Does hi-fi end here?

kii transparent

Reports are coming in that hi-fi may, after a century of development, have actually reached its logical conclusion. It is beginning to look as though the Kii Three may be the technology beyond which it simply wouldn’t be worth going, for the vast majority of people. If so, this is quite a significant moment.

Everything up to this point has been a flawed, intermediate step.

It all started in the 19th century with the stunningly simple observation that sound is nothing more than variations of air pressure and that these can be picked up by a diaphragm and reproduced by another diaphragm. The hi-fi story has been one of how best to store the information encoded within the vibrations, and how to get the vibrations back out into the world at some time later.

First, we had purely mechanical systems which had to contend with the imbalance between the tiny amount of energy that can be picked up when making a recording versus the large amount of energy that is needed to play the recording back.

Then, with the introduction of electronics into the equation, the path towards the truly linear system was opened up. We had recording on magnetic tape, distributed to the listeners via vinyl LPs. Amplification with valves, then transistors, Class A, AB and now Class D. Horn speakers, multi-way speakers, direct radiators, acoustic suspension, and detours into panel speakers, electrostatics and even plasma. Interestingly, active crossovers are not new: they were used in cinemas in the 1930s, and there was at least one well-heeled enthusiast using them in a domestic system in the 1950s.

A major disruption occurred with the development of digital audio in the 1980s which, at a stroke, propelled performance in terms of noise, distortion and linearity to the point of practical perfection and slashed the size, weight and price of audio storage and playback equipment.

(At this point, ‘high end’ audio as a hobby left the rails and, for many, became an exercise in masochism, superstition and nostalgia).

The next part of the puzzle was solved when computing power became available. Using a computer it is possible to perform digital signal processing (DSP), allowing precise tailoring of crossovers and EQ, and for the characteristics of mechanical transducers (the speaker drivers in their boxes) to be modified.

The linear system

Now, all the pieces were in place to build a linear reproduction system using the following building blocks:

  • Digital storage of stereo or multichannel recording
  • DSP to process the signal for crossover, time alignment between drivers, driver amplitude and phase correction, EQ, woofer distortion correction using voice coil current or motion feedback
  • One DAC per driver
  • One solid state amplifier per driver
  • Loudspeaker comprising several dynamic drivers each allocated to a narrow frequency range, including sealed woofer whose bass can, if necessary, be extended using DSP EQ.

This is all perfectly realisable at low cost using physically small electronics. The advent of Class D amplification makes it even smaller and cheaper. Such a system is virtually noiseless, has extremely low levels of distortion and covers the entire human hearing frequency range.

The final part of the puzzle

There has been a lag in the acceptance of such systems even though they are spectacularly good. The recent development of a system to tackle directly the issue of the speaker’s interaction with the room at bass frequencies may be the final part of the puzzle that means these systems take off. I think the Kii Three is the first speaker to do this using DSP, followed closely behind by the huge and expensive Beolab 90.

There is some confusion over why DSP-based ‘room correction’ is needed, and what it is capable of. Although the room appears to mangle the signal terribly in terms of frequency response and phase when measured, the listener hears the direct sound from the speaker first, and an average room just adds agreeable ‘ambience’ that blends the immediate surroundings with the recording and helps to cement a convincing illusion of ‘being there’. Trying to ‘correct’ the effects of the room will make the system sound worse.

The one area where genuine problems may occur, however, is in the bass, and people attempt to solve this with DSP (not very successfully), and with room treatments (not particularly effective for the bass). The Kii Three and Beolab 90 both take the approach of using extra drivers driven by DSP to make the speaker more directional at low frequencies by cancelling out some of the almost omnidirectional bass that comes from the main driver, at the sides and rear. This effectively provides the same directionality as a huge baffle, but from a compact speaker.

Intuitively, it seems obvious that in a highly reflective, echoey room, this technique would improve the clarity of what was heard. It would also tackle problems of speaker placement near walls and corners. The amount of bass bouncing around the room is being reduced at source, rather than trying to catch it afterwards with bass traps etc. The result, apparently, is spectacularly good.

