Fiio X5 Portable Hi-Res Music Player

Fiio’s latest contribution to the world of sound and music came in the form of the X5 portable music player. Following on from the recent release of their limited edition portable amplifier, the E12DIY, the X5 is another statement from Fiio that they want to play at the high end of sound quality, even if the pricing is still only at the mid level (and for that we are thankful!)

Overview

  • Size:  67.6 x 114 x 15.6 mm
  • Weight:  195 g
  • Storage:  2 x micro SD (TF) card slots – max capacity 256Gb at time of launch
  • Line-out:  1.5 Vrms
  • Output impedance:  <0.26 ohms
  • Recommended headphone impedance:  16 – 300 ohms
  • Max output current:  >150 mA
  • Max output voltage:  8 V (peak-to-peak)
  • Battery life:  > 10 hours
  • Sample rates:  up to 192 kHz / 24 bit

There are plenty more specs available on the Fiio website (fiio.com.cn), but to me these are the key elements that show the general versatility of the X5. There are some further outstanding numbers such as crosstalk and signal-to-noise ratio, but there are different figures for the amped headphone out and the unamped line-out so I’ll let you look these up yourself to as not to overload everyone with numbers.

The X5 retails for around $400 and offers the same compatibility as other much more expensive players. However the question is whether it offers the same performance? I bought the X5 to replace my far more expensive RWAK100 so outstanding performance was a must and I haven’t been disappointed… for the most part.

To read the rest of the review, please head over to the new Passion for Sound site. It’s sexier and there’s plenty of great new content coming soon, but only on the new site. Hope to see you there!

 

iRiver AK100

I’ve called this review “iRiver AK100”, but it probably should be called the iRiver Astell & Kern Red Wine Audio RWAK100. I’l explain…

iRiver AK100 boxThe AK100 is originally designed by Korean electronics company, iRiver, in collaboration with Astell & Kern who seem to have appeared as experts in the hi-resolution / mastering quality sound space. Their site, www.astellnkern.com doesn’t really explain where their expertise comes from, but there’s no doubting that their influence has been positive on the sound quality from the AK100.

So where does the Red Wine Audio reference come from and the “RW” part of the model number (RWAK100)?

For some unknown reason, the designers of the AK100 decided to create a player with a 22ohm output impedance. Don’t worry if you don’t know what that means; I’ll explain. Almost anyway you look at it, a device used to drive portable headphones and earphones needs to have an output impedance as close to zero as possible. Most of the best devices have output impedance <2 ohms so 22 is way out of the ball park. What it means is that the AK100 can sound completely different from one earphone to the next, particularly with high-end, multi-balanced armature earphones like custom IEMs (e.g. Unique Melody Miracles). As a portable player, there is no good reason to create a device that completely changes (not for the better) the sound of almost every earphone or portable headphone on the market.

So along came Red Wine Audio…

Red Wine Audio is an American company renowned for their audiophile devices and the all famous iMod modification to the Apple iPod. When Vinnie from RWA got a hold of the AK100, he identified a way to bypass the 22 ohm resistors and create an AK100 with <1 ohm output impedance. And so the RWAK100 was born.

There are other modifications available from different companies. All do the same thing essentially, but my experiences are with the RWA variant and my experiences with both the product and with Vinnie have been stellar!

For the rest of this review, I’ll refer to the AK100 unless specifically referring to the RWAK100. The only difference is the output impedance and this only effects the sound quality with low-impedance ‘phones.

Design & Size

iRiver AK100 unpackedThe AK100 is a quality product. From the moment you open the box you know you’re using a prestige device. The whole case is a combination of aluminium and glass and it feels very well-built. Little touches really show how special iRiver / A&K wanted the experience to be. For example, below the player in the box is a little booklet with a micro SD card containing a selection of hi-resolution (mastering quality sound) tracks. The booklet provides information about each of these tracks. It’s a lovely touch to help you enjoy the AK100 at its full potential straight out of the box.

Another nice touch is the screen protectors. When you first open the box, the AK100 has removable protectors on the front and back glass panels. When you peel these off, you find semi-permanent protectors already fitted to the glass surfaces to protect from scratching (the same as screen protectors on a mobile phone). It’s another really nice touch. iRiver also provides spare screen protectors, but you’ll only need them if the pre-fitted ones get really scratched.

In terms of size, the AK100 is deceptively small. I had no idea just how small it was until I had it in my hands. AK100 iPod Video & NanoHere are 2 pictures with an 80Gb iPod Video (5.5G) and iPod Nano to show you exactly how compact it is (apologies for the image quality).

As you can see, the AK100 is shorter than both players. It’s the same width as the iPod Video (same as current model iPod Classic) with the exception of the volume knob on the left which protrudes just a tiny amount. The AK100 is a little lighter than full size iPods, but heavier than small iPods like the Nano.

