Audio – Literature Analogy

An audio recording is a bit like a book: created through artistic or intellectual endeavour, then ‘fixed’ as a collection of pure information and distributed to customers for them to ‘consume’ in their own environments. In the case of digital audio, a recording is literally the same as a book, being stored as numbers in a file; you could store a book as a WAV, or an audio recording as a MSWORD file if you wanted.

In rendering the content to be read, there are things you could do to detract from the content of a book:

  • printed too big/too small
  • lighting too dim/too bright
  • inappropriate use of colour
  • blotchy printout
  • typeface varies with content, or randomly
  • corrupted: missing/duplicated/erroneous characters
  • peculiar paper
  • non-neutral typeface – difficult to read or inappropriate e.g. science fiction font for a Jane Austen novel
  • in the case of some ‘boutique’ printing, an appropriate analogy might be a book that spontaneously becomes too hot to touch, or occasionally ruins valuable furniture.

The emotional or intellectual force of the book would actually be reduced because of these problems. In other words, it is not true to say that the quality of reproduction doesn’t matter.

However, there is a finite envelope of neutral, even ‘mundane’, reproduction which achieves an optimal result for the reader – after reading the book they can’t tell you anything about the quality of the printing; all they remember is the content, and the content was thrilling.

Maybe the author specifies the typeface. Some books may include fine illustrations or intricate frontispieces which are intrinsic to the book. In these cases, the reproduction needs to be particularly accurate in order to do justice to what the author has created.

Beyond this, is there anything that the printer can do to enhance the appeal of the book? Well, they can create a fancy binding that the reader notices before they start reading; they can use particularly high quality paper; they can print the characters with micron precision. But only a book collector or printing technology enthusiast would care about these refinements – they have no effect on the actual experience of reading the content, and could easily detract from it.

The manufacturers of the ink and the mains cable that powers the printing press could read lots of books in their spare time, attend evening classes in English Literature, study the physiology of the eye, get diplomas in grammar, and tell us in interviews with speciality magazines about how it all informs their craft. But clearly the results would do nothing whatsoever to change the reading experience.

The printer might decide to dabble in science for the first time since they left printing college. They could do scientific trials in aspects of book reproduction where lucky participants get to read snippets of text or passages from ‘typical’ books, responding with their perceptions of differences, preferences, or even ‘emotional stimulation level’ in aspects such as:

  • typeface
  • ink
  • reading light
  • paper texture and weight
  • reading room shape/dimensions/finishes

But the results would be rather obvious and predictable, with anything slightly interesting being clearly the result of fashion, novelty and human fickleness rather than being a universal law.

The only way to actually enhance the book would be to change its content. An algorithm that replaces certain words? Re-writes sections to make them longer or shorter? Clearly in the case of literature, such a thing would be meaningless and idiotic. It is not so different in the case of audio. There is nothing but the recording: there is no technology, effect or algorithm that can meaningfully enhance it.

Conclusion

Domestic hi-fi is no more than the equivalent of rendering the printed content of a book: it can be done adequately or badly, and beyond that there is no meaningful way of improving on it. People become deluded by the idea that the rendering technology can enhance the content – which is obviously ridiculous in the case of books, but less obvious with audio.

But this is not to say that hi-fi is, in itself, boring: achieving ‘adequate’ is not trivial.

Many people are simply not used to hearing adequate reproduction regardless of how much money they spend, so they are not aware that the experience vs. quality graph has a horizontal flat top. And needless to say, the audiophile quality vs. cost graph is more-or-less random, which makes it even more confusing.

The audio enthusiast would be much happier and richer if they got a sense of proportion of what matters, then put all their creativity (and money if they’ve got nothing else to spend it on) into building the equivalent of a pleasant reading room, comfy chair and attractive bookcases rather than a solid gold and diamond reading light.

[Last edited  30/05/17]

Hi-Fi Sci-Fi

stone tape

Last night I watched a BBC TV play from 1972 called The Stone Tape. An electronics company installs its R&D department in an old mansion, with the aim of developing “a new recording medium”. Tape is, apparently, “too delicate and it loses its memory”. They stumble upon a possible ready-made solution in a room in the oldest part of the house, which seems to have a ‘ghost’ – a Victorian maid frozen in time just before she fell to her death. What if it’s not a ghost, but a ‘recording’ of an event that has somehow become embedded in the stone itself? Maybe this could be “the big one” they have been looking for…

What I particularly liked about it, was the idea that – hard to believe – there once was a time before the world went digital, and when everything was still up for grabs. Digital computers do play a role in the story, but only as a way of “correlating” the experimental results in order to spot possible connections that a human might miss.

