In-akustik Reference Micro AIR Loudspeaker Cables and Interconnects Review
Mark Gusew samples some high quality, mid-price German cables sporting air dielectric technology…
Reference Micro AIR Cables
LS 104 ($850 RRP), LS 204 XL ($1,350 RRP) Loudspeaker Cables (3 meter)
NF 104 ($450 RRP) RCA interconnects, NF 204 ($600 RRP) XLR interconnects (1 meter)
You may have already heard of in-akustik through our earlier editorial, and while the brand isn't exactly a household name, perhaps it's time that changed. In-akustik is a specialist cable manufacturer based in Ballrechten-Dottingen Germany, that has traded since 1977. It has an incredible 22,000 items in its product range, one which includes hi-fi, AV, multimedia, head-fi, CDs, LPs and power cables. That level of expertise across multiple platforms allows in-akustik to control the entire cable making process, from sourcing and working with the raw ingredients to the design, manufacture and the marketing and distribution around the world.
This review focuses on in-akustik's Micro-Air interconnects and loudspeaker cables from the Referenz (or reference) selection. To get a better understanding of the technology behind them, I spoke to Holger Wachsmann, the company's Product Development Manager. Understanding that many are still somewhat sceptical of the benefits of well-designed cables, he told me that, “physics instead of voodoo – that is our credo… The best cable is the one that least affects the reproduction quality of the audio or video chain and transmits the original signal with the minimum loss.”
Holger explained that every cable – no matter what its cost or construction is – is subject to resistance, inductance and especially capacitance. These three factors make a cable act like a small circuit component once a signal is applied. A perfect cable would make no change to the signal due to these, equally across all frequencies. However, electrons interact with the cable material and the dielectric (the electrical insulator) with a small but discernible change to the original signal. No cable can improve the signal, but the best sounding cables do the least amount of harm or change to the signal. Over the years, he said, in-akustik has experimented with various geometries and dielectrics, making meaningful refinements over time.
There are various good dielectric materials available to manufacturers, such as PVC, Polyethylene (PE), Teflon (PTFE) and others; the goal when choosing the ideal material is to have the lowest possible dielectric constant or permittivity. The dielectric constant characterises the ability of materials to store electrical energy. The less stored energy, the better, because as it releases that energy it acts as a capacitor. In fact, dry air has the best permittivity of any dielectric – twice as good as PE or PTFE, and three to four times better than PVC.
In-akustik's approach is to use foamed PE insulation wrapped around the conductor, which contains tiny air bubbles within the hard plastic. This is claimed to reduce the so-called dielectric permittivity and is the basis of the company's flagship Reference cable range. Within this tier is the Air series, their best-sounding cables, with something approaching ninety per cent internal air content. To achieve this, a special plastic spacer has been created to keep the conductor perfectly suspended and separated. It's labour-intensive to produce, says the company, so is at a higher price point.
This technology has also 'trickled down' to the mid-priced Micro Air series, a new range launched back in February of this year. These cables are still hand-built in Germany to the highest standards, and use the same application of physics, but have a simpler construction, hence are at a more affordable price point compared to the Air series. As part of this review, I obtained samples of LS 104 and LS 204 XL Micro Air speaker cables, as well as NF 104 Micro Air RCA interconnects and NF 204 Micro Air RCA and XLR interconnects. Let's take a closer look at them one by one…
There are three models in the Micro Air range of speaker cables – the LS 104 with a single set of conductors per channel, the LS 204 with two pairs of conductors, and the LS 204XL with three pairs. The cables are factory-prepared into standard 3-metre lengths with rhodium coated hollow barrel banana plugs fitted, and strong rhodium coated spades costing an additional $100 a set. The LS 104 Micro Air is $850, and the LS 204 XL Micro Air is $1,350.
Common to all of the models is the use of high purity copper and concentric wire construction, where all the wire strands are wound in tight, layered concentric circles. This defined pattern reduces the irregular contact points between the wires, and the evenly spaced touchpoints supposedly harmonise the signal flow. Each conductor is reasonably heavy with an area of 2.62mm2, and covered with polyethylene; it then gets an open-spaced weave with a diamond-shaped structure. This the Micro Air technology in its simplest form, with small air chambers created between the conductors, lowering the capacitance. The thicker LS-204-XL Micro Air speaker cable has six conductors wrapped around a central soft polyethylene core which provides an airspace between the conductors; it still allows the cable to be flexible and easy to handle.
Fit and finish is to a high standard, with the connectors looking and feeling luxurious and expensive. In-akustik hasn't added barrels or paraphernalia to the cables that add weight or cost, which is refreshing. I connected all of the Micro Air cables on review into a couple of different systems, with a variety of loudspeakers and amplifiers. I used a modified Bluesound Node 2i feeding a Burson Conductor 2x Performance DAC into a Norma Revo IPA-140 integrated amplifier feeding Chario Constellation Cygnus floor-standing loudspeakers with in-akustik speakers cables.
Starting with the LS 104 Micro Air cable, and you're immediately aware that it isn't adding anything to the sound, with a tonal evenness across the frequency range. Lana Del Rey's voice in Salvatore had a purity and ease that complemented the arrangement, and the other instruments in the mix very well. Bass notes were deep and thumped with plenty of power. The top end wasn't particularly highlighted or overly lit up. The cables timed nicely, too. The music's natural rhythm and pace was conveyed as it should be, making all types of music sound fun. The track features several quietly spoken voices in the background, including a man crying in an operatic style. This was all relayed to the loudspeakers in the corrective perspective front to back.
