Category Archives: audio

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AVI preparing a successor to the ADM 9.1 – the floorstanding ADM 40

AVI is a small British hi-fi manufacturer who advocate active loudspeakers; its AVI 9.1 (recently lightly revised as the AVI 9T) is widely liked for its clean uncoloured sound and lack of clutter – all you need is a digital source. However the 9T lacks grunt and until now the recommended solution has been the companion subwoofer, which adds a substantial £800 to the cost. The 9T is £1125 so that is not far short of £2000 for the pair, making the value for money less impressive.

Now the company is preparing an all-in-one successor to the 9.1 – the floorstanding, 3-way active ADM 40. From what we know so far:

750 watt per-channel RMS amplification
3-way active crossover
8 inputs
Remote control

It will be possible to fine-tune the bass via the remote control; there will also be a companion iPhone app.

How much? According to AVI man Ashley James “under £3000 definitely, hopefully £2500”.

Hitherto AVI has been opposed to full-range loudspeakers, claiming that smaller two-way loudspeakers supplemented by a subwoofer is a better solution. Why the change of heart?

We don’t like typical three way lower crossovers because they are in the middle of the most music. Even  phase perfect ones are still reversing it and back again!!

However we’ve found that you get 95% of the intermod reduction by crossing over at 100 Hhz, a noticeable increase in clarity and dynamic range and the bass can be adjusted to suit rooms and program material, in this instance by remote, which isn’t possible with an old fashioned three way. And there’s an LFE input, so it’s a win win situation in a comparatively small speaker because we can use a Sub driver and not one for a three way.

says James.

On the face of it the ADM 40 will be better value than the ADM 9T plus subwoofer, as well as more convenient; one fewer box has to be a good thing. Then again, can AVI really deliver something as good as the 9T but with full range? The proof will be in the hearing.

There is a review of the ADM 9.1, similar to the 9T, here.

Update – oh dear:

We can’t get the performance from a floor stander and they cost disproportionately more for limited demand, so we’ve dropped the idea.

seems to be the latest news.

Surround sound 5.1 headphones–why and why not. Roccat Kave reviewed

There is something counter-intuitive about 5.1 headphones. Headphones just look so stereo. Can you really create the surround sound illusion with the speakers so close to the ears?

It turns out you can, or at least sufficiently so to make these Kave 5.1 headphones from Roccat a satisfying product. They are intended primarily as gaming headphones, which explains the attached microphone, though it could be handy for Skype calls and other such uses as well. Another common use is for movies, where surround sound adds to the drama and sense of immersion. They are not really intended for music; but I found them pretty good for that as well.

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What you get is a set of closed-back headphones with a relatively fat cable and an inline control box. The cable has four two-channel mini-jacks, one each for front pair, center and subwoofer, read pair, and microphone input, as well as a USB connector which supplies power and enables communication between the control box and the PC. You can flip open a panel on the control box to reveal channel sliders and to switch between “game” and “movies”.

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Installation is a matter of plugging the cables into your sound card and a USB port. You need a 5.1 sound card, since there is no decoder in the Kave. Another point of interest: the volume control and mute on the control box directly control the volume and mute on the PC, but the 5.1 balance controls operate on the signal after it is received from the sound care; at least, that is what I observed on my test system.

The plugs are colour-coded; I also found the Windows 7 5.1 configuration utility handy for checking that I had the connections right.

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There is a CD in the box but it does not contain any drivers as none is necessary. It does have a 5.1 demo video and a manual.

I tried the Kave with a variety of game, movie and music DVDs. In general I was impressed; but it is important to set expectations. I am a fan of Sennheiser headphones and use the high-end HD600 as well as a variety of cheaper sets. In comparison with the Sennheiser models the Kave is enjoyable but unrefined, and for listening in stereo a traditional set of headphones is probably what you want.

Equally, if you have a full home cinema setup and sit in the sweet spot with carefully-positioned loudspeakers and a proper sub, the Kave cannot compete favourably.

The point though is that such a setup is both expensive and often impractical; sometimes you need to listen privately or in another room.

