Linn Klimax Solo 800 Power Amplifier

REVIEW
by Alan Sircom
Apr 24, 2025

Most audio companies stay in their lane. They make electronics or turntables or loudspeakers. Some go ultra-specialist and make just one subsection of those fields, such as cartridges or preamplifier. A few brands make a complete system. But only Linn makes full-on audio ecosystems. And the difficulty with making a complete ecosystem is ‘point of entry’. In the high-end, there are many outstanding loudspeakers out there that were outside of Linn’s purview because the company didn’t make a power amplifier with the gravitas and muscle to drive them; Linn cracked that nut with the Klimax Solo 800 mono power amplifier.

The easy route for Linn would have been to take its previous Klimax Solo 500 amps and beef them up. The Solo 500 was a great performer in its own right, but was intended to play nice with eight ohm loudspeakers, and the occasional sub-two ohm parts of a high-end loudspeaker’s impedance plot didn’t sit that comfortably. Beefing up the Solo 500 would make for a relatively low distortion amplifier… but ‘relatively’ wasn’t in the Klimax Solo 800 brief.

The brief, briefly

Instead, Linn wanted to plant a flag in the high-end power amplifier market. And not just any flag; it wanted to plant The Definitive Statement flag in the high-end power amplifier world. To do that, the brief was simple; give it vanishingly low distortion across the board, make it able to drive any high-end loudspeaker you can think of to ‘healthy’ levels, and do it with headroom to spare at all levels. Oh, and it needs not to double up as a heat source and rack up the fuel bills in the process. Reshaping the world of high-end audio amplification in a single stroke; how hard can it be?

Putting on the cynical hat on for a moment, maybe changing the amplifier high-end need not be quite as Herculean a task as one might first imagine. There is a lot of laurel-resting going on in that arena. A company might have made a ground-breaking design or two to make its reputation back in the day, but since then the same company has simply reinvented the wheel, often with minor variations on the same theme. Arguably, the last product that shook the amplifier tree was Devialet with its Class ADH-based D-Premier and subsequent shiny pizza boxes. While ultimately Devialet didn’t up-end the high-end amplifier industry, it had an impact. Linn’s Klimax Solo 800 has the potential to have an even bigger impact.

Linn Klimax Solo 800 lifestyle

Why? Because although what happens on the inside of the Linn Klimax Solo 800 is different to the high-end mainstream, it’s capable of being slotted into an existing system without completely redrawing that system. Devialet’s great selling point was also its great limitation; it replaced everything except a turntable and loudspeakers. That’s something not everyone wants to do; they might like their digital front-end or preamp. Even the box-count reduction wasn’t much loved by die-hard audiophiles, where every shelf in the rack tells its own story. While going down Linn’s ‘Exakt’ digital ecosystem route does require the listener to change almost everything to Linn’s own components, Linn’s Klimax Solo 800 mono amps are analogue power amplifiers and can be a direct replacement for your existing mono amps, or an upgrade for stereo designs.

Poor push-back

That’s not to say Linn didn’t get a spot of push-back when releasing the Klimax Solo 800, but that push-back was unjustified. There’s a tendency to oversimplification in audio circles (not helped by unfriendly rivalry resorting to lies). In this case, that meant “runs cool = Class D = bad!”.

This is a bit like farting in an elevator; wrong on so many levels. First, the Linn Klimax Solo 800 is not a Class D design. Second, even if it was Class D, this is not 2000 anymore and Class D has improved significantly since its early day. And third, it’s not Class D. I know just repeated the first one, but it’s such a significant bit of wrong, it’s worth repeating just in case someone is still dense enough to still think this is a Class D amplifier.

So, what we have in the Linn Klimax Solo 800 is a 27kg power amplifier that is ‘big’ by UK standards and ‘tiny’ compared to the likes of Boulder and D’Agostino. It’s also an amplifier that runs cool to the touch no matter how much punishment you choose to give it and is stable enough to just keep pumping out the power under any conditions this side of throwing rocks at the thing. But not Class D.

