Compression Depression


“Research finds MP3s make your music sound more depressing” says the latest bit of breathless reportage to come floating down the audio/science news feeds. In this new ‘post fact’ age, I guess I’m no longer supposed to be surprised by the paucity of actual evidence offered up in support of any particular assertion put forward as scientific ‘research’ but in the interests of actual reality, let’s focus the Hummadruz lens on this affair.

As usual, nearly every mention of this that I saw completely uncritically regurgitated copy that looked like it came from one source. I couldn’t narrow it down to a first instance, but the coverage from NME was typical:

New research has found that listening to music in low-quality digital formats can dampened its emotional impact.

According to a study by the Audio Engineering Library, MP3s can have a distinct effect on the “timbral and emotional characteristics” of the instruments involved.

Researchers compared responses to compressed and uncompressed music over ten emotional categories at several bit rates.

It’s always instructive to find out who is responsible for research, so my obvious first action when I read the above quote was to click on that link to the ‘Audio Engineering Library’ and find out who those dudes actually are. Puzzlingly, the link just leads to the abstract of the actual paper, which makes no mention of that organisation.

In fact, searching the web for the ‘Audio Engineering Library’ reveals that there is no such entity, and, instructively, pretty much every search result leads to some variation or other of the story about ‘How compression makes your music depressing’. It’s a veritable self-referential maelstrom. Audio Engineering Library? Someone just made that shit up.*

If ever there was an indication that we are about to enter the land of hogwash and horsepiss, here we have it.

Still, we have the paper right? Published on Researchgate – the science industry equivalent of LinkedIn – to be sure, but proper science will out!

The first thing we should note is that this research is a one-off  publication, on an online site, of a conference presentation. The research it entails has neither been replicated, nor peer-reviewed. This is, in scientific terms, not much more than a bunch of opinions.

We don’t have to delve far into the paper to find its true worth:

3.2 ListeningTest

We used eight sustained instrument sounds: bassoon (bs), clarinet (cl), flute (fl), horn (hn), oboe (ob), saxophone (sx), trumpet (tp), and violin (vn).

Whoa there cowboy! I was told by NME that the compression made my music more depressing. You do know what music is, don’t you NME? What it is not, is a bunch of fixed-note sustained instrument noises taken entirely out of musical context.

In addition to that complete clanger, there is no mention anywhere in the paper about how many subjects were used in these tests, nor anything about how they were conducted – just a lot of technical hocus-pocus about compression methods, and some graphs that are totally meaningless given what we just read. Wading further through this procedural mess, we find so much experimenter subjectivity stirred into the mix that the study is rendered all but useless as a piece of viable science.

To sum up, an unpublished, un peer-reviewed paper, conducted by a fictional institution,  tells us that in an un-replicated study, an unspecified number of listeners (keeping in mind that could be as few as two) were played compressed timbral instrumental single tones (not music) and asked to subjectively choose – from a list pre-determined by the researchers – how those noises made them feel.

Would you conclude that from there you could get to “Research finds MP3s make your music sound more depressing”?

No, me neither.

*Addendum: It seems they probably mean the AES (Audio Engineering Society) Library, where the paper is also archived. So let’s chalk that one up to sloppy journalism, rather than wilful deception. On the AES site, the presentation appears under its actual title The Effects of MP3 Compression on Perceived Emotional Characteristics in Musical Instruments [my emphasis].

Notice that this doesn’t make any claims about music, per se, and is a much more accurate appraisal of what the study was actually looking at (see comments below for further clarification).

It’s Just Not Crickets

I’ve noticed that a rather old piece of ‘science’ trivia is floating around the social feeds again, and I thought this might be a good Hummadruz opportunity to dispel the myths surrounding it once and for all.

The story is this (as reported breathlessly on many incredulous sites but in this case we’ll be using text from

Composer Jim Wilson has recorded the sound of crickets and then slowed down the recording, revealing something so amazing. The crickets sound like they are singing the most angelic chorus in perfect harmony. Though it sounds like human voices, everything you hear in the recording is the crickets themselves.

Here’s a version of the the recording on Soundcloud:

What you’re hearing is the supposed slowed down crickets, with the original speed crickets layered over the top. It certainly does sound eerie and somewhat choral. Amazing huh? The reportage of this phenomenon is frequently accompanied by this endorsement by Tom Waits:

Tom Waits (on Jim Wilson): “Wilson, he’s always playing with time. I heard a recording recently of crickets slowed way down. It sounds like a choir, it sounds like angel music. Something sparkling, celestial with full harmony and bass parts – you wouldn’t believe it. It’s like a sweeping chorus of heaven, and it’s just slowed down, they didn’t manipulate the tape at all. So I think when Wilson slows people down, it gives you a chance to watch them moving through space. And there’s something to be said for slowing down the world.”

The hyperbole that goes with the piece almost invariably makes much of the claim that the slowed down crickets are not altered in any way apart from the direct change in pitch, but is such a claim believable?