AK100 Ipod Video Nano sideThe second image shows the thickness of the 3 devices. Clearly the Nano is much thinner, but also has less capacity and nowhere near the sound quality of the AK100 (or larger iPods). Without measuring them, I think the Ak100 may be a hair thicker than the iPod Video which also means it’s about twice the thickness of the current iPod Classic.

Capacity & Storage

Micro USB socket, MicroSD ports, Red Wine Audio badge

Micro USB socket, Micro SD ports, Red Wine Audio badge

The AK100 contains built-in 32Gb flash memory for onboard music and system files, but also allows the addition of 2 micro SD cards via a slot on the base of the device. The official specifications say that the AK100 can support up to 32Gb micro SD cards, but larger cards do work if formatted to FAT32 (larger cards come pre-formatted using the exFAT system).

Memory cards are housed under the slider shown in the image to the left. They’re a little fiddly to get in and out, but it keeps the device clean and tidy with no protruding bumps (other than the volume knob) or open holes into the circuitry.

Interface & Usability

The user interface of the AK100 has taken some flack for not being as smooth and intuitive as Apple devices, but recent firmware updates (v1.33 and v2.01) have made strides in this area. The following information is based on the current firmware (v2.01)

Starting screenMost navigation is conducted via the touch screen which, although a little small, is responsive and simple. Navigation begins with the home screen seen to the right. It shows the current track with artwork and some simple thumbnails to access your library in a number of ways including MQS which takes you instantly to a listing of all hi-res tracks on the device (e.g. 96kHz / 24-bit and 192kHz / 24-bit recordings). There’s also a cog button in the top right corner to access device settings.

All-in-all the interface with the new firmware is simple and intuitive.

AK100 now playingWhen you’re playing a track, there are a few options for the display. You can have just the art showing or the art as a backdrop behind track information. This is changed just by touching the screen. You can also change how artwork is displayed with choices between fitting to the screen or filling the screen. My photos show my preferred setting of filling the screen.

Other options that are easily accessed from the “Now Playing” screen are:

  • 5-band equaliser
  • Gapless playback
  • Boost
  • Detailed track information
  • Shuffle or continuous play

AK100 hardware buttonsThere are hardware control buttons on the left side of the player (as you look at the screen) with buttons for skipping forwards and backwards as well as playing and pausing. Holding down the forward and back buttons acts triggers a seek function (i.e. fast-forward / rewind).

One final point about usability is the volume knob. It is designed to allow some movement. Some people don’t like this, but for me it feels fine and I like the implementation of the volume control overall. The knob has a notched feel as you turn it so you can clearly feel the increments. The increments are also very small so you can’t accidentally deafen yourself.

If you do want to raise or lower the volume quickly, you can use the touch screen for rapid, large changes. After turning the volume knob, a graphic appears on-screen which allows you to touch and drag an orange volume bar. It’s easy and responsive.

If you’re worried about bumping the volume knob in your pocket you can also select to lock the volume control when the screen is off so, to me, iRiver have covered volume control really nicely and in a unique way. It took a little while to get used to, but I really like the results.

Battery Life

Thank you to Head-Fi user, edmonem, for asking about battery life as I originally forgot to include this information!

The battery in the AK100 normally lasts in excess of 10 hours (and quite comfortably in excess). I’ve been a little conservative with this number because the battery life will vary based on your individual usage habits. Regular skipping of tracks, continuous high volume, keeping the screen on, etc. will all drain the battery faster. With normal listening at around 55-60% volume continuously nets me long 10+ hour playback times.

Just as some of the usage above will drain the battery, using an external amplifier can extend the battery life significantly by presenting a much easier load to the AK100. You may also find variation depending on the ratio of hi-res tracks to 44.1kHz /16-bit tracks (hi-res tracks use more battery).

Format Compatibility

The AK100 will play almost any file you can throw at it. Common supported formats include FLAC, WAV, MP3, WMA, OGG, APE, AIFF, ALAC, and AAC. Some users have been discussing the desire for DSD, but this is currently not supported. iRiver have mentioned the possibility of support in future firmware updates although it would convert the DSD for playback as opposed to direct playback without manipulation.

Connectivity

AK100 in / out portsThe AK100 can be connected directly to headphones via a 3.5mm jack (top of image), but this also doubles as an optical output. It also has an optical input to work as a DAC for other devices with optical out. There is talk that it will operate as a USB DAC in future (i.e. for use as an external soundcard / DAC with computers), but no timetable has been confirmed for this feature.

I’ve successfully used the AK100 with all outputs / inputs and they all work brilliantly. You can control the volume when using the headphone output (including when listening to the optical input), but the output is fixed level when using the optical out.

