Krell S-1500 power amp and S-1200U AV receiver review

Oscar Wilde would have bought Krell amplification. In fact, any man whose mantra is 'I have the simplest tastes, I am always satisfied with the best' would do well to peruse the Krell catalogue for some high-end retail therapy.

I do, as a voyeur, of course, contemplate the aural merits of an Evolution 707 processor (£33,000) and seven Evolution 900 power amps (£140,000). Or, I could pay off the mortgage... Hmm choices, choices.

Krell is a brand that either needs no introduction, or lots. To those familiar with the US marque, they will respect the 30-year heritage at the high-end of audio engineering – particularly amplifiers. They will appreciate the superb build, the immaculate attention to detail and revel in the prestige of owning the brand.

To those who have not heard of Krell Industries, they may feel that £20K for the S-1200U processor and S-1500 power amp is a little rich. They might also think that anyone even contemplating spending that sort of money on an amp has a tenuous grip on reality.

You see, Krell is the Rolls Royce of the global audio industry. Like the flying lady herself, Krell simply doesn't play specification trumps with the competition. It's not pushing the boundaries of absolute power, it's not festooned with features and it won't go round corners as fast as a Lotus Elise.

Krell does its own thing in its own way and is responsible for a long and prestigious line of exquisite-sounding audiophile products stretching over three decades. It is a hi-fi brand that has status, kudos and a pride of ownership second to probably no other on the planet.

What we have here is Krell's entry into the top-end of the 'realistic' AV amplifier market, a little before the price tags move into cost-no-object territory.

The S-1200 is a fully-featured AV processor coming in at just over £10,000 in basic form and £13,000 as tested here with its 'U' suffix. This denotes the inclusion of the video upscaler grafted from the Evolution 707, offering full 1080p output and 48bit colour depth with any video input.

The processor is mated to the S-1500 power amplifier, as tested here in seven-channel guise at a smidge under £7,500.

Arthouse AV

The S-1200U is gorgeous. It works as a piece of art, its smooth lines and contrasting aluminium textures complementing the bonkers-mad volume knob with a fine sense of the surreal.

The build and finish is among the best of any amplifier to grace my listening room in 20 years of reviewing. The buttons have a firm weight, the indicator LED lights are just the right intensity and the display offers the largest and easiest-to-read text characters of any AV processor on the market.

Krell's heavyweight volume knob runs on slick bearings, meaning that a solid glancing blow will run it on for 10 or more turns. I was surprised that the knob isn't motorised so doesn't spin with volume input from the remote. While this would have been even more engineering eye-candy, perhaps Krell felt the resulting gyroscopic forces might have been a problem for your equipment rack.

Around the back is a unique selection of socketry that looks a little dated in comparison to the latest Japanese high-end receivers. Just four HDMI inputs and a solitary HDMI output doesn't impress me much, doubly so as they are only v1.3 spec rather than v1.4 – although Krell assures us that the HDMI videoboard is easily changed and designed with future upgrades in mind.

There is a positive cornucopia of analogue connections, though, including composite video, component video and even S-video sockets, totalling 11 analogue video inputs.

Nestled below these are no fewer than 10 analogue stereo audio inputs, which should cater for the most ardent audiophile. Fully-balanced XLR connections are provided as the output of choice to the S-1500, and there are enough 12V triggers and data ports to keep any system integrator happy.

Under the neatly-milled aluminium hood, the S-1200U is a little different from most processors and AVRs. Rather than use standard op-amps and integrated circuits, every channel runs on a discrete Class A circuit that Krell claims offers the greatest signal purity and the highest bandwidth.

The DSP engine is at the leading edge of the field (also grafted from the Evolution 707), based on a pair of 32bit Cirrus chipsets that feed very sexy 24bit ESS Sabre DACs. For those wishing to give the S-1200U a clean analogue audio signal and soak up some of the Krell audiophile magic, a 'preamp' mode bypasses all digital circuitry and routes analogue stereo to a balanced resistor ladder volume controller.

The remote control is yet another object of engineered beauty, assuming your aesthetic penchant airs on the side of chunky, solid and bullet-proof. Feeling as if hewn from a raw block of aluminium and filled with granite, it weighs a bit in the hand.

The buttons are small but click with the sort of clunk that would have a gaggle of car designers nodding appreciatively. It's also probably the only remote to grace my house that the dog took one look at and decided not to bother trying to chew.

Solid casework

The S-1500 is housed in a similar sized and immaculately finished case, weighing in at three times the mass of the S-1200U. Behind the smooth, clean and slightly menacing fascia, the S-1500 can be specified in five, six or, as here, seven channels of 150W – all fully balanced.

This is where Krell soars, with a huge linear power supply, massive arrays of quick-charging capacitors and high-current surface mount technology throughout. In each channel module, Class A circuitry is employed for the input stage with solid Class A/B through the power stage.

Krell is also the only manufacturer I have come across that quotes its products' maximum heat output – the S-1500 offering 1900 BTU/hr room heating as a sideline activity to first-class home cinema amplification. Green it isn't.

Connectivity to the S-1500 is XLR by choice, with phono plugs provided in case you don't have a balanced out pre-amp/processor. The binding posts certainly make for easy connection with spades or bare wire speaker cable, but the inputs and outputs are not all directly one above the other.

This is a right royal pain if you are leaning over the beast from the front to connect it up and may cause an initial connectivity mix up if you're doing the install yourself.