As a professional sound designer and composer of nearly 40 years experience, I’ve had a quite a bit to do with the sounds of crickets in my time. I’ve composed several works comprised of manipulated insect and bird sounds, and I’ve spent many long hours on numerous projects building unusual atmospherics from crickets and frogs. I know cricket sounds better than most people on the planet.

And the sounds in that clip from Jim Wilson don’t sound like merely slowed-down crickets to me. But hey, you don’t have to take my word for it. Let’s do some science!

Since the clip includes the sounds of crickets running at normal speed layered over the top of the slow ones, then it follows that we could just slow the whole thing down again and get the same effect, right? The low crickets would drop right down out of audible range, but the normal speed crickets would themselves become the magical choir sounds. So let’s try it:

Hmm. Just a single low tone. No three part harmonies there, nor any beautiful modal intervals like in the Jim Wilson version. To me this is not so surprising, because I’ve used this technique a thousand times – slowing crickets down inevitably delivers you a single tonal version of the original. Sometimes you might get rhythmic pulsing, or grinding noises, but that’s about it, and it’s always at one constant pitch.

If you know anything about how crickets make their sounds, none of this will be  surprising to you either. Like most insects that generate some kind of chirruping or rasping or droning sound, crickets use a mechanism called stridulation to create their loud noise. This is one of the most basic ways that a sound can be generated: friction of one body part rubbing on another creates vibration. It’s essentially a variation on the effect you get by running your fingernails up and down a washboard.

Insects can achieve stridulation in a variety of ways, but in nearly all cases, they will, through limits of their anatomy, achieve just one basic pitch, or ‘note’ – just as we’ve seen in the slowed-down example above. For them to be yielding complex melodic structures like those in the Jim Wilson track, requires an explanation that I’m sure you will find as irksome as I do: that different crickets are making different pitches and that they’re then co-operating to create choral masterworks in human melodic modes. Specifically in Western liturgical scales, at that. If that’s what’s going on here, then there are at least a half dozen major scientific discoveries waiting for an enterprising biologist to claim.

The truth is well to the contrary. When you hear insects making noise, they’re far from being co-operative. They have no interest at all in harmonising with their pals to sing the glory of God. They are in fact competing with one another. Aggressively. For sex. The loudest and most impressive gets the prize. That is all.

So, how do we explain, then, the eerie vocal harmonising in the Jim Wilson recordings? In my opinion, as a composer and performer who is very accomplished in these techniques, the answer is completely obvious. The simple, single note tonal drones of crickets lend themselves perfectly to being raw material for a popular modern instrument: the sampler. With a music sampler, a sound can be tuned across the musical scale in such a way that it can be played on any note desired. I believe that Jim Wilson has taken the monotonal cricket sounds as his basic building blocks and then played whatever melodies and harmonies he wanted with them.

There’s nothing wrong with doing any of that, of course – there have been some wonderful musical explorations of this idea – but to promote it as some unexplained natural phenomenon with supernatural overtones is at least irrational, or at worst, exploitative.* And disappointingly human-centric.

The unadorned sounds of the natural world are beautiful in their own right and there is really no need to invoke human notions of value for them to be emotionally powerful. Learn to listen to those sounds for what they are. Here is a good starting point: the wonderful natural recordings of my good friend Andrew Skeoch through Listening Earth.

*Jim Wilson sells these recordings under the title ‘God’s Chorus of Crickets’. It is important to note that he himself does not anywhere make the claim that the recordings are just slowed down. To the contrary, these are his own words: “I discovered that when I slowed down this recording to various levels, this simple familiar sound began to morph into something very mystic and complex...”  The ‘various levels’ he’s talking about are chromatically tuned intervals. But he’s certainly not – as far as I’ve seen in my broad investigations – actively contradicting the numerous sites that claim the sounds have not been manipulated.



In recent times a number of devices have appeared on the market that promise to deliver a better musical experience than the one you usually receive from your portable digital music player of choice. One such gadget was brought to my attention yesterday – it goes by the name of the Chord Mojo.

“Simply connect Mojo to your iPhone, Android phone, PC, or Mac,” says the site, then “plug in your headphones and you can experience crystal clear audio the way you would hear it in the recording studio.”

So what’s the deal? Can this £300 (US$430) box really deliver on that promise?

Well, maybe. Like so many things in the shadowy world of audio snake oil, the claim comes with some caveats which the manufacturers assiduously avoid bringing to a potential customer’s attention.

The Mojo is what is called in the business a DAC, or Digital to Analog Converter. As you are most likely aware, the music on your portable music device is stored as digital bits. Those bits need to be converted into analog sound waves for them to be heard by your ears. Your musicpod obviously already does this – otherwise you wouldn’t be able to hear anything – but gadgets like the Chord Mojo claim to be able to do it better. To achieve this marvellous feat, the digital-to-analog converter and headphone amplifier circuit on the musicpod is bypassed altogether, and the (bulkier than an iPhone) Mojo plugs into the USB or Lightning socket on your device. You then plug your headphones into the  Mojo, which does the heavy lifting of converting digital bits into analog audio and then amplifying it (in a presumably more-sophisticated way than the DAC in your iPod).