In this context, and given a 5.1 mix, the Kave has real advantages, even for music. It is curious. I played with the sliders to compare the sound of the front and rear channels, and found that the positional difference is subtle and hard to detect. If you play a 5.1 mix with the Kave though, and then play the same downmixed to stereo, the sound is flat in comparison, in ways that even the purer hi-fi sound of something like the HD600 cannot altogether compensate for.

The benefit of true 5.1 sound is sometimes apparent in details that you can more easily hear, and sometimes a matter of a more three-dimensional sound.

The sub in the Kave is puny compared to a real one, but does add some grunt to games and movies. Confusingly, Rokkat also calls this a “Vibration unit” which lets them say that the Kave has “adjustable vibration” – all this means is that you can vary the level of the sub channel as you would expect. There is no additional vibration unit.

It is a compromise, and if possible you should try to hear the Kave in comparison with a high quality stereo set before making a decision; or ideally have both so that you can choose the best option for a particular title.

The Kave is on the heavy side but comfortable to wear. It has a blue neon light at the headphone end of the microphone stalk, and another which lights up when the microphone is muted; this is meant to look stylish and futuristic though will not appeal if your tastes are more towards the understated.

The Kave folds for convenience though it is hardly worth it as they are still somewhat bulky. The multiple connections and awkward control box make the Kave best suited for semi-permanent installation in a desktop PC, rather than something you would use on your travels.

Given its suitability for gaming, it is a shame that the Kave cannot be used easily with an Xbox 360 or PS3, though with adaptors you should be able to get it working, remote volume aside. It should work fine with a Mac though, if you have a suitable soundcard.

I do not mean to be negative. I was pleased with the Kave, which offers an excellent listening experience, recommended for games for movies and enjoyable for music as well.

Summary

Good points: Comfortable headphones that offer a taste of real 5.1 sound; well made and high quality.

Bad points: Multiple connections and floating control box can be inconvenient.

Summary: Real 5.1 sound headphones and most enjoyable, though less refined than stereo sets at a similar price level.

Spotify everywhere: now on Logitech Squeezebox as well as Sonos, Smartphones

Spotify, the music streaming service, has announced a partnership with Logitech to enable subscribers to play music via Squeezebox. Logitech already has a partnership with Napster for a similar service, but Spotify is winning in terms of usability, ubiquity and mind share.

It follows a similar agreement last September between Spotify and Sonos, a Squeezbox rival. The company has also announced support for Windows Phone 7, which joins Apple iPhone/iPad, Google Android, and Nokia Symbian among supported smartphones.

Spotify is available for free on a PC or Mac, but supported by advertising, making it like a commercial radio station where you choose the music. However only paying subscribers get the benefit of using the service from these other platforms.

In my view streaming is the future of mainstream music distribution, so I see this as significant. Why pay for downloads, when you can choose from a vast catalogue and play what you want when you want?

The main snag with Spotify is that some artists are not available on the service, and some countries (including the USA) cannot get Spotify. Still, if it builds a big enough customer base, the music industry may find it cannot do without the service.

How to get better sound: higher resolution, or something else?

A topic of enduring interest for me is the audible benefit (or otherwise) of high-resolution audio such as SACD, the near-obsolete DVD Audio, or increasingly downloads offered in 24-bit/96 kHz or better resolution, versus the 16/44 resolution of CD, also known as “redbook” because this part of the CD’s specification was defined in a red book.

I wrote a piece on this last year, which is still among the most-read articles on this web site, so I am not the only one.

Today I came across some old articles by Dave Moulton which I enjoyed. He is an audio engineer who has also worked on the subjective measurement of audio systems – in other words, if you are a maker of audio equipment you can go to him and say, “this new feature of ours, does it really make a difference or sound better?”

Moulton wrote a series of pieces starting here which examine the human aspect of audio technology. One of them explains why we exaggerate small differences. He is also, as I suppose I am, sceptical about the benefits of high resolution audio:

… the resolution benefits of 20-bit and 24-bit signals are not only hard to hear, they’re, well, inaudible as we currently do it. Uh-oh!

and I like his awareness of the “system” – not just the equipment in our living rooms, but the entire chain:

When we have a SYSTEM with really smooth response (say, +/- .5 dB) from 30 Hz. to 17 kHz., from microphone diaphragm to eardrum, well, then we really have something to brag about. And UNTIL we can do this, it doesn’t do a lot of good to invest a lot of bucks in dramatically extending the response of a single stage.