Sound Quality

Simply put, the AK100 is the best portable source I’ve heard so far and is actually up there with the best source units I’ve heard at all. It easily keeps pace with any of the dedicated sub-$1000 deskptop DAC / amp combinations I’ve heard and yet it’s in such a tiny package!

The sound from the AK100 is wonderfully smooth, but immensely detailed. Unfortunately, it’s output impedance issue (discussed earlier) means that its sound can vary dramatically when paired with the low impedance ‘phones. Using an amplifier completely negates this issue and can further enhance the quality of the sound (if it’s a good amp).

Because I wanted the freedom to use the AK100 with and without amping, I chose to get the Red Wine Audio mod. The sound signature and presentation hasn’t changed significantly, but it stays consistent no matter what I connect to it – low impedance IEMs right through to high impedance headphones.

The most impressive aspect to the AK100’s sound is its cohesive and organic presentation. There is amazing detail with plenty of separation between different sounds, but everything also still sounds like it fits together. I was recently able to test the AK100 alongside the HDP-R10 (Japanese version of iBasso DX100) and found that the HDP-R10 seemed to separate sounds more, but to the point that I actually found the whole presentation began to sound like a collection of parts, not a single organic whole. There’s no denying the resolution and clarity of the HDP-R10, but I personally preferred the natural presentation of the AK100.

Overall, the sound style of the AK100 is smooth and a touch warm, but not lacking in detail or clarity. It sounds great playing regular 16-bit / 44.1kHz tracks and then really sings with hi-res, 24-bit tracks at higher sampling rates. It’s one of those devices that can really help you rediscover your music and hear it in a whole new way.

The Drawbacks

There are a couple of things I haven’t mentioned yet, but think are important to note.

The AK100 currently doesn’t support playlists created by common media management software (namely “m3u” playlists) or CUE files which tell a player how to split a single FLAC file into its individual tracks. iRiver report that these features are highly requested and on the way, but at the time of writing they were not available.

Another minor gripe which occasionally becomes very frustrating is the scanning feature. Anytime you load new tracks onto the AK100 or insert a memory card, the AK100 needs to scan the files to create a database for navigation. This can take a long time, especially when you’ve just unplugged your AK100 from the computer and want to walk out the door ready to listen to music.

You can switch scanning to auto or manual so that it doesn’t delay your listening, but if you don’t scan, you can only access your music by browsing folders, not by artist, genre, track names, etc. Some people are fine with this, but I like to access via the database, not by file viewer.

iRiver keep reporting changes in the firmware to help speed up the process, but it still isn’t at a level that’s easily bearable. Hopefully they’ll find a fix in the future, but in the meantime I’ve learned to think ahead and allow scanning time before trying to use my AK100.

These drawbacks are minor concerns given the amazing sound quality and overall performance of the AK100. I wanted to share the full picture, but don’t be turned off. There’s no such thing as the perfect player (yet) that combines top quality sound with usability, playlist features, seamless interface, etc. In my opinion, the RWAK100 is as close as it gets so far and there’s the potential that all the drawbacks mentioned above will be recitified via firmware updates in the coming months.

Summary

iRiver AK100 unpackedIf you have around $600 to spend on a portable music player and you already have an amp, the AK100 is a great option! If you can spend a bit more, or don’t have an amp, I highly recommend the Red Wine Audio version, RWAK100.

Other players on the market offer different price points and features, but nothing quite matches the AK100’s combination of size, performance and price – it’s a brilliant player and has quickly become one of my most treasured audio devices!

Bose IE2

There’s a lot of bad press from the “high-end” audio community towards Bose and although I would agree that Bose isn’t my choice for home music listening, they make brilliant home theatre systems that are near impossible to beat from a “bang-for-buck” and simplicity perspective.Bose IE2 earphones in their original packaging

That got me thinking, are their earphones and headphones really that bad? I’ve read a lot of hot debate on Head-Fi about Bose ear/headphones and didn’t know what to trust. A friend of mine who works for Bose was kind enough to share his IE2 earphones with me to test out.

Despite my friend working at Bose, I can assure you that this is an unbiased review. There are no strings attached and my single purpose on this blog is to share my impressions of different products and how enjoyable (or otherwise) they make our music.

To read this review, please head over to the new Passion for Sound website. It’s sexier and there’s lots of great new content. Don’t worry, the link will take you straight to this article.

Get some great sounding music

If you’re a fan of great sound or you want to really test the capabilities of your ears or your gear, here are a couple of resources you might love like I do.