By all accounts, the Kii Three is a compact, good looking speaker with a moderate (OK, not outrageous) price, that simply disappears acoustically, leaving the music as a solid 3D image. It is loud enough and goes deep enough to satisfy the vast majority of people. No other equipment is needed other than a digital source, which could be a PC, streamer or network.

The search is, apparently, over. While it would be possible to build a bigger system, with bigger drivers, higher powered amps and so on, this would just be scaling the same fundamental design. This has already been done in the form of the Beolab 90. The system could be further scaled to provide more channels than just stereo, and more precise control of dispersion in the vertical as well as the horizontal – if anyone thought it necessary.

Conclusion

In the end, it turned out that the ‘objectivists’ were basically right: you really do just need perfect linearity to build the perfect hi-fi system (but you also have to have accuracy in the time domain, which most audio objectivists ignore).

According to reviews, and based on my own experience of not completely dissimilar DIY systems, the Kii Three is the only hi-fi system anyone will ever need. Valves, vinyl and passive crossovers seem positively quaint in comparison; ‘high tech’ passive speaker systems seem almost perverse. No doubt the Kii Three will be copied, and cheaper versions will appear, but there is no need to fundamentally change the design from now on. It should be game over for other forms of hi-fi. (It won’t be, of course!)

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10 thoughts on “Does hi-fi end here?

  1. Hi John. Very nice to hear from you. I wasn’t particularly thinking of open baffle speakers, but more these new DSP-based ones with extra drivers to provide adjustable dispersion at bass frequencies.

    I did mention the Kyron Gaia a couple of years back, as a very expensive speaker whose price ($100,000?) may obscure the fact that it is DSP that gives it its stunning sound. I think that the Kii Three is getting closer to a price and size that many people might be interested in.

    I’ll bet that most audiophiles, however, wince at the thought of DSP, thinking that it is there to ‘enhance’ the sound like a ‘hall’ setting on a home theatre amp or whatever. It takes a change of mindset to accept that DSP is doing the opposite and merely rendering the system closer to ‘neutral’. And then there are the connotations of ‘neutral’ = boring.

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    1. Do you mean the room correction technology that existed before the Kii Three? I am not convinced that it does what it is supposed to. I think that the room is not ‘incorrect’ in the first place – presumably the most ‘correct’ measurements of any audio system would be in an anechoic chamber, yet that is where it would sound worst of all!

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  2. I spent four very enjoyable hours listening to a pair of Kii THREEs on Monday at the UK distributors. I was very interested to hear how the technology actually worked out, and I guess the best compliment I can pay them is that they are completely revealing, so that some recordings are amazing, and others are, well, not to my taste! But I obviously like flat, low colouration audio… In a smallish room, they generated convincing images in realistic acoustic environments, with apparently vast resources to support large-scale events. Source was an iMac playing Tidal streams, through a Weiss Firewire-AES converter i.e. nothing especially magical. If I wasn’t before, I’d be utterly convinced of the Rational Approach now! Yes, I’d buy them, and may yet still.

    Now, of course, I’d like to hear your system :-). And you should try to hear these if you get the chance, if only as a reference point. I’m going to see if I can audition the Beoloabs now.

    I am not associated in any way with the company or distributor, just a long-time audio rationalist!

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    1. Many thanks for that – I am envious. Yes, I am looking forward to hearing them some time. You mention there were a couple of recordings you didn’t like the sound of. You can’t remember what they were, by any chance? – I’d like to try them on my system.

      (Where are you based BTW?)

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      1. As you probably know, the distributor is Purite Audio, in Muswell Hill, London, so if you’re ever that way, I’m sure he would love to demo and get your feedback, given your experience and interest.

