In a world filled with complete audio systems, Linn’s latest range-topper is perhaps the most ‘systemic’ of them all. The Klimax system does not have a high degree of mix-and-match potential; the streamer feeds the digitally active loudspeakers, and any substantial variations on that theme demand stepping back from that top-of-the range concept, using passive crossovers, separate power amplifiers, and so on. This runs counter to Linn’s ‘source is in the speaker’ ethos, which really has its ultimate expression in this system. We’ll come back to that later.
Last year, Hi-Fi+ looked at the latest version of the Linn Products Klimax DS/DSM network music player with its new Katalyst DAC architecture. As the streamer was partnered in many cases with the Linn Klimax 350 loudspeakers, with its own Exakt room compensating digital crossover network, there was a slight hole in the storyline where those with Linn’s top loudspeaker were missing out on the full benefits Katalyst can bring.
This year, the ‘architecture’ developments in Katalyst have now reached the Klimax 350 loudspeakers, and if the effect was exceptional in the DS/DSM models, it’s a total revelation in the Klimax 350. OK, so the name sounds a bit like the title of a rapper’s difficult third album (‘Klimax 350 Loudspeaker, featuring Katalyst DAC Architecture’), but it’s the only real way to explain how this works.
It’s hard not to extend the ‘remix’ idea out to the products, too, because both streamer and loudspeaker are not new products, but revised, updated, and – best of all – upgradable versions of existing models in the Klimax line. Essentially, as a system, what we have here is a hub-like version of the Klimax network music player, one that only features the RJ45 connections between DS and loudspeaker, with the Exakt – and now Katalyst – processing and the active power amplifiers built into the back of the Klimax 350 loudspeaker cabinets.
But what is Katalyst? Put simply, it’s a sophisticated series of power supply checks and balances to ensure the DAC is working as per the original and best intentions of the digital designer. Unlike many digital systems, where digital conversion is effectively dictated by the circuit design laid down by the application board of the chip design company, Linn sought a chip ‘fabber’ that produces a design that allows the company to drill deep into its power supply and logic feeds, and ended up with a board that doesn’t just supply a single voltage to the DAC, but provides two separate voltages for modulation and three for current to voltage conversion, all of which are fed from highly stable and isolated voltage sources. If you consider how important a power supply can be for a product like a preamplifier, the ability to control the power feed of the digital converter to this degree of sophistication makes the chip extremely flexible. Of course, it was handy that Linn liked the sound of that particular chip on audition!
The quality and consistency of that power feed alone makes a big difference to the performance of the DAC, but that’s only part of the Katalyst architecture. The signal is fed through a data optimization process (a 16x, 768kHz upsampler working at 35 bit precision, then to a 8x, 6.144MHz modulator) before being passed to an array of bitstream DACs, and finally passed to a revised analogue output driver. A high precision master clock governs the whole digital signal path from upsampler to the main conversion of the DAC array. This data optimization system largely obviates the need for super high-resolution files and DSD, because the upsampling process raises 16/44 to 24/192 PCM files up to such a high performance level internally. If you are keeping up with all things Linn, you may well find this has a lot in common with the Katalyst-strength versions of Linn Klimax DS and DSM digital players, because it’s the same concept, in a speaker!
Linn has not been shy to criticise and comment upon what it considers ‘closed’ formats like DSD and, more recently, MQA, so it’s perhaps little wonder that these formats are not supported through Linn’s system. In fairness, Linn is extremely consistent in its drive for open source, as it both welcomes third-party app designers and invites loudspeaker designers, engineers, and enthusiasts alike to explore Linn’s design tools. OK, so visitors to the factory never get past the entrance to the research and development floor, so ‘open source’ does not extend to ‘open to espionage’, but the company is surprisingly and refreshingly transparent in its stance on design. As a result, if you already have a Linn Klimax system with a pair of Exakt-ready active Klimax 350, you can upgrade them to support Katalyst, and you can even upgrade still earlier models with a set of complete Exakt modules. But if you haven’t gone down the Linn Klimax 350A route, there are also Exaktbox upgrades for users of some older Linn, Bowers & Wilkins, Kudos, and KEF models. There is even a ‘roll your own’ concept for designers and builders.
The simplest way of describing this raft of options here is if you have an existing pair of Klimax 350s with the Exakt module, the back plate with all the electronics is taken off, and the cruciform central circuit board (containing DAC and Exakt digital crossover, and associated power supplies) is replaced. The new board looks superficially similar to the old one, but the intervening years have radically improved FPGA designs, and this one now has double the digital horsepower but takes up half the size. This allows the individual subsystems in the board to be more physically isolated from one another, and also allows the Linn engineers greater scope for processing.
To discuss the Klimax DS or DSM network music player at length, we refer you to our review in issue 140, but the slimline version of that review is that of one of the first network players (dating back to 2007, which is equivalent to the early Jurassic era in networked audio terms) to take the format seriously. The Klimax DS player and DSM player/preamplifier were subject to one major revision a few years ago, and the Katalyst updates last year. The player is an elegant standalone streamer in its own right, and the Katalyst upgrades take the already excellent Klimax into new heights. For use in a full Klimax Exakt Aktiv system, though, the full-fat Katalyst Klimax DS or DSM is gilding the lily somewhat, as the digital audio conversion is performed inside the Klimax 350 loudspeakers. So, for the last year or so, the best Linn digital audio stream was not the best Linn system, but an analogue Aktiv system with a Katalyst-enhanced Klimax DS or DSM. The source – temporally – worked best outside the speaker.