HD Tracks

The first one is HD Tracks (www.hdtracks.com), a site specialising in high quality audio recorded (or remastered) at high sample rates and bit depth. Albums from HD Tracks mostly cost around $18 (AUD) and are mostly available as FLAC files, but in some cases there is the choice of lower quality MP3 files. They have a range of new and old recordings including artists and albums like:

  • Norah Jones
  • The Dark Knight Rises Soundtrack
  • Fleetwood Mac
  • Rolling Stones
  • Aretha Franklin
  • Otis Redding
  • Ella Fitzgerald

They also have a huge range of classical and jazz albums that I’m yet to explore.

The albums on HD Tracks range from 44.1kHz/24-bit recordings through 96kHz/24-bit to 192kHz/24-bit recordings. All of these are significant improvements over the 44.1kHz/16-bit standard of CDs. If you’re unsure of what all those numbers mean, here’s a brief, hopefully simple explanation.

All CDs are 44.1kHz/16-bit audio. This means that the recording system takes a snapshot of the sound 44,100 times per second and that snapshot contains 16 “bits” of information which equates to 65,536 pieces of information (like pixels on a TV – the more pieces, the higher the resolution). The theory behind the 44.1kHz sampling rate of CD audio is that humans can only hear up to 20kHz and so CDs are capturing information more than twice as fast as the human ear can detect.

44.1kHz audio is mostly good enough. You will hear some improvement to the smoothness of the sound at 96kHz and possibly at 192kHz, but at 192kHz it’s debatable and may in fact detract from the music due to the processing power required for 192kHz sound. I choose to use 96kHz audio where possible, but am perfectly satisfied with good 44.1kHz recordings too.

Bit depth is a bit different. Just like a high definition TV looks clearer and sharper than a standard definition TV, the bit depth of audio is the same – more bit depth makes the music clearer and sharper. While there are just over 65,000 pieces of information recorded in each snapshot at 16-bit, 24-bit audio records more than 16.7 million pieces. That’s right, we jump from 65,000 pieces to over 16,000,000 pieces – a massive difference and therefore the sound is much clearer and sharper.

If you’d like to know more about sample rates and bit depth, there’s a great article here.

Grammy Awards – Engineering

Just today, I stumbled upon the interesting fact that every year, there is a Grammy award presented to the album with the best audio engineering. The list of past winners includes some albums worth listening to and a few that aren’t worth as much time (from a musical enjoyment point of view), but they are all beautifully recorded and will make your system shine and bring a smile to your face. There is a complete list of recent winners on the following Wikipedia page:

Grammy Award for Best Engineered Album, Non-Classical

As the name suggests, these are non-classical albums (pop, blues, rock, etc.), but there are also classical albums awarded and the list is also available on this Wiki page.

Having gone through my collection to listen to some of my albums on the non-classical list, I can confirm that they sound awesome and there are some great albums on the list by artists like Sting, John Mayer, Quincy Jones, and Ray Charles.

I hope you find some audio gems amongst the Grammy list or on HD Tracks. Happy listening!

 

 

 

Massive Portable Player Shootout

I’ve been using an iPod Video 80Gb (5.5 generation) for years now and have loved it, but my music collection continues to grow and I’m a fan of lossless audio (ALAC and FLAC) so it’s no longer large enough to hold all my tunes. I’m now at a major crossroads when it comes to finding the right combination of quality, capacity, and ease-of-use. There are a few options I’ve considered and I’ve been lucky enough to try all of them so I’m sharing the results here. I’d like to extend a massive thanks to Wing and the team at Minidisc.com.au for providing the Cowon J3 demo unit and outstanding customer service in my purchase of the Cowon X7 unit.

What’s Being Compared:

  • Apple iPod 80Gb (5.5 Generation) – middle of image
  • Apple iPod 160Gb (late 2009)  – top right of image
  • Cowon X7 160Gb – top left of image
  • Cowon J3 – bottom left of image
  • Sony 460 Series Walkman 4Gb – bottom right of image

If you’ve spotted the odd one out here (yes, the Walkman) and you’re wondering why I’m comparing a little 4Gb player to three hard-disk behemoths and a large-scale SD-based player, it’s purely thrown into the mix as a reference point to see how the expensive players compare to a relatively cheap option.

I’m comparing the players on 4 key factors:

  1. Sound quality (including power output)
  2. Size
  3. Interface & Ease of Use
  4. Customisation & Flexibility

Sound Quality

It’s very hard to conduct a subjective test of sound quality on audio sources because the only real way (short of complicated and expensive setups) is to keep switching your headphones or line-out cable from source to source. Because each of the player’s has a slightly different volume scale, it’s also hard to match the volume exactly and that can influence our perception of quality, too. I’ve done everything I can to minimise the impact of volume, delay between sources and personal preference. All players were tested with no sound “enhancements” (i.e. no BBE effects on Cowon products and no EQ or Sound Check on iPods). All testing was done using 320 kbps MP3 tracks to avoid any potential difference between ALAC and FLAC files. I used my Audio Technica AD900s, Ultrasone HFI-680s and HiFi Man Re0s with each player for a thorough sample.