Linn Klimax Solo 800 silver

How did Linn make such an amplifier? OK, I’ve been a little tough on the naysayers. There are two recent errors introduced into audio amplification. The first is irrelevant here; the ‘D’ in Class D stands for ‘Digital’. The second is that a switch-mode power supply automatically means ‘Class D’. It’s a flawed syllogistic logic that was pointed out as being wrong 2,500 years before the invention of Class D amplification. Linn has been making amplifiers with switch-mode power supplies for years. Not for efficiency, low cost or even heat-dissipation reasons, but because they intrinsically move power supply noise out of the audio band. The Klimax Solo 800 power supplies have very high switching frequencies that are nowhere near the audio band.

It’s worth comparing this with a conventional linear power supply. They operate at 50Hz or 60Hz (depending on your country’s alternating current frequency). Not only can this cause transformer hum, the spectrum of noise is right in the audible range, with harmonics hitting our most sensitive frequency range, which itself causes a mild hum, this time heard as low-level noise through the loudspeakers.

Also, Linn hires a lot of extremely bright mechanical and electronics engineers and this really is a meeting of minds. Which means that chassis size is no accident, and its heatsinks create ideal thermal pathways to help cool the already cool-running amplifier circuit. It also vents through the chassis itself, from the bottom plate up to top. This is nothing new… if you are used to building skyscrapers. Some amplifiers have also adopted a similar means of cooling, but often rely on a fan to force air through the chassis. The number of audio companies that use this kind of passive cooling and do it so successfully are extremely rare.

Adaptive Bias Control

We often only think of bias in terms of balancing the output of tube/valve amplifiers. However, all Class A/B amplifiers apply a bias voltage across the output transistors to set bias current during crossover (when one set of transistors that generate the positive half of the musical waveform hands over the signal to the set that generates the negative half). This applied bias compensates for changes in temperature, voltage, current, and transistor age.

In that great empirical tradition of every scientist since Sir Francis Bacon died of pneumonia from trying to stuff a chicken with ice, Linn asked the question… is that all? The result is the company’s Adaptive Bias Control.

Adaptive Bias Control uses a digital algorithm to monitor the current flowing in the output transistors and then extract the bias from the music signal. The result is far lower distortion than an amp which operates in Class A at a higher power level. This gives the amplifier the potential to make the changeover from Class A to Class B so seamless, the only things that stop you from thinking it’s an 800W Class A amplifier is the absence of sweltering heat and a fuel bill so large you can see it from space.

Monitoring of the status of the amp is simple, and uses the roundel on the front panel. This has 100 LEDs that can be dimmed, but glow white under normal use and red when things go wrong… or so I’ve been told. Nothing went wrong. It almost unbreakable. It has a single RCA and XLR per chassis, two chonky speaker terminals, a 20A IEC input, and the power switch under the front of the amp.

Anointed audiophile

Moving out of ecosystem is a good thing for Linn, as it shows just what the company’s electronics can do when partnered to those ‘best in show’ anointed audiophile greats. Such as a pair of Wilson Audio Sasha DAWs. And that’s a fascinating exercise.

The degree of control over those speakers is immense. It doesn’t change the inherent ‘Wilsonosity’ of a pair of Sasha DAWs, but it just lays out what a lot of amp systems don’t quite get to. Sure you expect that big and expansive sound – and you get that – but with a sense of grip to the bass that gives Moving over to Francine Thirteen’s ‘Queen Mary’ has that fast percussion move from left to right perfectly with her voice and her own backing track perfectly delineated in the centre.