Another series of articles is specifically on high resolution audio.

Of course high-resolution is valuable for mixing, mastering and audio processing, where there is a danger of cumulative error; and I accept that there could be cases where there is some small benefit in high-resolution playback equipment. That said, this is a much-misunderstood area; and audio vendors are happy to exploit our natural instinct to believe that bigger numbers must mean better sound.

I still see people drawing sound curves with steps in them to show that increasing the sample rate must improve the accuracy of the curves – when it has been shown that this is not the way digital audio works. There are some excellent papers here (click the link for Support) by Dan Lavry of Lavry Engineering, makers of high-end digital audio converters, which explain the mathematics:

Let us review Nyquist Sampling Theory: A sampled waveforms contains ALL the information without any distortions, when the sampling rate exceeds twice the highest frequency contained by the sampled waveform. Note that once we agree on what constitutes audio bandwidth, we need not sample much faster than twice that bandwidth to have the ability to retrieve 100% of the original signal.

Despite my high-res scepticism, I am still keen on getting the best sound I can afford at home. In fact, this is why it is important to have this debate. We need to know what it is worth spending money on.

In the end, it makes sense to invest in differences that you can easily hear, such as those between loudspeakers, rather than in differences that are subtle to the point where you can debate whether they are audible at all.

Review: Audyssey iPhone Audio Dock South of Market Edition

How good can a dock for an Apple iPod or iPhone sound? Pretty good, as this high-end South of Market Audio Dock from Audyssey demonstrates. If you think all iPod docks have thin, tinny bass, think again. It also turns out to be a neat speakerphone.

The dock has a distinctive bulbous shape, measuring around 24cm (9.5”) square on its largest side, with the dock mounted on the front edge. The unit is designed to sit on a desk or table and is surprisingly heavy for its size – probably an encouraging sign. Viewed from the front it looks tall and compact.

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The side view though shows that the speakers do have some room to breathe.

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As you can see, the speakers are firing more or less sideways. This is not ideal for stereo imaging, but in practice the dock delivers a wider image than you might expect.

Here is what you get out of the box: the dock, a remote with a battery, a USB cable, and two 3.5mm audio cables.

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Getting started is just a matter of putting the battery in the remote (slightly fiddly), plugging in the power cable, docking your iPod or iPhone, and playing some music. There is also an app you can download that provides some additional settings.

Before going into more detail about what this dock is capable of, let me say immediately that the sound quality is excellent. Words that come to mind are crisp, deep, rich, smooth and powerful. Vocals have real presence. The dock successfully conveyed the drama of a Mahler symphony, the growl of Tom Waits, the complex rhythms and pace of Santana, and the tender emotion of English folk singer Sandy Denny. Once I started playing music, I did not want to stop.

The secret of this high quality is twofold. First, the electronics follows high-end principles. There are four speakers – two 4-inch woofers, two .75 inch tweeters – which are powered by four separate amplifiers controlled by an active crossover. By contrast, a typical home hi-fi would have two amplifiers driving speakers with passive crossovers. Active crossovers mean that the musical signal is divided into the optimum frequencies for each speaker driver at a low level, introducing less distortion and improving control.

Audyssey takes further advantage of this, by using software processing to mitigate the limitations of the speaker drivers. That’s no surprise, since Audyssey specialises in audio processing technology for other manufacturers, which gets incorporated into home theatre and in-car equipment.

According to the specification, there are several techniques implemented in this dock. BassXT extends the bass response by boosting the signal dynamically to flatten the frequency response at a point when it would normally be dropping off. Audyssey EQ corrects “time and frequency response” imperfections introduced by the loudspeakers and cabinets. Dynamic EQ performs frequency response correction to preserve a flat response as volume changes. Dynamic Volume evens out the volume level to compensate for differences in the volume of the source.

Some of these features can be controlled or disabled by a companion iOS app, free to install. Specifically, you can disable Dynamic Volume or set it to optimize for Background Listening; you can apply tone controls including a single tone control called Tilt or traditional bass and treble; or you can set your own custom EQ.