The order of performance here is a little tricky, but essentially it’s:

First Place: Cowon X7 & J3 – Clean, rich sound with a massive open sound stage and all of the details perfectly presented. My only criticism of the Cowons is that they actually are a little under powered from a volume perspective. They have no trouble getting great sound quality out of the higher impedance HFI-680s and Re0s, but they are at more than 95% volume in order to create an energetic, exciting listening experience.

In addition to their naturally awesome sound quality, the Cowons offer the range of BBE features to further enhance your listening pleasure and although I normally steer clear of “sound enhancements”, the BBE suite is exceptional. The EQ settings are widely adjustable and powerful, the BBE bass boost seems to do a great job of boosting the bass without all the added distortion of many systems and the compressed music enhancement (MP Enhance) is quite effective at bringing the brilliance of lossless music back to a compressed track. Finally, the winning feature for me on the Cowons is their stereo enhancement (equivalent to crossfeed in RockBox). This feature replicates in your headphones the effect of listening to speakers. It’s a simple process and doesn’t mess with the source signal and sound quality, but does result in a beautifully focussed stereo image.

The only key sound quality feature missing (which could also be considered ease-of-use) is ReplayGain. The Cowons don’t normalise the volume for you meaning that you may have to regularly adjust your volume from track-to-track and that’s an issue when you try using the volume controls, but more on that later…

Second Place: iPod Video 5.5G – Solid, clean sound with good depth and good detail. The iPod Video is a great no-frills player. I’ve used it with RockBox and also the regular interface. Either way, the natural sound is great and it seems to have more oomph than other players (volume at 85-90% for higher impedance headphones).

The EQ on the iPod is horrid and introduces all kinds of distortion, but I don’t feel it needs equalising if you have decent headphones. It also lacks a quality volume levelling feature in its original Apple guise (RockBox fixes this). The iPods do have the Sound Check feature, but I find it fairly useless and have heard many reports of degraded sound quality from its use.

Third Place: iPod Classic & Sony Walkman (tied) – These players don’t sound the same, but it’s hard to split them based on their differing shortcomings. The iPod Classic lacks depth in the bass and has a touch of harshness at the high end combined with a lack of very high end detail. It also suffers from the same lack of sound enhancements as explained for the Classic (above).

The Walkman actually has an enjoyable sound for a cheap device (<$100), but it can’t match the others in terms of detail and soundstage. That said, the sound enhancements offered are quite good and quite effective. It’s a perfect exercise player for me (i.e. when I want fun sounding music that I’m not listening to for quality).

Size

I’m not comparing the Walkman here because this is about capacity. Very simply, the J3 is the smallest, but not by much. The iPod Classic is next, followed by the iPod Video and the Cowon X7 is easily the largest and quite bulky. All but the X7 could comfortably fit in a pocket, but the X7 would require a bag of some sort to carry around. It fits nicely in the palm when you’re using it, but the X7 is definitely a bit bigger than the alternatives. That said, if you want to match the sound quality of the X7 you’ll need to add an external amp to the iPods meaning that they just got a bunch bigger and have extra cables sticking out… I’ll be doing a post about the pros/cons of external amplifiers soon.

Interface & Ease of Use

The iPods are the easy winners here – that’s just what Apple do – make things easy. There is no doubt that the Apple interface and synchronisation protocols work well. My only complaints are the lack of effective volume normalisation and the restriction to ALAC as the lossless format. Having recently converted my entire library to FLAC, I really don’t want to have to undo it now. RockBox on the iPod Video allows the use of FLAC, but the Classic can’t use RockBox so it’s slightly more limited.

Another bonus for the iPods is the massive range of accessories available. Being able to drop your pod into a dock and have instant, remote controlled music is a great plus and something that no other player can offer without significant fiddling and expense.

The Walkman comes second because it just works. There are limited bells and whistles and the synchronisation with MediaMonkey was easy and painless. It can’t play lossless formats, but with 4Gb capacity and just-above-average sound quality, 320kbps MP3s are fine. The menus are easy and obvious and the buttons are easy to use and well-placed. Perhaps the best thing about the Walkman though is the SenseMe feature which scans your library and sorts them into mood-based groups. The system isn’t quite perfect (it put a slow song into an upbeat category), but it’s a great, quick playlist solution.

