Atlas Arran Ultra L RCA Grun
This review started slightly differently to the norm. A friend came to listen to some music and asked if I had a spare interconnect in the many boxes of cables that have built up over the years. So we started to listen to a few of those that I reckoned were unlikely to see much use, some of which are over 20 years old and had not been leading a very productive life. One such was a navy blue Furukawa PCOCC cable that I had been given in the nineties and which turned out to have some very appealing qualities, it was notably more fluent and refined than my regular interconnect and while it may not have been quite so detailed, made the sound of digital sources in particular that much more appealing. I recalled that Atlas use the same Ohno continuous cast (OCC) conductors in their cables and contacted the company to try an example to see if it would deliver the same results I had heard with the vintage Japanese cable (which has stayed in my collection).
What they sent was two pairs of the penultimate interconnect in the range and the best copper cable that Atlas makes, the Arran Ultra L RCA Grun. Richard Barclay reviewed a very similar incarnation of the Arran RCA interconnects less than two years ago so it wasn’t exactly on the radar for a revisit but I hadn’t heard those cables myself and was fascinated to hear what this modern OCC cable could do. The only change since the early Arran is insulator used within the plugs, these are made with a polypropylene Latik 3D printed insulation rather than the nylon of the earlier version. Unlike PTFE which expands when it heats up, and consequently changes resistance, Latik is thermally stable which means that resistance remains constant in connections with a power amp that generates a lot of heat for instance. Latik is also made with the minimum of material so that there’s more air and less plug, which when you realise that air is the ultimate dielectric/insulator, begins to look like a good idea.
The OCC conductors in Arran Ultra L are insulated with lapped rather than extruded PTFE for the same reason, it means that there is more air around them which helps to give this cable its wide bandwidth. Atlas also use copper from the same OCC batch as the conductors to make the pins in the RCA plugs so that you get continuity of material from one end to the other. The pins are silver plated to avoid oxidisation as are the collars within the plug.
The Grun element of the name relates to Atlas’s cable grounding system. Most RCA interconnect cables have the internal screen connected to one or both plugs and this goes some way to keeping noise away from the signal. With Grun equipped cables a flying lead allows the screen to be connected to either an external independent reference point, essentially the earth on the mains supply or to a chassis ground point on the equipment you are sending signal to or from. As a rule it’s best to have the end of the cable with the Grun connector on the preamplifier or integrated amplifier, which means that Arran Ultra L is not a directional cable, because in a pre/power system both the incoming and outgoing signal cables are generally grounded at the preamplifier.
You get an earthing connection in the box with Arran Ultra L Grun cables that can be connected to an earth point on the component. Alternatively Atlas sells Grun power adapters (above) which are mains plugs with connectors in various types to suit different international zones with the UK one being a conventional 13A plug that only has an earth pin. The Grun earthing cables attach via threaded and silver plated connectors that are a bit of a fiddle to join but you only have to do this every time the interconnects get tangled up as a result of too many equipment changes! Which is an issue for busy reviewers but not one likely to affect those whose systems remain relatively static, in truth I have learned to move the end of the cable without the Grun leads in order to avoid this issue.
Sound quality
I reviewed two pairs Arran Ultra L RCA Grun but started with one replacing my usual interconnect between DAC and preamplifier. The result was not subtle at all, I usually get a change in imaging or a small improvement or loss in timing with interconnect changes but this was massive. The increase in resolution felt like the sound had gone from flat to three dimensional, with all the colours of the acoustic rainbow rich and vibrant in front of me. To use a photographic analogy it was almost like going from black and white to colour imagery.
Naturally this inspired me to put the second Arran Ultra L between preamp and power amp, I had to hear more of what this remarkable cable could do. Once again the sound expanded to produce what appeared to be the full picture, with all three dimensions plus time resolved to an uncanny degree. There was just so much going on that it took a while to come to terms with. It was at this point that I started to wonder just how expensive these cables are, quite a lot is the answer, the full extent is revealed below. However, we are talking about world beating sound quality that makes all the other interconnects I’ve had the pleasure of using sound dry and slightly opaque.
Atlas Arran Ultra L RCA Grun achieves this as a result of all the work that Atlas have put into the conductor, its dielectric, topology and construction along with the efforts they have made to produce an RCA plug that loses the least amount of information. I did wondered whether it was all down to the Grun earthing system, as I haven’t had a cable like this before, but removing that from an actual ground point means that you have an aerial that will pick up noise and pollute the signal so not using it properly is worse than having it at all. And this part of the equation was on the first pair of Arran interconnects reviewed and they didn’t appear to blow Richard’s mind.
I tried them with the Bricasti system reviewed a few months back and was gobsmacked by how much was going on, how much detail was suddenly revealed and the extent to which that extra detail made the music that much richer and more beautiful. The guitar on Shine on You Crazy Diamond for instance was savage yet not piercing, the backing vocals were easier to follow and the way that the saxophone images was significantly stronger.
It’s just possible that Arran Ultra L sound may be too rich and well rounded for some tastes or systems, if you like a lean, speedy sound that puts you on the edge of your seat then there are plenty of alternatives to choose from. I want to hear as much of what went into the recording as possible and these cables deliver a heck of a lot more of it than most. The sense of notes being fully rounded and tonally rich is particularly appealing but would not turn my head if the timing was not spot on as well. The quality of immediacy is what makes a system sound real, it makes you want to listen, so it’s crucial and this cable does it as well as much less revealing alternatives.
Conclusion
What Atlas have done with the Arran Ultra L RCA Grun sets a benchmark for cable resolution that few alternatives are likely to reach, when used with the Grun power adapter they resolve fine detail to an astonishing degree. What Atlas says about noise being the enemy of sound quality is absolutely true, and they have managed to eliminate more noise than the majority of competitors. If you can keep EMI and RFI noise away from the signal you end up with a higher effective signal to noise ratio and that means more music and fabulous sound. I have inevitably ended up in situations where I need a third interconnect, for a second source usually, and the need to use something else always compromises the results of a pure Arran Ultra L RCA signal carrying chain. It’s one of those components that becomes more essential the longer you use it, this cable is addictive.