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I admit that seems a lot of processing; and it would not have surprised me if the results were worse than pure straight-through audio reproduction. That is not the case though; the unit sounds very good indeed. Given the challenge of getting high quality sound from a relatively small enclosure, taking advantage of digital processing makes sense to me, provided it is carefully implemented at it is here.

Controlling playback

Once you have docked an iPhone and set it playing, you can control it either from the iPhone itself, or from the supplied remote, or pause and play by tapping an illuminated icon on top of the unit (It is not obvious that this is a button, but once you discover it, it is a handy feature; it also has some other functions including answering phone calls and showing Bluetooth status).

The remote has buttons for volume up/down, pause/play, and skip forward or back.

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The Audyssey dock supports Bluetooth and for full features you should pair your iPhone with it and keep Bluetooth on. Now you can stream music from an iPhone even when it is not docked. This can be handy, since the iPhone is easier to use in your hand then when docked. Using Bluetooth, you can undock it with only brief interruption in playback, for example for selecting music. Range seems good, and I was able to detach the iPhone, walk through the door of my study and into the corridor, and the music kept playing – though note that the audio quality will not be as good. I found the quality acceptable though noticeably inferior.

When docked, the iPhone will charge provided the dock is not in standby mode.

There are also buttons on the remote intended for the dock’s speakerphone feature, which deserves its own paragraph.

Audyssey as conferencing speakerphone

The most intriguing feature of the Audyssey South of Market dock is its speakerphone feature. For this to work, you must have Bluetooth enabled.

Scenario: you are enjoying music, when a call comes in. At this point the music pauses, the iPhone invites you to decline or answer the call, and a ring sounds through the dock’s loudspeakers. Tap the phone icon on the remote and you can answer the call while using the dock as a speakerphone.

It turns out the Audyssey dock makes a rather good speakerphone. It performs microphone array processing and echo cancellation to improve voice quality, using front and rear microphones, and in my testing this worked well.

You can also wire up the dock to a computer, using its line in and mic out connections. This lets you use it as a speakerphone with Skype or other Voice over IP providers. Nice idea, though my guess it that this is too inconvenient for most users. Working with the iPhone is more compelling.

Connections

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This is the back panel, showing the microphone output, line in, and USB port. Above the panel is a button for pairing a Bluetooth device. If you connect the USB port to a computer, the docked iPhone will sync with iTunes, though auto-sync can be a nuisance if you frequently dock and undock the device.

Annoyances

Not that many. However, I would like some way to select music from my seat when the iPhone is docked, beyond the simple track skip on the remote. Of course you can do this using Bluetooth streaming, though sound quality may be compromised.

Even with Bluetooth set up, I find that removing the iPhone from the dock pauses the music. I have to tap play to resume it. Re-docking the iPhone interrupts the music briefly but it resumes automatically.

Considering the cost of the device though, it’s a shame that Audyssey does not supply a proper manual; there is an excellent one online [pdf], but the one in the box is just safety warnings and limited warranty, pleasing for the lawyers but not for users.

The stereo separation is good considering it is a single box, but poor compared to two speakers set apart in the normal way.

Summary

The Audyssey South of Market Dock costs more than most iPod/iPhone docks, but in return it delivers superb sound quality along with some well thought-out speakerphone features.

The B&W Zeppelin makes an interesting comparison. The Zeppelin is a little more expensive but has better stereo separation thanks to its 640mm (25.2 in) width, and has a sub-woofer for extended bass. On the other hand, the Audyssey is more compact and could be considered less intrusive depending on what you think of the Zeppelin’s distinctive styling, and the Zeppelin has no Bluetooth streaming.

In the USA it is an easy decision. The Audyssey dock at around $400 is better value than a Zeppelin at around $600. In the UK the fact that B&W is a UK company whereas Audyssey is based in Los Angeles seems to bring the prices closer together: £400 for a Zeppelin versus £350 for the Audyssey dock. Try to hear them both; but the Audyssey dock is not shamed and is still well worth considering.