I’m a big believer in working with industrial design rather than fighting against it. If it doesn’t work how I initially expect, I take the time to understand it and learn it, but the Cowons are a long way behind in the ease of use category because of some crazy design decisions. Both players have the volume controls on the side down the bottom of the players. When you’re holding the players you’re fingers are nowhere near the buttons so it’s awkward to adjust the sound (and you need to because there’s no volume levelling).

The menus in the Cowons are quite good and you can access all the important settings direct from the “now playing” screen so this is a plus for the Cowons, but it doesn’t make up for the killer…

You can’t auto-sync playlists to a Cowon player!! That’s right, the Cowon X7 will hold 160Gb of your music, but it won’t let you easily transfer the playlists from MediaMonkey (or Winamp or WMP, etc.) to the player. When you do ask the media player to transfer the playlists, they appear in the X7 (or J3), but when you click on the playlist it says “no file”. I’m sure there’s a fix, but from everything I’ve read it’s a manual fix not an automated one – very frustrating and possibly a deal breaker for me.

Customisation & Flexibility

There are a bunch of custom interfaces for the Cowons and this makes them more customisable than the others. Combine this with their ability to sync with any system and play any type of sound or video and you’ve got a very flexible and customisable player.

The iPod Video can run RockBox and that gives it plenty of flexibility. I rate it only a fraction behind the Cowons because RockBox can be a bit unstable.

The Walkman and iPod Classic tie for 3rd place for different reasons. The Walkman can’t play lossless audio, but it can sync with lots of different systems. The iPod can play lossless audio, but only ALAC so they’re pretty even. The iPod might win by a hair thanks to its ability to play lossless and sync with MediaMonkey.

Summary

What’s the player of choice then? For a collection up to 80Gb, I think I’d take the iPod Video, but over 80Gb it has to be the Cowon. The sound from the iPod Classic just doesn’t cut it for this type of premium player. If you have a huge library and need a large capacity player, there’s a good chance you also appreciate the quality of good music.

I’ll be adding a line out adapter and portable amp to my iPod Classic in the near future and will be sure to report back on the results. In the meantime, I actually think the best answer is to have the Classic for dropping into a dock, using in the car, etc. and having the Cowon X7 (or J3 if you want a small pocket-sized option with killer sound) for mobile portable listening direct to headphones.

 

 

 

Understanding MP3s (and other compressed music) – Part 3… Finale

Welcome to the final installment of my 3 part series of posts about the pros and cons of compressed audio. If you haven’t read from the beginning, it’d be a good idea. Here’s a link: Understanding MP3s (and other compressed music) – Part 1

By the end of Part 2 you hopefully have an understanding of the process of compression (i.e. removing sounds that we theoretically won’t hear) and also the impact that this removal has on the overall “picture” created by the sound. For this final part of the article, you need to keep this concept of a musical “picture” in mind because this final concept is all about the hidden magic within the picture, not the individual, identifiable details.

Harmonics

You might have heard of harmonics before. If you’ve played certain musical instruments (particularly stringed instruments), you might have even deliberately created pure harmonics. If you haven’t heard of harmonics, don’t worry – here’s a short explanation.

Anytime you play an instrument that uses a string or air to create sound (i.e. just about any instrument other than electronic synthesizers), you are creating harmonics. Harmonics are the sympathetic vibrations that occur along with the note that you’re creating. Have you ever run your finger around the rim of a glass to create a musical note? That’s the same concept. Your finger running on the edge of the glass creates vibrations. If you get the speed of your finger movements correct, the vibrations you create, match the natural vibration frequency of the glass. As a result, the whole glass vibrates together and forms a beautiful clear note. Different glasses will vibrate at different speeds of movement  and will create different notes as a result. This is the concept of harmonics.

If you were to walk up to a piano and strike the key known as “Middle C”, you would hear a note – just one single note, but that note will have a quality very different to the same note on another piano or on a violin. The reason for this is the creation of resonance and harmonics. To explain this, I’m going to talk about the note called “A” which is a few notes above “Middle C”. I’m using the “A” because it makes the maths easier.

If you now strike the “A” you’ll hear a single note once again. This time, the note will sound higher than the previous “C”. What’s actually happening though is that your ear is receiving vibrations in the ear and these vibrations are moving 440 times every second (440 Hz). However, there are also other vibrations going on and the majority of these vibrations are directly related to the 440 Hz we began with. As the “A” string inside the piano vibrates, it creates waves of vibration. The loudest of these move 440 times per second, but it also creates other waves moving 880 times, 1760 times, 3520 times per second, etc.