Swapping across to the more expensive in-akustik LS 204XL speaker cable with triple the conductors brought immediate gains. Tonally it didn't change across the midrange, but it did bring added extension to the frequency extremes. There was more of everything good, making the listening experience even more enjoyable. Playing the same track highlighted a larger stereo image, one that filled the listening room with a wider, higher and deeper soundstage with better definition. It also produced more centre fill, with the image coming forward slightly, producing more intimacy with the music.
Bass notes gained added weight and extension, sounding rounder and fuller. It felt like the song breathed easier, more calmly yet with better control. All those quiet sounds in the background were easier to make out, with more space around the instruments; the reverb on the voice was also better defined and clearer. From a rhythmic perspective, the more expensive cable locked everything into place with more cohesion.
Both are fine speaker cables then, and will likely suit different buyers with systems of varying degrees of resolution and maturity. The LS 104 is compelling value for its neutrality and total purity, but if your budget extends towards the LS 204XL, then the sonic gain for the additional cost is well worth it. When you think that there are three times as many copper conductors for only seventy per cent of the extra cost, it's an impressive upgrade for the money.
In-akustik has three models in the Micro Air range of interconnect cables, the NF 104 Micro Air RCA with a single set of conductors (per channel) for $450 per metre pair, then the NF 204 Micro Air RCA with two pairs of conductors at $570, and a single interconnect with an XLR balanced connector, the NF 204 XLR Micro Air also with two pairs of conductors for $600 per metre pair. These cables are available in 0.75, 1.0 and 1.5 metre lengths.
Using the same engineering principles behind the speaker cables in the Micro Air range, the wire used to construct the interconnect cables is made from high purity copper that also has a concentric wire arrangement with nice evenly spaced touchpoints. The NF 104 is arranged with a normal coaxial cable architecture, but with an added polyethylene jacket providing an air pocket between the conductor and the double shielding. The Micro Air technology is further enhanced in the NF 204, which has two separated conductors kept apart for air to lower the capacitance with a polyethylene jacket within a double-shielded cable sheaf.
In-akustik has created a new RCA connector to suit its needs and to complement the Micro Air series, with a completely solder-free connection. The company explains that there's always a certain variability in the quality of soldering, as even the best staff can have a bad day. So the connector has several parts that are joined together, which include contact pins made of tellurium copper and coated with rhodium. The join with the cable is done via a 1.5 ton high pressure pressing for consistency and reliability. The XLR connection is hand soldered, with quality checks carried out.
The cables are covered in a black and white polyethylene jacket with an arrow on one end of the RCA cables to indicate the preferred signal flow, for the best sound quality. Strangely there are no left/right designations or coloured stripes on the cables or ends, so care is required to set the channels correctly. These interconnects are refreshingly slim and wieldy – light in hand and easy to position at the back of an equipment rack. The connectors look lovely with the rhodium coating immaculately finished with a high lustre.
Unsurprisingly perhaps, all three interconnects showed many of the qualities of the in-akustik speaker cables – there's certainly the family trait of neutrality and tonal evenness. Firstly with the NF 104 Micro Air RCA, the piano in Looking for Love by Kingswood was lovely and real, with a crystalline tonal purity throughout its range. It had fast attack and good sustain of the piano notes, yet still seemed tonally balanced. I wouldn't call it warm sounding, but neither would I call this cable cold; it strikes a nice balance.
The cable proved highly detailed, allowing the soft passages of the track to be fully fleshed out; the opening note of Looking for Love rang out nicely into a black background. I also enjoyed the transient speed, realistic dynamics and all-round cohesion. For example, the snare drum timing was impeccable, and there was plenty of motive force, too.
Switching to the NF 204 Micro Air RCA cable was a larger improvement than I'd expected, considering its $120 penalty. The soundstage immediately grew in every dimension, with the singer moving a half step closer to me, yet with more front to back depth. There was nothing negative to hear with the thicker cable, only greater levels of detail, and a fuller, more 'meat on the bones' sound.
Bass notes had greater weight and dug deeper with that added extension. Dynamic crescendos got more impact, while those tiny musical accents were carried more accurately. Vocal harmonies sounded fuller and with added body and coherence, and there is a touch more extension to the high frequencies too. It was as if the window between myself and the performance had been given a thorough clean-up and polish. All this was also true with the XLR version I tried too, too.
I compared the in-akustik interconnects with my reference Tara Labs 'The 2' cables which are over three times the cost, yet they proved only marginally better in some respects. They produced an even larger soundstage and amount of inner detail, but have about the same opacity with perhaps a little less speed than the in-akustik cables. Colour me impressed, especially considering the cost differential!
Audiophile interconnects and speaker cables remain a contentious subject, with some hi-fi fans regarding them as poor value for money compared to electronics upgrades, for example. Yet in-akustik's Micro Air range does not fit into such a category; it's old fashioned high quality, high-value fare that offers easily discerned improvements to people with mid-priced systems, or above. I couldn't help but be impressed by the whole range.
The company is not the first to talk about air dielectrics, but it has certainly made the science work in practice. I was impressed by the tonal balance, transient speed, high-frequency extension and the lack of additional artefacts common to everything that I auditioned. These are family traits that distinguish in-akustik's Micro Air range from others. Overall then, highly recommended on both sonic and value terms.
Starting his first audio consultancy business in the early ’80s whilst also working professionally in the electronics industry, Mark now splits his time between professional reviewing and AV consultancy.