What defines sound?


So, what is sound?

Most definitions will teach you that sound is vibration of the air around us. Let’s expand on that and introduce the idea that sound is what our ears detect and our brains decipher as such. The fact that our ears are playing the role of microphones that capture vibration of the air is just half of the story. Our brain does most of the work. People with hearing implants have a chip that stimulates hearing center in the brain. After receiving an implant they go thru process of adjustment to the new sense. For them air vibration part is not relevant anymore, their brain is “listening” to implanted electrodes. They receive electronic signal obtained from external microphone and sent thru the transmitter to the implant. Instead of the air vibrations around them they could be receiving signal from local radio station if they wish.

If one day space aliens land on Earth, they might not be able to hear us at all even if they have hearing mechanism similar to ours. Their hearing might be at different frequency range or their brains might have different circuitry for processing the sound.

Also, there is psychological perspective to the whole thing.  We have been listening to this planet’s sounds for millenias and we perceive them in a certain way. Our brain learned to discard some sounds as not important There are good reasons we don’t hear as bats or many other animals do. The way we hear has been fine-tuned to serve many useful purposes to us humans on this particular planet. If conditions were just a bit different, most likely specs for our hearing mechanism would be different as well. Even among humans, hearing abilities differ slightly. Size of our body, head, ears, genetic predispositions, it all causes small variations in how we perceive sounds but everyone can learn to become a good listener.

And what about music?

Music is something we’ve learned to process over time as well. We have adapted our tastes, developed instruments and various rules for playing them. I bet most of us wouldn’t be so pleased with music variety if we get sent thousand years into the past. Sound of most instruments was not as polished as it is today or they were not yet invented. It took centuries to refine them, and that process is ongoing.

As sound generating tools evolve and artist find new ways to play them, our music tastes change.

We need to be open minded about the sound and music. As you’ve probably already discovered, some things sound good to our ears because we have developed certain taste for that type of audio information but that changes over time.

Published on Audiowave February 23. 2014.
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Even two channels is sometimes one too many


Movie sound effects thrive in multichannel environment. They are short and fast and add to film’s atmosphere by feeding additional spatial info to our brains. More action on the screen, more channels we want to have to pinpoint where that sound is coming from.

And what about the speech and music? Well for speech is easy. One channel, right in front of us is all we need. Voices from any other directions do not play well with our  sanity.

Music is the tricky one. If our preferred method of listening is one instrument at a time then mono would be the answer. Imagine sound of a cello. Actually imagine a cellist sitting right in front of you and playing. Now put that cellist in a loudspeaker box. Still one cellist, right? Place that box right in front of you and listen. You will hear beautiful reproduction of a cello recording. Sound radiates straight toward your head, goes around you, bounces of the walls, some of that sound mixes with the original just to make you aware of the space you are in and that’s it. It is single point source of sound and there is no reason to break it into multiple channels.

Let’s add another musician. For example a clarinet, which plays with our cello. We need to supply information to the listener whether clarinet is placed right or left from the cello and we use stereo configuration. Now let’s add pianist that plays with other two. For this we need third loudspeaker? Of course not. Stereo is still all we need even if we add whole orchestra to the picture. Our brains will use spatial cues and tell us where musicians stand.

Why then multichannel setup for music listening? Mostly to sell you more speakers. Unless you are fortunate enough to always listen to live music  sitting surrounded by a circle of professional musicians! When we go to enjoy live music, musicians are on the stage in front and all that information is contained in stereo image. There are no musicians behind you and you don’t want reflections of the venue walls on your side channels. You want sound to arrive from stereo source in front of you and bounce off the walls of your room. Anything else will just make you dizzy because microprocessor in your head will overheat trying to adjust to all those fake spatial cues.

If we are able to see the sound in the room, one more thing would come into play. Each time we add another sound source to the room it tends to mess with the rest of them. When we are listening to single point source all is good. Sound energy nicely propagates thru the room, bounces off of few objects and walls, gets reflected or absorbed along the way, but it rarely causes much trouble unless all surfaces are really reflective. Now add another speaker. Our poor cellist gets divided into two half-cellists and then our brain is asked to reassemble it while these two half-cellists are canceling each other at different parts of the room and at different frequencies.