        The recordings that were more difficult (none were truly horrible TBH) were:
        – Liede with Andreas Schiff piano, Cecilia Bartoli soprano – https://www.discogs.com/Cecilia-Bartoli-András-Schiff-The-Impatient-Lover-/release/4940396 – the vocals and piano appeared to be in two different acoustics, like the piano was close miked and the singer not so much, so the piano had an in your face quality that was impressive but not, to my ears, in the same context – like ear porn!
        – Brahms Piano Trios, https://www.discogs.com/Brahms-Nicholas-Angelich-Renaud-Capuçon-Gautier-Capuçon-Piano-Trios/release/7961956; I have this at home, so could compare; not a bad recording, just different! It sounded far too pushy, hard to listen to, cluttered, but then I turned it down considerably and the instruments dropped into the right perspective and it was all much more integrated. A dealer once told me that you have to set the volume to a level that suits the acoustic perspective, so obviously he was right!

        In contrast, stand-outs for me were
        – Schubert Liede, Johnson/Baker, Hyperion http://www.hyperion-records.co.uk/dc.asp?dc=D_CDJ33001 ; amazing!! Totally credible performance in a lovely acoustic, a real person breathing and singing. Sorry about the Schubert lied thing 😉
        – Joe Jackson, Body and Soul https://en.wikipedia.org/wiki/Body_and_Soul_(Joe_Jackson_album); recorded basically live in a NY warehouse/loft, this has a fantastic sound and acoustic, again real people doing real things.

        I also listened to more processed stuff, Who’s Next, Kate Bush, Joni Mitchell, both live and studio, but personally I find rock is fun not but realistic generally, because of the recording technique, or in the case of live, the arbitrary mix/acoustic presentation/re-record (!) involved. I enjoyed all of them, but differently from the classical.

        I live in Reading, and happy to travel anytime for the right reasons.

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  3. I listened to the Kii three’s for the first time last weekend. Just had a few songs as it was an open demonstration and I couldn’t force others to listen to ‘my music’ all the time.
    It felt like a homecoming, as if I had to search no longer. It was not spectacular, it was just ‘right’. It was just the music. I’ve been going to these demonstrations for some years now, listening to sets costing more than €100.000 and these sets never impressed me like two speakers on stands and a cd-player did this time. Still €10.000 (plus stands, plus pre-amp, I can keep my sources) is a lot for me, but for the first time I felt it could be worthwhile to upgrade my/ buy a new system.
    Incredible extra: they are small and (in the grey pro version, same price) they disappear. My wife will love that…
    I took jazz (Cécile Mc Lorin Salvant), folk (June Tabor, the Wainwright Sisters) and Americana (Los Lobos). I didn’t dare to take Lieder like John Gauk did, because most people do not like to listen to that kind of music. I should have though as I listen to Lieder a lot. I’m curious how that would sound…

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    1. Thanks for those listening impressions – I am envious that you have got to hear the Kiis.

      My impression of DSP active speakers is the same as yours: they are ‘right’ – which doesn’t mean they are ‘smooth’ or ‘easy’, but rather they are ‘full flavoured’ and a large part of their magic is the clear separation of the various voices and instruments which, if playing a recording you’ve only ever heard on a normal system, can be a startling revelation.

      There is a paradox that many people cannot get over, I think. In terms of the physical manifestation of an audio system, the olde worlde vinyl-valve-passive system looks pure, organic and full of goodness, constructed from wholesome coils of enamelled wire and finely knurled nuts. But what comes out of it is to sound as Dairylea Dunkers are to cheese. The DSP active system, on the other hand, looks as though it should produce ‘processed’ sound, but it doesn’t. In fact, it is striving to keep everything pure and natural from start to finish, free of additives and strange taints.

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      1. ‘Separation of the various voices and instruments’, that’s exactly it. For instance in June Tabor’s ‘The Dancing’ from the album Apples I could clearly hear Mark Emerson’s violin apart from Andy Cutting’s accordion, although they play the same melody. I knew it was like that, I saw them perform it live, but never heard the two so distinct in my system or any other system that I listened to.
        Pity you can’t listen to them. Guess I’m lucky living close (I go by bike) to a dealer that has them, shows them off regularly and even knows Bruno Putzeys personally. He says he considered representing only Kii, but he hasn’t taken that step (yet?). He has a lot of other fancy stuff though (and way more expensive). You can check him out: http://www.gydotron.com/

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