Compatibility

The South of Market Audio Dock fits:

  • iPhone 4
  • iPhone 3 and 3GS
  • iPod Touch
  • iPod Nano (4th and 5th generation)
  • iPod classic

Price and availability

The Audyssey South of Market Dock costs around $399.00. You should find it at Apple stores among other retailers.

Amazon.co.uk is advertising this dock for availability from 15th January 2011, at £349.99

 

SHM-SACD – super-expensive, but how super is the sound?

The problems facing the music industry are well-known: the CD market is fast disappearing thanks to digital downloads, both legal and illegal, and income gained from downloads does not look likely to match that lost from CD. But what about the niche market for recordings of superior quality? Universal Music Japan has come up with a product that combines several ideas. The first is SHM, or Super High Material, first used for CDs with the claim that, despite being a digital medium, players would extract better quality sound from CDs made with it. The next theory is that the high-resolution SACD format will play back more accurately if the disk only includes a stereo layer, rather than including stereo, multi-channel, and standard CD layers. The result is a new SHM-SACD series, remasters of classic titles at premium prices.

The source used for these titles varies. Some are new DSD (Direct Stream Digital, the digital format of SACD) master made from copy master tapes held in Japan. Some are re-issues of existing DSD transfers. Some are newly mastered from original master tapes.

Who’s Next is apparently in this last group, newly mastered from the original tapes. It is said to have been done as straight as possible,  with no equalization or compression, and is the original mix.

This is a favourite of mine, so I bought a copy. It comes in typically over-the-top Japanese packaging, SHM-SACD in a plastic film sleeve inside a paper sleeve inside a card sleeve. There is a fold-out cover with a photograph I’ve not seen before, liner notes, obi, and a card to return with suggestions for future titles.

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I played the disk and compared it to my existing CD. In fact, I must confess, I have several copies. Who’s Next has been issued many times, and the most obsessive fans know that the best CD is an early one mastered by Steve Hoffman and made in Japan for the US market. He has written about how he mastered it on his forum, using as little processing as possible though he did add some modest EQ.

Both the Hoffman CD and the new SACD sound very good. I am not quite sure which I prefer, but it may be the SACD which sounds exceptionally clean and lets you easily follow John Entwistle’s fantastic bass lines. Or it might be the Hoffman CD which is remarkably crisp and muscular. There is an odd problem with the SACD, which is that the last track is noticeably louder than the others. It was recorded separately, but that seems no reason not to match the volume.

So do I recommend the SACD, and by extension, the new SHM-SACD range? Well, I am all in favour of mastering CDs with full dynamic range, no attempt at noise reduction, minimal processing, and without the excessive compression that mars so many new releases. The Who’s Next title shows what great results you an get with this approach.

That said, it is tragic to have these high quality new remasters restricted to a niche format at an excessive price. The SHM thing I suspect is nonsense; if CDs and SACDs made with ordinary material did not work properly, we would have noticed it years ago. The advantages of SACD are doubtful too, certainly for stereo, because the limitations of human hearing make the extended frequency response pointless. I have researched this to the best of my ability and while I don’t know for sure that high-resolution formats like SACD are completely pointless, it does seem that standard CDs can sound either the same or nearly the same when the audible difference is put to the test with any rigour.

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The SACD format is also rather inconvenient. You cannot easily rip to to a music server, you have to make a further digital copy from the analogue output of the SACD player, and then rip the copy, probably breaching your license in doing so, and potentially degrading the sound quality.

I also compared stereo-only and hybrid SACDs using Bob Dylan’s Blonde on Blonde, which was issued in both guises. The stereo version sounds identical.

Still, even you are paying for a certain amount of stuff and nonsense, you are also getting SACDs that genuinely sound good, at least in the case of Who’s Next. Perhaps it could even be worth it.

Peter Gabriel’s high-res music bargain with scratch my back

Peter Gabriel’s Scratch my Back is an intriguing release – an album of cover versions of pop and rock songs, but with an orchestral backing. It actually works, once you set your expectations accordingly.

The thing I want to draw attention though is a remarkable offer that comes with the deluxe version of the CD (worth it anyway for Waterloo Sunset, otherwise unavailable). You get a code with it that buys a three month trial of membership at the Bower & Wilkins Society of Sound site. The details are here:

The stunning super-high quality version of Peter Gabriel’s new album ‘Scratch My Back’ is available now from Society of Sound as a 24-bit FLAC download.