If we break poor cellist into more pieces and scatter the sound throughout the room using multiple boxes, all kinds of cancelations and reflections will occur.  Music waves from different sources tend to add and subtract with each other depending on the phase difference caused by a distance.  Where they subtract sound is missing, where they add sound is unnaturally loud. Our brains tend to compensate for that by filling the blanks, but it is much easier and more enjoyable to keep things simple. Multichannel music was futile attempt to jumpstart music industry, and sell more software and hardware. When you have chance go listen to live unamplified performances. When not, nice stereo system will play your carefully chosen music just fine.

Published on Audiowave February 23. 2015.
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Great grandpa’s tape deck


In 1973 Sony published the ad for open reel deck TC-377.
It read: “This could be the tape deck you’ll leave your great -grandson.” It went on explaining that heads will last 200 times longer and how machine had all kinds of additional features including ability to mix sources.

It also looked quite heavy. Great-grandson will probably have hard time lifting this thing. If designers tried reducing the size instead of adding knobs to it, machine would rate better in the unknown future.

And why not great-granddaughter? Because back in 70s Hi-Fi belonged to men and was mainly displayed in their man-caves. Nobody could predict that the same company will within a decade sell millions of Walkmans to girls on roller skates.

Where people at Sony really thinking that the deck will be used in 50 or more years? Marketing people who designed the ad didn’t. They were just thinking how to sell it during holidays season.  But engineers probably did.

As wise coworker once told me, “engineer is worth as much as his or hers last project”.  They poured their heart and soul into this product. At the time this was the most advanced way to record and then play sound at home. It was difficult to predict that digital revolution is around the corner. They took all parameters of the tape, its magnetic hysteresis and everything else into calculation and concluded that for consumer market this is the dream machine.

Things couldn’t be built much better neither by them nor their competitors. They engineered it to perfection and they were proud of themselves. Next 50 years belonged to them. After all, turntable/phonograph already ruled for almost 100 and it was time for a machine with recording capability to rightfully take the throne. It was perfected since 30s and it was in its prime. King was born and unfortunately forgotten in very short time.

Still, we need to thank all the engineers who worked so diligently on this and similar products. Their desire to create the product is not based on marketing decisions. They really want to give world the best machine for sound re/production that given budget allows. Just sometimes timing is bit more fortunate than in this case. Looking from today’s technological perspective, it would be a surprise if lucky grandson or granddaughter one day have any clue what machine is for.

Nevertheless, I would be so happy if I get to inherit one of these. Hypnotic glow od VU-meters and warmth of tape distortion. Maybe even few tapes recorded back then witnessing of past times. Instead, I kept my Sony WM-DC6 for future generations. Hopefully they will appreciate to hear the story about the times of magnetic recordings and be interested in listening to few cassette tapes  that I had saved in old shoebox for them.

Published on Audiowave February 22. 2015.
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Modular audio system in your pocket

Project Ara – aluminum case and modules.

With the announcement of Motorola’s project Ara, there might be an excellent opportunity to get ultimately configurable mobile audio device.

Ara is open platform for mobile with multitude of available slots which can be filled with any hardware you can imagine. So, let’s configure device for an audiophile. Of course we would start with a touch screen to be able to control our mobile audio system. Then, let’s add some nice, low noise processing module that will drive the rest of the system.

Next, insert large card with best available D/A converters, volume control keys, 3.5mm jack receptor and small amp capable of driving headphones for listening on the go.

On the end add a battery and fill all remaining slots with storage.

That would make basic hardware. OS will be variant of Google’s android with hardware drivers written by module developers.

Ara’s aluminum frame has magnetic slots of different sizes. There is decent amount of space and some of the cards can be fairly large to fit quality components.

Remember days of making home entertainment system using PC hardware? Here we just do it on a smaller scale and pack into much better looking package. Each card can be custom designed to  match the look of device or have manufacturer’s branding.

Variety of other functions come to mind. One card could have FM or HD tuner. Wireless card can be installed to stream audio. If you are card maker, you can go wild with your imagination and make tape deck card if you really want. Ok, that’s less realistic, but there could be HDMI card to drive TV and play surround sound.

A/D card could turn it into high quality recorder and two microphone cards could house large enough membranes to record your favorite band in the concert. If you want video of that concert, just insert another card with a camera.

And if you have too many cards, chances are that you don’t need them all the time. Microphone cards should stay safe at home when you don’t plan to make recordings

Apps that play, manage or record music can be written by manufacturers of the hardware or a totally different software developer.

Your favorite music player app should be able to talk to your D/A card and play FLAC files from the storage card. You might decide to get card with digital output and use external DAC when at home.