It’s also a well-observed portrayal of life in a certain kind of company – some of it seemed very familiar.

More digital cable fun

Audiostream has another digital cable promotional article.

Within it is a little aside of a type that I often see:

<some company> is choosing to keep mum on the specifics relating to how these cable’s differing materials and construction impart different sonic flavors.

In fact no one has ever revealed the secret of how an ethernet cable (or any cable for that matter) imparts different sonic flavours – for the simple reason that it is impossible. We know it is impossible because this is a man-made, engineered system, one of whose primary purposes is to make it impossible. If, in fact, an ethernet cable physically changes the sound (as opposed to placebo effects), then this is not a digital audio system at all. It would probably be best to repair it, re-design it, or throw it away sell it to the nearest person who believes that manufacturers of audio cables “keep mum” only because they have valuable secrets to safeguard.

Digital Audio’s PR Problem

If you’d never heard of digital audio, but were told that it was now possible to store and play back audio signals on a computer, I don’t think you would raise an eyebrow. After all, how difficult can it be? An audio signal is no different from any other ‘wiggly line’ that computers seem to manipulate with ease: graphics, high quality fonts, CAD drawings, maps etc. for all intents and purposes at infinite resolution.

But somehow, digital audio is seen as a special case, where no one quite believes that it works. Looking at various forum discussions it is apparent that, in fact, it wouldn’t matter how many bits, how many MHz of sample rate, how few femtoseconds of jitter was specified, audiophiles would still be convinced they could hear the ‘1’s and ‘0’s, jitter, quantisation distortion and so on. The noise and distortion inherent in tape and vinyl that is many orders of magnitude greater gets a free pass; the noise in digital audio no matter how minuscule must always be portrayed as ear-bleedingly offensive. Why?

I think there are several reasons:

  1. Digital audio is mathematically-based. Long after real world signals have become buried in noise and distortion due to unavoidable physics, the theoretical numbers associated with the maths remain pristine and, quite unambiguously, show errors! Clearly we need better numbers. And so it goes on. In other words, no matter how high the resolution, you can always zoom in and see a theoretical error that looks just as big and clear on the screen or page.
  2. From the outset, the theory behind digital audio was discussed openly, but very few people actually understood it fully (including me). Thirty-odd years later, the misunderstandings persist. These vary from assuming that digital audio cannot know, or fill in, what is in “the gaps”, to failing to understand the significance of dither.
  3. Digital audio provided a complete mathematical solution, in many ways superior to other computer-based wiggly lines. The system is so elegant and simple that people just don’t believe it can work the way it does. [03.03.16 just saw an article that says exactly that“The intriguing aspect is that those who do understand refuse to believe”]
  4. Digital audio must always be chasing its tail, because as soon as a new performance level is achieved, it becomes possible for every Tom, Dick and Harry to buy the hardware for a small number of pounds, and even to start measuring signals at that level. Suddenly we’re all experts for whom -110dB is an average spec and must therefore be highly audible – although no one has ever heard a signal that quiet. No matter how good, digital audio will always seem mundane.
  5. Digital audio hardware is too complex to build using discrete circuitry. Integrated circuits are cheap. Audiophiles need to know they are buying better stuff than the hoi polloi, but digital audio doesn’t play the game. It remains persistently cheap enough for the masses to buy exactly the same measured performance as the most expensive fancily-boxed version of the same chip. (We are talking £30 versus £30,000, say). In the audiophile mind, this proves that measurements mean nothing and that “bits are not bits”, whereas in reality it shows the opposite.

The amazing interior world of cables

colfairy

Looking at one of thousands of ‘reviews’ of audio cables that are out there, I was struck by the vivid language that described what the reviewer had heard. I looked at a handful of other reviews and compiled a far from comprehensive list of the words and language on offer. Here is a small fraction of it:

…happier; melody; emotion; sunlight; fast; tired; cold; “mood of the musician”; languid; darker; zest; tempo; warmth; iciness; sweet; confidence; insinuation; gesture; informative; provocative; calm; assuredness; forthright; frantic; “trying too hard”; somnambulant; fire; tantalising; insightful; relaxed; refined; composed; uplifting; gravitas; nonchalant; sympathetic; magical; “unearthing the feeling and meaning”…

Audiophiles like to say that “the best cable is no cable at all” suggesting that a cable can only degrade a signal. In this light, the findings of the cable reviewers are remarkable. In order to get the signal into the cable, vibrations in the air have been converted into a different ‘domain’ – electricity – where, presumably, things could happen to the signal that cannot happen in the acoustic world. Yet the reviewers of cables don’t hear electrical, signal-degrading effects and nor do they hear ‘no effect’. What they perceive is an amazing, coherent, functioning interior world of laughter, tears, sunlight, butterflies, palaces and fairies. All this is going on inside that functional polyester braided jacket and those often-lumpy applications of heatshrink sleeving that cover a multitude of sins.

