DHC Complement 2 does feature a lush tonality that stretches from one end of the frequency band all the way to the other end, and it was very apparent on my HE-500’s. A much more forgiving and natural midrange, with a slightly forward vocality presence, and fantastic coherence. A smooth treble response, a tad bit of sparkle, and very well extended. Not as detailed as SPC, but very good nevertheless, with no evidence of any blanketing or darkness up top. Transients were good too, not as fast as SPC, but very natural and free-flowing. If you can imagine a slow stream going with the pace of nature, that’s what the Complement 2 is like.

Down low, there’s not a lot of bass bloat. The lower end of the frequency band was more center stage and forward than both that of the treble and the midrange, which doesn’t surprise me at all. I actually found the bass response to be quite good, good attack and decay times down low, with plenty of impact and rumble, the Complement 2 was shaping up to be a good copper cable, and then I got that surprise, something I wasn’t expecting out of an OCC cable. 

Typically, when soundstage is being used as the focal point of a cable review, pure silver is usually where soundstage gets bumped up a notch. But, the Complement 2 isn’t a pure silver cable, it’s OCC, and it’s mimicking parts of the sonic signature that’s typically seen in SPC and pure silver cables. I don’t know if this has to do with threre being two different cables going into each headphone connector, or that it’s balanced (which can’t be it, I’ve heard several balanced OCC cables, and they’ve never expressed the soundstage I’m hearing out of the Complement 2). The Complement 2 threw me a curveball, with an exceptionally wide and deep soundstage experience, and not to mention, the imaging was absolutely stunning! Everything was placed so accurately, it was extremely holographic and life like.

Final Thoughts
The DHC Complement 2, with its warm, but detailed, and bassy sound signature checks all the marks that you’d expect out of a high end OCC cable, and then some. I was really not expecting that DHC Complement 2 to have such a realistic and massive soundstage rendering, especially for an OCC cable. Additionally, the accessories and the general customer service you get from Peter is exceptional, and if you hadn’t noticed, DHC recently lowered the price of the Complement 2 to $399, a massive price drop from its original. I have no problem recommending this cable, as it has become my reference for the HE-500.