And on the end you can even add phone card just so you don’t look like total audio nerd. Wireless cards can introduce noise – you might have to remove or disable them when seriously listening to music.

Google is about to open this platform for developers and there is good chance that large and small audio equipment makers will see the opportunity in developing modules for Ara platform.
So no matter what audio components your ideal mobile audio device should have, there might be a card for that in not so distant future.

Published on Audiowave April 6. 2014.
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First thoughts on Pono Audio Player

Pono Hi-Def audio player
Pono Hi-Def mobile audio player

Everyone seems to be talking about Pono player these days, and not just audiophiles. Most people interested in Pono used to be into audio gear or music when they were younger and still occasionally enjoy listening to well produced albums. They are suddenly awakening from a long hibernation and remember that they were once passionate about the subject but gave up when HiFi equipment became plastic and music became over-processed and over-compressed. Riding on this new wave of enthusiasm let’s try to analyze what is the possible future of Pono audio platform and generally high definition (Hi-Def) listening in the foreseeable future.

What is Pono?

Pono is name of portable digital music player using quality electronics circuitry and capable of decoding Hi-Def audio files in non-proprietary Free Lossless Audio Codec (FLAC) format. PonoMusic is an ecosystem built around the player to sell FLAC files encoded at high resolutions for download.

Pono’s promise

Biggest Pono’s promise is not just in making a cool new player, it is more about challenging the way music is produced. This is nowhere mentioned but it is what many are hoping for. That recording revolution is why people are excited about this project – they actually want to go back to the basics. Pono suddenly awakened the audiophile spirit in many people who nostalgically remember times of solidly built stereos that illuminated rooms with LEDs or VU meters in their student days. Music was simpler at those times and albums were made with real musicians. There were no Auto-Tune and endless amount of overprocessed tracks layered on top of each other during production. Studio’s recording decks had limited amount of tracks and once you were done with drums, basic instruments and vocals, there was not much space left for additional stuff. It meant that you could actually hear every instrument in the mix. In the world of recording engineering less is more. Of course there are artists who still follow that golden principle but many became lost in abundance of tracks and effects that computer based recording had brought. It is not a surprise that people are dusting-off turntables and spinning old records instead of buying new music. Releasing existing albums in high resolution is improvement but producing new ones with advantages of Hi-Def audio in mind is what is really needed. If used wisely, greater dynamic range will give more breathing space for all the sounds to fit into the mix. Pono will raise the bar and new recordings will have to follow.

Is mp3 really that bad?

Pono marketing is cleverly presenting mp3 as an evil empire. Besides being lossy and proprietary format, mp3 isn’t actually that horrible and it is the lesser of two compression evils. Just try it for yourself – get a really well produced album and convert it into mp3. Play it on any decent system and most of the people will be fine with what they hear. Now, play something really new and popular from the radio on the same system. Hear it? This is where most of those bad guys are hiding. Hint: At the end it all comes down to dynamic range. Music compressed into mp3 masks some detail but original dynamic is still mostly there. Of course, lossless format is way better but before blaming everything on data format and resolution let’s try to figure out what is the more important reason why recent recordings have lost their soul.

Dynamic compression vs. data compression

It is important to differentiate between two types of compression we are dealing with here. First is being blamed for everything and second is not mentioned at all. Data compression is a computer term. Various algorithms are employed to make audio file use less storage space in computer memory. One of them is mp3 format and your mp3 player is actually a small computer that manages these files. Algorithm works by mostly using psychoacoustic tricks to remove sounds that otherwise mask each other and therefore are inaudible to most listeners. You probably felt uneasy when you learned about these computerized surgical methods making listening decisions for us but this allowed for huge savings in storage space and in download time when storage was expensive and download was at dial-up speed. Nowadays there is less reason to compress music files – except in case of mobile phones. Dynamic compression can be done for many purposes and the most common one is to make audible the quietest parts of the song. This is done by taking music information from the entire dynamic range and moving it above noise threshold. Imagine that you have bus full of people and you need to move them to an even smaller bus. Data compression would first remove all the passengers that look similar to each other while dynamic compression would squeeze them all into the smaller bus even if they are not comfortable in there. These two types of compression are done for two entirely different reasons and have nothing in common except the fact that both reduce the amount of sonic richness from the song. Data compression takes away the detail while dynamic range compression applied to the entire song squeezes the life out of music.