And it gets even more amazing. In audio we can change the audio signal into yet another domain: that of discrete numbers. A handy way of transmitting those numbers is electrically via cables, but what is being carried is only the numbers. Amazingly, the same magical interior worlds exist there too!

When I was very young, my dad told me that inside our Hacker valve radio there were tiny people singing and dancing. He never told me that inside the wires themselves there was a far more exciting and exotic world waiting to be discovered.

The paradox of simplicity

car-crash-2

A constant refrain in audiophile circles is “the simpler the better”. Once beyond what audiophiles dismiss as ‘mid-fi’ then the more expensive the equipment, the ‘simpler’ it generally is. It is very intuitive of course: the fragile signal is making its way from A to B; each wire, connection or device in the way is supposedly corrupting the signal. Active devices become a necessary evil, as they are not inherently linear and generate excess noise, semiconductors being the worst of all. Transformers are worthy of veneration because they are passive but possess magical properties of being able to change a signal’s voltage or current up or down.

Some audiophiles dream of an amplifier comprising a wooden box with a single glowing valve on top (preferably one of those slightly bulbous ones) and a Bakelite volume control based on a rotary switch with three settings. Underneath, the wiring is ‘point-to-point’ because this provides the shortest signal path. The wire is unbleached cotton covered – it’s the simplest and most natural kind. The output goes off to a single driver horn speaker via some knurled terminals.

Contrary to this, I think that the impression most ‘lay people’ would have of vintage technology is the correct one: the ‘simplest’ systems sound horrible. It is the sound of distortion and strange frequency responses. It is the reason why the rational engineers of the past moved towards more complex hardware (and now software). The result was the sound that grabbed your attention in 1973, perhaps, when you heard your first proper stereo. It is the sound that audiophiles now want to sacrifice on the altar of ‘simplicity’ while divesting themselves of huge quantities of cash.

If only they would realise that the intermediate electrical signal is only a small part of the overall system and not an end in itself. It must be conditioned for its emergence back into the acoustic world via the medium of electromechanical transducers, meaning that the ‘simplest’ hardware renders the overall acoustic signal most susceptible to complex distortions. Audiophiles should stop thinking about what is happening in the circuitry at such a low, folk-intuitive level. What matters is the system’s overall ‘transfer function’ from input to output. It is a case of prioritising the various distortions and dealing with them sensibly.

Conventional non-minimal hi-fi systems are half way to the goal of a neutral transfer function. They provide enough power at low distortion levels to overcome the inefficiencies of direct-radiating drivers (which provide the most uncoloured acoustic output) and they cope with the fact that the signal needs to be split into several frequency bands in order to suit multiple drivers of the appropriate sizes. However, on an oscilloscope screen, what comes out of the speaker does not resemble what the microphone picked up. The standard-issue hi-fi system plays fast and loose with phase and timing because of the effects of the crossover filters and the phase shifts of the drivers themselves. The amplifier is unable to control the cones accurately because of power-wasting passive components in the way. But this is all supposedly acceptable, because we have reached the ‘sticking point’ for audiophiles in terms of the complexity they are prepared to countenance.

Active speakers double or triple the number of amplifiers in the system. This is perceived as a vast step up in complexity, and so active speakers are rare in the world of audiophilia. A further abomination for most audiophiles, but the only practical way to correct the phase and timing errors, is DSP which involves digitising the audio, performing calculations upon it, and then re-converting it back into analogue form. It can also replace chunks of electronic hardware by performing the function of crossover and EQ far more accurately than the analogue alternative. The folk-intuitive view of this is disastrous! The precious, pure, sinuous signal is replaced by hard, discrete numbers. The calculations performed on them are non-audiophile grade – indistinguishable from the same calculations performed in mobile phones and electronic doorbells – and the chips are made of plastic not Bakelite.

The truth, of course, is that digital audio is hardware-agnostic and unbelievably accurate. If audiophiles could just stop thinking in terms of the nuts and bolts, they would realise that such a system, although unimaginably complex internally, is the simplest system of all.