If you have bought an enhanced CD you will have a voucher code entitling you to download the album from us as well as giving you three months full membership. If you don’t own the album you can subscribe for six or twelve months to access it.

This means you get not only the high-res version of Scratch my Back (without Waterloo Sunset, unfortunately), but also “any past albums of the month” on Society of Sound, many of which are also in 24-bit FLAC. I counted 19 albums in all, with artists including David Rhodes, Ennio Morricone, Speed Caravan, Brett Anderson, Charlie Winston, Gwyneth Herbert, Tom Kerstens, Skip McDonald, and the Portico Quartet.

I’ve been working through them and enjoying what I hear.

This still begs the question, of course, of whether hi-res is audibly any different from standard CD quality. If this is a question that interests you, as it does me, then you get plenty of material to experiment with. In addition, the overall standard of the recording quality found here seems excellent.

AVI ADM 9.1 loudspeaker review – should we all go active?

I have reviewed the AVI ADM 9.1 active speaker system. This is a distinctive system, in that it builds amplification – both pre- and power amps – and a DAC into the loudspeaker cabinets. There is a remote to control volume and to select between two digital inputs or an analog input.

Why distinctive? Well, most consumer hi-fi is based on passive speakers with an external amplifier. There are lots of active monitors on the market aimed at the professional audio engineer, but most of these lack the pre-amp, DAC and remote.

What is an active speaker? Read the review; but in a nutshell it is one where each speaker driver has a dedicated amplifier, so that the crossover, which divides the audio signal into frequencies suitable for each driver, works on a low-level signal rather than one that is already amplified. This is well-known to reduce distortion. It also means that the amplifiers can be tailored exactly to the characteristics of the speaker drivers, since they are the only ones they ever have to drive.

The ADM 9.1 is expensive, but less so than the very high-end active systems on the market from the likes of Naim and Bang and Olufsen.

It raises the question: why are there not more active systems in consumer hi-fi? The short answer is that they do not sell that well, because they are inherently more expensive – you need at least double the number of amplifiers, presuming a two-way loudspeaker.

The long answer, claimed by AVI, is that the hi-fi industry is wedded to the idea of an upgrade cycle that keeps customers buying more. Passive systems, with several separate boxes, are more amenable to that process.

CDs to downloads: the noose tightens

I’ve just received my copy of David Bowie’s A Reality Tour, a double CD for which I paid £11.98 from Amazon.co.uk – though if I’d waited a few days, I would have been able to buy a US import for £8.59 including shipping, at today’s prices.

For my money I get a tri-fold package with photos from the tour, and a 12-page booklet with more photos and credits.

The CDs between them have 33 tracks – not bad value.

Still, I could have downloaded from Apple iTunes for £9.99 – which is a little less, or a little more, than the CD price depending whether you compare with what I paid or the best current deal.

What is annoying though is that the iTunes download has two additional tracks:

  • 5.15 the Angels Have Gone
  • Days

They are probably nothing special; but it is irritating.

On the other hand, iTunes has its annoyances too. The tracks are lossy-compressed; and even if you don’t think the difference is audible, that is still a disadvantage if you want to convert to some other format, as generational loss creeps in. I miss out on the packaging (though there may be some digital booklet, I’m not sure). In addition, the rights I purchase are non-transferable, so if I decide I don’t like the album, I can’t stick it on eBay to reduce my loss.

The end result of each purchase is similar, as I rip the CD for streaming anyway.

On balance, I think the CD is a better buy; but I can see where this is going.

A few jottings on hi-fi and misleading science

My interest in hi-fi began a few decades ago  when I was out looking for a new cassette deck. At that time I had the view that all amplifiers sounded the same, pretty much, because I was aware that the frequency response of an amp was flat and its distortion low across the audible range.

I was in a store comparing a bank of cassette decks with a tape of my own that I’d brought along and a pair of headphones. There were a couple of amplifiers and two switchbox comparators, so I could listen to several decks through one amplifier, then several other decks through the second amp.