Connecting up

Of course, if one purchases a Rolls Royce, one would have 'a man' to drive it for you and he would probably be called the James the Chauffeur. If one purchases a Krell, one would have 'a man' to set it up for you, and he would probably be called John the Installer.

Which probably goes some way to explain why the S-1200U has a block text onscreen interface, the look and feel of which went out of date with Betamax. Compared to the current crop of even budget receivers, like Onkyo's TX-SR608, the Krell's onscreen menus are a far cry from fancy full-colour GUI's and picture-led setup screens.

The menus are a simple cascade system and are relatively straightforward where basic set-up and operation is concerned, but I do miss the onscreen explanations of what each menu feature or function does.

So when you are deep within the S-1200U's menus and are confronted with choosing what SHAPE you want your PKING filter to be, one has to refer the manual. As this is on CD rather than paper, that in itself requires you to boot up a PC to get the answer. Sigh.

There is no auto setup routine at all and the EQ system is even less user-friendly in that it assumes John has some RTA (Real Time Analyser) software on his laptop and a calibrated mic. From his measured in-room response results, he can configure a range of filter types (notch, low pass, high pass and several shelf filters) each across three individual frequency points.

There are four EQ memories, so he can save, for example, best setup for action movies, best setup for chick flicks, best setup for multichannel music, and perhaps best setup for 'posh cocktail party with Burt Bacharach background music'.

Yeah, okay, the ethos of products like the S-1200U is, of course, based on the customer service a retailer or installer brings to the party, and there is a very useful pop-up that overlays the key input signal info whenever you change modes or volume.

So why would you want to go back into the menus once it is set up anyway? It is certainly not to engage any niche features, because the S-1200U simply doesn't have any...

Think I'm joking? I'm not. Krell's combi system has no truck with networking functionality, USB inputs, compressed audio enhancers or picture fine-tuning adjustments, not to mention Audyssey DSX, THX post- processing or Dolby Pro-Logic IIz.

But if it can sound like a chorus of angels with standard off-disc HD-audio formats and CDs anyway, do we care? Er, no.

Liquid honey

Krell's audio prowess is something to behold. The S-1200U/S-1500 combination sounds huge, immersive, richly detailed, full-bodied and smoother than a panther wearing a smoking jacket.

There is none of the tizzy fireworks and in-yer-face energy of the current crop of big AV receivers, making even the best of those sound rather harsh and feisty by comparison. This is a sound to be savoured, to fall into and stay there until the film credits are rolling, the popcorn is finished and the wine glass contains nothing but a dried red ring in the bottom.

With every film there is a real presence to the audio – something you feel and experience at a subliminal level rather than simply an audible one. it envelops you and drags you into the movie with its hypnotic charms rather than projecting the sound at you.

And this in itself makes it a difficult review. I put on The Matrix (Blu-ray) as the usual opener to get a feel of this machine's credentials and made the grand total of three lines of notes before getting engrossed in the film. Suddenly two hours had slipped by.

Even with highly processed and artificial soundtracks, such as the remastered version of Minority Report (Blu-ray), the Krells elicit a naturalness that goes about as far as an amplifier can in assisting the film's suspension of disbelief.

Having spent the last two decades listening for the depth of the bass, the spatial scale of rear effects, the projection of the dialogue etc, the Krells simply refuse to be pigeon-holed with any other AV amplifier.

The bass does not attempt to turn your spleen to jelly (like Denon), high-frequency effects do not have an almost Q-Sound-like three dimensional space (like Pioneer), and the dialogue doesn't leap out of the mix to make the actors sound like they are standing beside you (like Anthem). But as a cohesive whole, the Krell sound is so very right.

The battle scenes in LOTR: Return of the King (Blu-ray) are utterly believable, placing you in the thick of the action and the emotion. With the Oliphants charging across the plains, arrows howling through the air and orc armies meeting the Riders of Rohan, the Krells show the utmost respect for this cinematic masterpiece.

It is simply massive, potent and convincing, with no one part of the sound drawing overt attention to the actual production. Likewise, dialogue benefits from the lucid and natural balance, seemingly flowing into the room. There is admirable accuracy in the placement of each character's voice, but not so that it becomes an effect in itself.

More impressive still is how this naturalness translates with music, both multichannel and stereo. Krell's heritage in the audiophile amplifier market shines out from the first disc, blending its silky smooth and even hand with detail resolution like no other AV amplifier.

Again, there are no artificial fireworks, no overtly excessive bass punch and no ear-searing top-end extension. What remains is the music, tantalisingly real and infectiously emotive. From the audio-definitive Legends of Jazz Blu-ray, Take Five by Al Jarreau and Kurt Elling oozes from the speakers like warm honey on a Summer's day, luring you in with its vocal articulation and musical sweetness.

The Krells offer amazing timing and ensure that any rhythm-based tune will get your feet tapping and head bobbing in seconds. Looking at upscaled video from a DVD you can't help but admire the clarity and edge definition created from the original SD signal – but do the results justify the £3K cost option of the 'U' suffix?

Well, not for me, but if you watch a lot of DVDs and off-air SD TV perhaps it makes more sense. Then again, does £20K for an AV amplifier make much sense to most people anyway, even if the kudos of ownership is right up there with products bearing the silver Spirit of Ecstasy?

Probably not, but hook the S1200U and S-1500 to a decent speaker system, feed it a diet of Hollywood's HD finest, and the cost seems an irrelevance in a world of utterly immersive movie and music entertainment.

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