The agony of the audiophile

will o the wisp colour

[Josef Lebovic Gallery]

An article  highlights why it’s a bad idea to become obsessed with a hobby based on wills-o’-the-wisp. On the surface, the mishaps that befall the author cost him a great deal of anxiety and a few thousand dollars – obscured by the fact that he “takes advantage” of the situation and ‘upgrades’ his wrecked cartridge – but the biggest mistake that audiophiles make is to fall down the rabbit hole that is ‘high end’ audio in the first place. Maybe we’ve all been there: worrying that our cartridge isn’t set up properly, prompting us to carry 70lbs of hardware out to the car and drive for five hours to have a specialist lay their healing hands on it. I might have found myself somewhere on that crazy continuum at one time. Not any more.

‘High end’ audio is a particularly unhealthy obsession, I think. From my perspective, the whole thing is like the emperor’s new clothes. I don’t think of it as a cynical con; rather that the putative experts, manufacturers and customers are all prey to the same confusion, superstition, and self-defeating psychology.

I think that listening to equipment (as in ‘listening tests’), rather than listening to music, changes our perception of it: it is necessary to ‘let go’ of the equipment in order to enjoy the music. The placebo effect, both positive and negative, means that there is no consistent audible effect perceived when consciously chopping and changing audio components. Thus an audiophile whose philosophy is based entirely on his golden ears has no anchoring point, and must float forever in audiophile space. He will drift helplessly towards every passing audiophile fad, hearing “night and day” differences when, in fact, no measurable or audible change has occurred. This is how we arrive at the 70lb turntable and the £10,000 piece of wire lifted off the floor with ceramic pots that cost more than my entire system. We are talking real money.

In all other respects these audiophiles are probably sensible, grounded, intelligent individuals who would not normally fall for what passes as slick advertising or the verbiage of wannabe ‘high end’ ‘designers’. They would not normally splash multiple thousands of pounds on something made, effectively, in a garage by a hobbyist. But they do it with audio. The image of people sacrificing their real lives – houses, cars, holidays, retirement – on electronic wills-o’-the-wisp is a source of fascination to me.

Bring back the projectionist?

film

An article in today’s Telegraph makes a plea for cinemas to start showing film again, rather than the digital version they are solely equipped to show now.

To me, it seems just the same as the digital/analogue argument that rages in hi-fi. We have the same ‘sighted’ comparisons that of course confirm the simple folk-association of digital = soulless and artificial, resulting in the implication that true auteurs must always insist on the pain and expense of film because it is ‘real’, organic etc.

I don’t buy it. I think that, as in analogue audio, people are superstitious about the medium that produced great art in the past, wanting to believe there are spirits trapped within it that will help them to do the same thing today. As with vinyl, film technology is amenable to being crafted by “artisans”, old-school technicians and operatives in brown coats, and is simple enough for ordinary people to understand. They remember it from their pasts. This qualifies it to be ‘The People’s Technology’ and it is easy to see how a ‘movement’ could be started to push for the revival of analogue film.

All good fun, except that from then on, the superior digital option becomes second class in people’s minds: the experience of seeing the film in digital form is tarnished even though that is how most people will see it. A new premium price can be charged to see the film in ‘analogue’, and people who do this have their expectations confirmed, of course. The person with the huge OLED television who, really, could have had a pretty good cinema experience at home, has that pleasure taken away from him – just as the vinyl ‘movement’ has taken the pleasure of listening to audio perfection away from the only people who might care about it. In other words, by falling for these ‘revivals’, people sabotage their own experiences. Audiophiles could have enjoyed digital audio forever, but now most of them believe that it is a second class experience compared to vinyl. They either get on the rack of pain and expense – knowing that to even play a precious record damages it – or live with the regrets about what might have been. This is pure psychology.

And of course money is diverted from the further development of digital technology to be spent on this technological nostalgia trip.

I used to do my own photographic processing when I was young. There is nothing that would persuade me to do it again. I see no weakness in the digitally-derived prints that are produced these days. Scans of old slides and negatives seem to capture their essence perfectly well, and the modern high resolution cameras that we all have are superb. People forget how terrible most photographic efforts used to be, and how poor most cinemas were in terms of their projection.