King of the radio

Common denominator for the music released in last couple of decades is abundance of dynamic compression. Each new hit had to be more loud when played on the radio. Good engineers are well aware of pitfalls of setting that compression ratio too high, still there is no shortage of compressor happy sound people partially because it is often requirement to get up to par with other hits on the charts. Music labels and bands enjoy benefits of compression since it is almost impossible to have hit on the radio unless it can compete with other songs in terms of perceived loudness. Also it gives that “punch” to drums and other instruments. In one studio session there can be variety of compressors applied to individual tracks. Then there is compressor on the end that compresses everything one more time. Mastering process might use little bit of compression as well. Once album gets finally out of that compressor madness into hands of broadcasting people they will compress it again before it gets to your radio. Some compression is good to control the levels and tighten the mix, but clearly we often end up with too much good stuff.

Hitting the road

If you are listening in the car, your car stereo might have a built-in compressor, as well. Although it is rarely documented, almost every CD player in cars has some form of dynamic control. Compressed music cuts through the road noise when driving on the freeway. Unless you are listening in a luxury car with extremely quiet interior, you will need some compression. That part when Mr. Young is taking people for a spin in his car to listen to Hi-Def music is a bit unclear to me. I’ve once listened to the music from my own portable CD player during a 6-hour trip and really wished I had a compressor with me because I was forced to ride the volume all the time to be able to hear quiet parts and not go deaf during loud ones. When listening in a car, we encounter a similar issue we had with cassette tapes – lesser quality tapes with more noise were good only for disco hits. If you try listening to any piece of classical music from the “normal” tape, it quickly becomes obvious that quieter segments are buried in the tape’s hiss. Accordingly, signal-to-road-noise-ratio has to stay at healthy levels in order to hear music in the car. Pono’s full dynamics might work in Neil’s Cadillac at low speeds, but some quieter segments will become inaudible as he drives faster. Beautifully reproduced sound from this fine device will unfortunately be overpowered whenever it gets below road noise threshold. Still, Mr. Young knows what he is doing. Static or slow moving car is an ideal environment for private listening sessions where he can control every parameter of the presentation. Driving at high speeds and trying to hear music with the widest dynamic range known to mankind would be a totally different story. Without compression we cannot hear “quieter” details of the song in the noisy environment and that’s the fact that no device will overcome.

Business model

Pono’s business model is genius. Notice that Hi-Def music exists already and almost no one has discovered it. You can easily equip your computer with high quality DAC and get songs from websites that sell high resolution audio files. But Pono connected it to the same platform, lowered the entry barrier by making it simple, and made it mobile. It practically claims all Hi-Def music as their thing and I wouldn’t be surprised if people start using the Pono term to refer to all music encoded at higher rate than CD. Execution of the actual store will make or break this project. Download to device should be easy and without too many annoying rules and limitations. Ideally it should allow users with their own DAC setups, not only Pono owners to buy HI-Def music from the store. People should be able to rate title’s technical quality online and that can increase the quality of new albums faster than any other approach. After all, record labels are in this for business first and art second, so public voting system that drives up sales of good quality tracks will give them an excellent indication of what production techniques customers prefer. Mr. Young’s partner is a seasoned businessman who can make all of these things happen. Hopefully they will keep listening to their supporters since they are the ones who will best advertise their platform. Audiophiles are an unusual bunch, they trust their peers and will spend the last penny for the product that scores good reviews.

Use of celebrities

Mr. Young gets lots of famous people from the music industry to endorse his product and by doing so they are reminding you that their albums will be available on PonoMusic. Statements that they haven’t heard anything like that before might sound a bit superficial, but at least those are real musicians talking about experience with the product, not some actor hired by the marketing agency. Young has access to them and that’s cool, and at the same time a bit funny to hear people who can afford any stereo system on Earth, plus have daily access to state of the art studios be so ecstatic about the sound of Pono. They were obviously caught in a moment, not expecting such sound from a tiny device.

Are we going to have two versions of each album?

So what if artist realizes that Pono version could be much more if it is specially mixed for Hi-Def player? It can have a wider dynamic range, and be less processed because it doesn’t have to be mixed for the radio. If you go to any studio, you will see mixing engineers testing their work on really cheap speakers, in addition to studio monitors. Then, on the way home, they will listen in the car, all to assure that mix will perform reasonably well on any type of consumer device. That step can be completely avoided when working on the Hi-Def mix. When you dial it up to sound perfect on a high end player, just leave it there.

Should I invest into this new format?