I began to suspect that the comparison was unfair, because all the decks going through the first amp sounded better – more musical and enjoyable – than those going through the second amp. I realised that contrary to my expectation the amplifiers were contributing to the sound, and that the first one sounded better. It was a Cambridge A&R A60. So I bought that instead, and loved it.

I realised therefore that the frequency response and distortion specs were not telling the whole story. It was better to buy what sounded best.

Unfortunately subjectivism has problems too. In particular, once people have been trained to distrust specs they become vulnerable to exploitation. Listening alone is not enough, for all sorts of reasons: what we hear is influenced by expectations, small variations in volume that we mis-interpret as quality differences, changes in multiple variables that make it impossible to know what we are really comparing, and so on. We need science to keep the industry honest.

Another factor is that advances in technology have made it harder for the hi-fi industry. Digital music eliminates things like wow and flutter, rumble and surface noise, and audio quality that is good enough for most people is now available for pennies. In search of margin, hi-fi retailers settled on selling expensive cables or equipment supports with ever-diminishing scientific rationale. Beautiful, chunky, elegant, gold-plated interconnects look like they should sound better, so like jackdaws attracted by shiny buttons we may think they do, even when common sense tells us that the audio signal has already passed though many very ordinary cables before it reaches us, so why should the particular stretch covered by this interconnect make any difference?

My respect for the power of the mind in this regard was increased by an incident during the Peter Belt years. Peter Belt was an audio eccentric who marketed a number of bizarre theories and products in the UK, mainly in the eighties, and attracted some support from the hi-fi press. See here for an enthusiast view of his work; and here for a woman convinced that she can improve the sound of her CDs by putting them in the deep freezer for 24 hours:

Freezing The Downward Spiral made it far more engaging than it has ever been. For instance, the layers at the end of the song "Closer" are more in evidence. Little bits of sound present themselves that I have never heard before. NIN’s sound is close to industrial, with what at times sounds like machinery droning in the background. After freezing this disc, these sounds became more easily discernible. The overall NIN experience increased tenfold for me after freezing the disc.

Another of Belt’s theories is or was that you could improve the sound of any hi-fi equipment with four supports (such as small rubber feet) by placing a triangular sheet of paper under one of them, to make it in some mystical sense three-legged.

I tried this with a friend. He had a high-end turntable and knew nothing of Peter Belt or his theories. I told him I knew of a madcap theory that I wanted to disprove. We played a record, and then I said I would make a change that would make no difference to the sound. I took a small thin triangular piece of paper and placed it under one of the four feet of the turntable. It did not affect its stability. We played the record again. He said it definitely sounded better. What is more, I thought it sounded better too – or at least, that was my subjective impression. My rational mind told me it sounded just the same. Still, he left the bit of paper there.

I don’t doubt that we have more to learn about sound reproduction; that we measure what we can, but we may measure the wrong things or in the wrong way. That does not mean that every wild theory about how to improve hi-fi has equal validity. There is one simple technique that helps to assess whether some particular thing is worth spending money on, and that is blind testing. Listen to A, then to B, and see if you can tell which is which. If the differences you hear when you know which is which disappear, then you know that the feature you are testing does not affect the audible sound quality. It might still be worth having; there is no law against liking beautiful cables or shiny amplifiers that cost more than a house.

I suspect that few or none of Peter Belt’s improvements would survive such trials.

Blind testing is not perfect. Even if you can hear a difference, that does not tell you which sounds more accurate to the source, or which is more enjoyable. Ironically, very poor equipment has nothing to fear from blind testing, in that it will most likely sound different; though there is merit in scoring your preferences blind as well.

Sometimes blind testing yields surprising results, like the trials which show that high-resolution audio like SACD and DVDA can pass through a conversion to CD quality and back and still sound the same. I’ve written more on this subject here.

I think we should learn from such tests and not fear them. They help us to focus on the things that yield less contentious improvements, like using the best available sources, and maintaining excellence all the way through from initial recording to final mastering. In the strange world of hi-fidelity neither specs, nor price, nor casual listening, nor even science will tell us everything about how to get the best sound; but some combination of all of these will enable us to spend our money and time wisely, and do more of what really counts: enjoying the music.

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