Every note created by an acoustic instrument naturally creates these harmonics which go up in doubling increments (i.e. like 1, 2, 4, 8, 16, 32, etc.) Old synthesizers sounded particularly fake because they didn’t recreate these harmonics and the output sounded flat and lifeless. Newer synthesizers create harmonics artificially and have come closer to the sound of the real thing, but there’s still a degree of difference created by the subtleties that can be created by acoustic instruments. A slight difference in strike pressure on a piano, plucking/strumming strength on a guitar or force of air through a trumpet can create a significantly different tone as a result of the different range of vibrations it creates. All of these subtleties are the “magic” that make music so special and exciting.

A quick note: this blog is not an anti electronic music. Electronic instruments (i.e. synthesizers, drum machines, etc.) can create amazing music which is impossible with traditional acoustic instruments. The discussion of acoustic versus electronic instruments is designed purely to illustrate the importance of keeping harmonics where they were originally intended/recorded.

Harmonics, Subtleties & Compression

In reading the section above, you might have wondered why you’ve never heard these harmonics. You might even choose to put on your favourite CD and try to listen for them. You can actually hear these harmonics if you listen carefully, but the key thing to recognise here is that we aren’t consciously aware of them in normal circumstances. The harmonics and subtleties happen “behind the scenes” of the music and are rarely noticed by the casual listener or anyone who is not actively listening for harmonics.

If you now think back to my previous discussion of compression and the removal of sounds that we theoretically don’t hear, you might see the connection. The first things be “compressed” (i.e. removed) are the harmonics and subtle, quiet sounds that create the finest details and tonal qualities of the music. To the casual ear, nothing seems to be missing, but play the same song compressed and uncompressed through good speakers and you might notice a difference that you can’t quite put your finger on. Here’s another visual example.

The following picture is a hi-resolution (1900 x 1200) desktop wallpaper image provided with Microsoft Windows 7. I’ve used it because it has a certain magic about it in terms of its depth and detail.

The next version of that image is at a lower resolution of 800 x 500 pixels (a bit like a lower bit-rate of compression).

Notice there’s a certain level of the “magic” missing from the second image? It’s hard to put a finger on exactly what’s missing, but the image isn’t as instantly captivating and engaging to the eye. It almost looks flatter somehow – less bright and alive.

Here’s one last version at 600 x 375 pixels, making it even lower resolution and stealing more of the “magic”.

Are you seeing a difference? Don’t worry if you’re not. Go back now and take a close look at the textures of the character’s face and the stitching on his costume. As the resolution drops, so does the detail. See it? That’s exactly what’s happening to your music.

Compressed Music in Real Life

Although it’s probably clear by now that my preference is always for uncompressed music (known as lossless music because no detail/information is lost), it’s not always practical. Understanding compression allows you to choose what suits your needs best. Here are some factors to consider when choosing your level of compression (or choosing no compression):

  • How much space do you have for your music on your computer, device hard drive, iPod, etc? You’ll need to use compression if your space is limited and you want to store a large number of tracks. Here you need to weigh up quality, quantity and space. You can consider increasing storage space, decreasing the quantity of tracks or increasing the compression (and therefore decreasing the quality of the music).
  • Where and how do you listen to your music? If you listen in noisy environments, at very low volume (i.e. background music only) or use low quality speakers/headphones then you might as well use slightly higher compression to maximise the quantity of tracks. The noisy environment issue can be overcome with in-ear earphones and noise cancelling earphones, but the other situations generally mean you can afford to sacrifice quality for quantity.
  • How much does it matter to you? After all, you’re the one doing the listening so if you’re happy with music at 128 kbps that’s all that matters. There’s no such thing as a right or wrong level of compression – it’s entirely up to you.

The best way to decide is actually quite simple. Take a well-recorded track (or two) that you really like and use your music player (iTunes, Windows Media Player, etc.) to compress it in different ways. Next, listen to the different versions on your favourite headphones and/or speakers and decide what you’re happy with. Way up the differences you noticed between the different levels of compression and think about how much space you have to store music and then make a decision.

Summary

Compression is a fantastic tool for portable audio and convenience, but if you have no significant space restrictions, I highly recommend sticking with lossless audio (either Apple Lossless Audio Codec – ALAC, Free Lossless Audio Codec – FLAC or Windows Media Audio 9.2 Lossless). You never know when you might upgrade your speakers or headphones and even if you can’t hear a difference now, you might be amazed at the benefits you get with that next pair of speakers or the next set of headphones! Don’t give up the magic of the music unless you absolutely have too!