The Power of Ideas… to enrage audiophiles

I just had a somewhat abrasive online encounter. I had the temerity to comment on some blog articles about digital cables and found that what I was saying seemed to send people apoplectic with rage.

treknorman

Basically, I asked: if digital cables are responsible for changing the sound in any way, then how could high quality online streaming services work at all? The signals are sent over long distances of dubious cable, non-audiophile optical fibres and satellites not even made of silver, and yet, supposedly (and actually), the signals emerge in real time, utterly perfect – except, that is, for the deleterious effects of that pesky final cable…

As always with this sort of idea or thought-experiment, I was told I was “missing the point” – the articles were primarily about cables’ effects on noise injection, hum loops, jitter and so on, so such “philosophical” arguments were irrelevant, they blustered.

But if we accept the notion that high quality online streaming is possible (audiophiles have no trouble accepting that TIDAL is “CD quality”), and that it is independent of the types of cables in the global internet (changing dynamically from moment to moment), and indeed is indistinguishable at the DAC from a network-based CD drive (for example) on our local network, then the implication of the ‘noise’ agenda must be that all the ‘noise’ from the thousands of miles of bog-standard cable and bog-standard digital gubbins along the way can be removed before it even reaches our network. So why can the DAC not incorporate this 100% noise blocking function itself? If it can (and it can) then the final cable in the chain takes on only the same significance as any other of the myriad cheap, long cables in the chain i.e. demonstrably none whatsoever. And, indeed, that was the whole idea of digital audio in the first place – an idea that has somehow become forgotten along the way.

Of course I accept that some digital audio implementations are poorly-designed and could, indeed, be susceptible to noise injection, hum loops and so on. Some may even suffer from power supply noise related to the digital signal and “how hard the chips have to work”. But if so, then messing around with cables is a red herring; trying to fix a fundamental problem with a sticking plaster. But even this overstates the case: at least a sticking plaster is designed by clever people who understand the problem. It is effective at what it does and doesn’t pretend to work simply because it is made of a certain material or incorporates an ancient Celtic weave. A common mistake is to believe that audiophile hardware is ‘higher quality’ than standard, but that rationalists don’t believe it is worth using. No. The truth is that rationalists don’t even believe that it is ‘higher quality’. Probably the opposite. It may be more expensive. It may use materials that are sacred to audiophiles. But it is just a manifestation of ignorance and magical thinking, and is worthless or worse. A more expensive cable can/will not fix the problems with your defective DAC. The only way to fix the problem for real is to design the electronics competently, and to design the last digital node to block ‘noise’ in the same way as earlier nodes can, apparently, block all the noise of the entire internet.

The unpalatable truth is that if you hear differences in your system when you change your digital cables you are either:

  1. imagining it, or
  2. the owner of hardware that is defective (by design).

I would bet that (1) is the more common. Given a suitable measurement setup whose resolution equalled or exceeded the resolution of your audio DAC, you could verify your system’s immunity by feeding in known digital test waveforms and checking that what came out of the DAC was always the same regardless of cable and any other upstream hardware. This idea, too, was met with seething fury!

Maybe I have realised something: many people simply cannot process “philosophical” ideas. The only way they can get a handle on them is for someone first to ‘downsample’ them into a form they are comfortable with:

  • brand names and products
  • industry gossip and hero-worship
  • low level engineering trivialities as a substitute and/or smokescreen for genuine ideas
  • shop-floor nuts and bolts

But this is a lossy process. It is impossible to ‘upsample’ the low level tittle tattle back into the world of ideas. Any attempt to do so, or a refusal to ‘downsample’ in the first place, causes panic, abuse, then meltdown.

Words that describe audio

An article on Audiophile Review talks about a research project whose aim is to find the best words, or categories, with which to describe and quantify audio performance. In the end they come up with just three: “timbre”, “space” and “defects”.

At face value, it strikes me that this is two words too many. Wouldn’t it be simpler to forget “timbre” and “space” and simply list the “defects”?

The answer is that this list shows that audiophiles do not believe that there is an unambiguous correctness (or neutrality) that a system can aspire to. They think that a good audio system adds its own character to the recording and that one chooses it just as one would choose a violin, fine wine or work of art. This character, or musicality, may be specified in terms of timbre and space and is independent of any defects.

If only there was a word to describe this aspect of audio. It is analogous to anthropomorphisation i.e. the attribution of human motivation to inanimate objects and animals. In this case it is the attribution of the characteristics of musicians, music and musical instruments to electronic hardware. Something has gone seriously awry. People fully understand that a television set should be as neutral as possible in order to experience art, performance and culture through it. I think they used to understand this about hi-fi (hence the name) but not any more.