Yes, although if you have heard Bohemian Rhapsody in surround version, then you might have some doubts about another new format. There was a time not so long ago when surround mixes were thought to be the next thing and some albums were completely reassembled to fit that scenario. Besides complicated set-up, the only problem was that actual recording didn’t sound like you are positioned in front of the band where you belong, rather like band members were performing in a circle around the listener. Some serious engineering effort went into creating these mixes and resulted in a brief existence of a parallel universe for adopters of multichannel format. It didn’t last. Fortunately Pono is definitelly moving in the right direction. Two separate sets of mixes (one regular and one for Pono) will have to exist for each participating recording to get the maximum out of it. If you are deciding on which format to buy in the future, it is a good idea to opt for a Hi-Def one, particularly if reviews are good. You will get much more sonic information for your money.

Will this effort be properly supported by the labels?

Publishers are watching this closely. It presents great opportunity for them to sell you the same album one more time. Now that the Hi-Def idea is out, they will go for it, not that they haven’t tried before. They tested several Hi-def formats and none of them really took off. This time someone else is doing the legwork for them and the Hi-Def grassroots movement is growing practically on its own. What an opportunity for a publisher with lots of quality recordings, and also to be a collector of these because this is actually the first time ever you will get the same quality that they’ve got in the studio.

Can they give really old albums new life on Pono?

Question is how many of the old master tapes do really exist anymore. Tapes are known for losing their bond with magnetic oxide which means that really old tapes literally get their magnetic material stripped off during the digitizing process – tape is often ruined and the only copy left is the digital one. So if an older master tape is already digitized, let’s say ten years ago, quality is whatever capability of analog to digital convertors was at that time because there is no original tape in existence anymore to digitize again. And in ten years from now, the digitizing process shall improve even further but we might not have some of the tapes anymore to digitize them again. Magnetic tape and deck also had much narrower dynamic range than digital systems. Digitizing old albums with the best quality equipment will bring original fidelity of the recording to the listener, but what wasn’t there at the first place won’t magically appear. So expect older records to have slightly more details and mostly unchanged dynamic range.


Pono will no doubt fit nicely on your desk or next to your Hi-Fi system. You will be able to glance at what is playing without actually lifting the device like you have to do with any other portable player. At the same time you will need some big pockets to carry it around because shape is quite odd to fit in your jeans’ pocket. But if you already carry that backpack to store headphones, than Pono can go in there too. There is no point in using Pono with tiny earphones – for them, a regular mp3 player with cheaper per-track cost is good enough. To really hear what Pono has to say, you will need headphones that cost as much as Pono itself. Do yourself a favor and shop for real audiophile cans, not the ones that are trendy.


Pono uses high quality components, no question about that. New signal processing methods are used to improve on shortcomings of similar solutions. Few test batches are built before design is finalized which shows lots of attention to detail and some smart leadership that follows modern product development and manufacturing practices. They are open about technologies utilized inside the player which resonates very nicely with audiophiles who usually care about the type of DAC or capacitors being used.

Educating the listener

All this carefully nurtured bits of audio information need good ears to hear it. And not only good, but also well trained. Some sonic details are so minute that only a versed listener will be able to spot them. Positioning instruments in space is another listening skill that for some people takes years to develop. And so on, it takes experience to become a sonic geek. Some people just won’t be able to notice a difference that easily in the beginning. What amazing times we live in, when such level of sound information is available in our pockets just 30 years after the Walkman era. But don’t expect that you can just slap Beats headphones on everyone’s head, plug them into Pono player and they will proclaim it the best sonic experience ever. Some people just won’t notice a large difference at first, however they will have the right tool to develop their listening skills.

Expectations are high

People already own iPods with thousands of songs and certain percentage of them want something sonically better. They already have a pretty great device and they are expecting even more.

Can Pono deliver?

It really depends on the quality and quantity or their music selection more than on hardware itself. I bet there are already ten other companies working on a Hi-Def player. Music library is another thing, it is quite an achievement to license existing tracks and repackage them in this purist format. It will be easier with future recordings but bands won’t go to the studio to remix old songs so any improvements can only be made in the re-mastering phase which can bring some improvements but not huge. After that, all that is left is to package these tracks with the highest possible bit and sampling rate. It will again be similar to when CDs were introduced, some recordings will sound amazing and others might just sound very similar like before. Only songs specifically mixed for this new delivery method will use its full potential. This little player might bring many good things to audiophiles and greatly influence the recording industry, so let’s give it as much attention as it deserves.

Published on Audiowave April 3. 2014.
If you use content from this article, you must credit audw.com