But does it do what is claimed on the box? Probably, in a technical sense, yes. The real deception with products like this is elsewhere, so we have do a little sifting to find where the truth actually lies. Take that sentence from the website: “…crystal clear audio the way you would hear it in the recording studio.” That’s an amazing pledge – is that really what you could expect if you just plugged it into your iDevice straight off the shelf?

I doubt it. The truth is that this promise is based on something that the makers of the Mojo neglect to mention: it all depends on how your music files are made. If, like the great majority of people, your files are compressed into mp3 or AAC file formats, it’s simply a lie. No DAC, no matter how good, is going to make your mp3s sound like ‘audio the way you would hear it in a recording studio’. It’s even a highly contentious claim, in fact, to say that it would necessarily make your compressed music sound any better than the DAC already present in your music player does.

Now, if you happen to carry all your music around uncompressed (and I know absolutely no-one who does that – not me, nor any of my very experienced audio professional friends), you might benefit from a better DAC than the one in your iPod. Might. Because this would also depend on other factors, one of those being that a pair of Sony ear buds (like the ones in the promotional photo on the Chord Mojo site) would not aid you in this pursuit. In other words, a great deal depends on the quality of the headphones you’re using; tiny ear buds, no matter how good, will not deliver you ‘audio the way you would hear it in a recording studio’.

What the Chord Mojo site – and indeed, most other sites selling these portable DACs – leads an unknowledgeable reader to assume is that buying this expensive gadget and simply inserting it in their normal setup will give them better sound.

It won’t.

Hummadruz advice: If you really care about your music sounding better, just listen to it off CDs, or make uncompressed digital versions. And, if you do happen to have a cool $400+ burning a hole in your pocket, invest in a decent set of headphones.



“Science Confirms That Freddie Mercury Was Basically The Most Amazing Singer Of All Time” screams one headline. “Freddie Mercury Is The Greatest Singer Of All Time, Because Science Said So” says another. “Queen’s Freddie Mercury Had One Of The Best Singing Voices Of All Time, According To Science” gushes a third. I’m sure you saw them in your social media feed in the last week or so.

So what’s the story then? Have scientists come up with some amazing new method for applying empirical assessment to artistic subjectivity? Has scientific endeavour somehow managed to ‘confirm’ that Freddie Mercury is indisputably the most accomplished singer in human history?

Well, as you might have guessed, not so much.

Let me say from the outset that, by a considerable agreement of subjective reckonings, Mercury is an amazing singer. His vocal prowess is all the more extraordinary in light of his lack of formal training; he was self taught instrumentally and vocally, and claimed not to be able to read music. We really don’t need science to be able to legitimise his talent, per se.

And indeed science is not even attempting to do any such thing. The hyperbole above is generated by the lamest corners of the social media press, after the recent publishing of a paper by Christian T. Herbst et al, from the Faculty of Science at Palacký University, Olomouc, in the Czech Republic. Herbst frames the intentions of the research like this:

“The purpose of this study was to conduct a viable analysis of publicly available data material, in order to arrive at more empirically based insights into Freddie Mercury’s voice production and singing style.”

So the researchers, who self-describe their work as ‘fan science’, take it as a given that Freddie is an awesome singer and are simply gathering some data to help understand – in a technical way – how he did his stuff.

To do so, they examined both his speaking and his singing voice, concentrating on its timbral qualities, vocal range, vibrato and vocal subharmonics. In addition, they had a trained singer emulate some of Mercury’s vocal stylings and observed the active vocal cords with an endoscope. It is all fairly fascinating in its own right, and the breathless exaggeration from some sections of the interwebs really does the science no favours.

So what do the results of their efforts tell us? Well, not a lot that an experienced singing teacher couldn’t have concluded just by listening, in all honesty. They found that Freddie’s vocal style encompasses a remarkable variety of techniques, including a faster than average vibrato, the occasional use of vocal subharmonics (mostly to add a growl or burr to his voice) a proficient control of phonation and an impressive vocal range (although not quite the four octaves often claimed).

The paper provides empirical details of all these things, although, surprisingly in my opinion,  not much investigation into Mercury’s falsetto, which was one of his most dramatic vocal accomplishments (Mercury showed an almost incomparable ability to elide from his upper vocal register into falsetto and back again with virtually no audible transition – singers will tell you that this is very difficult to do).*

So to sum up, we already knew that Freddie Mercury was a pretty astonishing singer. What this investigation does is shed a little bit of scientific light on how he did his thing. What it does not do is ‘prove’ anything about his standing in the dominion of wonderful singers through the ages. And truly, that task is simply not the concern of science.

You can read the full technical paper ‘Freddie Mercury—acoustic analysis of speaking fundamental frequency, vibrato, and subharmonics’ here.


*You can hear many examples of this in the early Queen albums Queen, Queen II and Sheer Heart Attack. It is notable on the songs Lily of the Valley, Nevermore and The March of the Black Queen. Mercury’s use of the technique diminished as the band became more conventionally ‘rock’ oriented in later years.