Go Go Penguin’s ‘Murmuration’ is a bit of modern Brit Jazz that’s usually left off the audiophile play list because it’s subtle and atmospheric, and so often played dead wrong. If the percussion and piano don’t hold together, it just sounds like noodling. Played well, it’s like a Keith Jarrett improvisation but with a full band playing together. Here, that’s precisely what it does. There’s not artifice here, and for some wanting their speakers warm, soft, spongy, a little background might need to look for something softer and milder. This is amplification that leaves you excited and breathless from all that endless information on offer.

I got into a brief sojourn through modern female artists, starting with Charlotte and the Queens, going through (in the not bad way) to Billie Eilish to Taylor Swift. ‘Billie Bossa Nova’ and ‘Anti-Hero’ by Tay-Tay are often audiophile poison; close mic’d and self-assured, they can sound peaky and ‘flubby’, or thin (because the recording itself is thin). Here, the honesty of the Linn amps doesn’t hide anything, but neither does it detract or point to a recording’s limitations.

I switched over Angus and Julia Stone’s ‘Draw Your Swords’ with its really good guitar strummed part, a piano in background, atmospheric vocals, and it’s ‘nothing added, nothing taken away’. Antipodean Americana at its best. There’s no unnecessary air, although sounds are atmospheric and wide.

Metal and Glass

Similarly, play ‘End of the Road’ by Infected Mushroom. This should sound industrial, like bits of metal and glass are being hit, but in a good way. And here it does. Often in big audio systems it just sounds large and boomy. The Linn just makes you feel the adrenalin rush.

It gives the scale and majesty to opera too. This is a telling part of tempo. Some systems tend to sound like they are racing through the music, or give it too much portent, here it’s just balance and poise. The characteristic clean, dry and detailed sound of Linn is a function of the electronics, but it’s not an imposition. It’s like the music with all the fluffy stuff taken out of the mix.

The Klimax 800 Solo lets loudspeakers do things you don’t expect. Lateralus by Tool really shows what the Klimax 800 Monos can do. That slow build from quiet squishy synth sound to full-thickness graunch is played perfectly. Everything under control, everything in reserve. It’s not bringing a gun to a knife fight… it’s bringing a tank.

More than anything, this sounds like really good, really advanced engineering in audio form. Nothing is making it sweat. Any load, any music, any volume. That’s a sure sign of that engineering is playing quietly, as the same sense of grip and control applies just as much at lower levels as it does further up the chain.

I played ‘Memphis Soul Stew’ by King Curtis through the system. You hear each musician flow perfectly together, but you can’t help but focus on Bernard Purdie’s ‘going like a train’ Purdie Shuffle. The conga often gets lost beneath this heavy mix as it’s off to the left of the stage and sometimes lost in the percussion. It’s rendered perfectly here.

Finally out came ‘The Ghetto (live)’ by Donny Hathaway. The hand claps and audience make it. They clap in a surprisingly complex sequence, and you can hear individuated sounds in the audience. It’s a great track anyway, but it becomes something so much more. And, if you carry on and play ‘You’ve Got A Friend’, you can hear the point where every woman in the audience is set on sleeping with him.

A bonus. Those cubes run cold. I gave them some bad sonic hurting. I played them to practically PA levels, to the point of wearing ear protection to see who gave in first. The amps fed such a clean sound to the speakers, they ran loud and proud (admittedly, this is one of the things Wilson loudspeakers can do… they can be given some good clean power without getting into distress), and even then it was my ears that folded first. The Klimax 800 had just been through a thorough thrashing and were cool running throughout.

Not a radiator

Downsides? There will be those who want a stereo amp instead of mono models, and it’s not hard to think there’s something coming that will satisfy their demands soon. But otherwise, unless you like the idea of your amplifier doubling up as a radiator in winter months, like the sound of your woolly existing amps, or maybe prefer the look of a specific amp that doesn’t match the Klimax, what’s not to like?

Linn wanted to plant a flag in the high-end amplifier ground. With the Klimax 800 Mono it’s done it. And it’s a huge Scottish saltire telling the high-end world to buckle up… Linn’s back and this time, it means business!