Understanding MP3s (and other compressed music) – Part 2

Welcome to Part 2 of my series of posts about the pros and cons of compressed audio. If you haven’t read Part 1, it’d be a good idea. Here’s a link: Understanding MP3s (and other compressed music) – Part 1

Wielding the Eraser

I explained in Part 1 that compression means pulling out sounds that we won’t actually hear, but think about this… The music is like a painting that we “see” with our ears. Compressing music is the equivalent to taking an eraser to the Mona Lisa. It’s like saying, “No-one will notice this brush stroke of stray colour or this tiny bit of shading.” Perhaps that’s true and, to a degree, no-one would notice, but at some point the whole painting’s just going to lose something. It’ll lose a little bit of soul. Sure, you might not pick exactly which parts are missing, but you’ll know something’s not right. Here’s an example:

Notice how the sky in the second image looks unnatural and full of lines? That’s because the process of compressing has removed some of the subtle shades of blue and replaced them with wider bands of other shades. For example, let’s number the different shades 1.1, 1.2, 1.3 and 1.4. During the compression process we would replace shade 1.2 with a second band of 1.1 and replace 1.4 with a second band of 1.3. Now that blue sky would be made of bands of shades 1.1, 1.1, 1.3, 1.3. You can see the evidence of this above in the second image.

So looking at the example photos, it’s clear that they’re both the same photo, but if you had to choose one to print and frame, I’m guessing you’d choose the first one because it’s closer to real life and therefore more pleasing to the eye. The same goes for music.

Think of music as a complex bunch of vibrations making a particular range of patterns. Any little detail you remove from those vibrations will permanently alter the overall “picture”. You’ll still recognise the sound or the song, but it won’t actually sound identical to the original.

Let’s talk about the ear again. Remember my description of how we hear? The ear perceives music like the eyes perceive a painting. You take it all in at once, you don’t pick out a particular colour here and a particular texture there, you just see it as a picture. When we compress sound we permanently alter the “picture” as if we had taken to it with an eraser. To our ears, the result is no different to the photo above on the right. It might not be as dramatic (depending on the level of compression), but it’s essentially the same. You don’t notice a loss of individual sounds, you notice a loss of overall quality and realism.

Here’s one final visual version to show you what I mean. The following charts are spectrograms that show sound as colour. The darker the colour, the louder the sound and the higher up the colour appears, the higher pitch the sound is. A bass guitar shows up down the bottom while a violin shows up further towards the top. There are 2 lines in each chart – these are the left and right stereo channels.

Spectogram - lossless

"This is How a Heart Breaks" - no compression

"This is How a Heart Breaks" - moderate compression

"This is How a Heart Breaks" - mid-high compression (128 kbps)

Notice the density of the yellow and orange colours reduces as you get more compression? The more blue you see, the less of the musical “picture” is still intact. You might also notice that there is more variety and clarity in the colours on the top chart and the colours all get more “blurry” as you move down the charts. That’s the effect of averaging things out. If you look at the first spectrogram and then the second, you might notice that the second one looks like a slightly out-of-focus copy of the first one.

By the time we get to 128 kbps, nearly every high frequency sound is removed. That’s because we lose those hearing at these frequencies first and are less likely to notice the missing sound… or at least that’s the theory. The key thing to notice here is that the musical pictures are different. This is the most visual representation of sound that I can provide and it illustrates exactly how the musical “picture” is gradually erased by compression.

In the Final Installment

Now that you know how we perceive sound and how compression works, you’re all ready to read about why compressed music loses its “magic”. In Part 3, I’ll explain a bit harmonics and their role in creating the soul of the music. I’ll also sum up what this all means when it comes to choosing the level of compression that’s right for you.

As always, I hope you’re enjoying this information and I welcome any feedback or questions you might have.

Ready for Part 3?

Understanding MP3s (and other compressed music) – Part 1

Introduction & Context

As a music lover, I want to experience my music in its purest form. The true purest form is live performance, but we can’t always be at concerts so someone created recorded music. Then someone realised that you can’t take a record player or CD player wherever you go so they created compressed audio. There are many different compression formats including MP3, Microsoft’s WMA, Apple’s AAC, Sony’s ATRAC, and Ogg Vorbis. They all have different names and slightly different methods, but the overall concept is the same.

My aim in this series of posts is to explain what happens when you turn a CD into an MP3 or similar compressed format. In most cases, if you put a CD in your computer, PlayStation, Xbox, etc. and “rip” that music to a disc drive or portable music player, there’s a very good chance the music’s been compressed.

Just like it sounds, compressing music is all about squishing the same length of song into a smaller amount of data. A music track of about 3 minutes 30 seconds takes up between 20-30Mb as pure uncompressed audio. That same track can be compressed at “high” quality to about 7Mb. That’s a massive reduction, but you might be wondering what you’re losing to get the file to shrink by two thirds. Over the next few posts I’ll explain the process and the pros / cons of compression in a simple, real-world way so don’t worry if you’re not technically minded – you won’t need to be.

I should add that I’m not a fan of compressing music, but I recognise the need for it if we want portable music so the overall theme of these posts is to understand what you’re sacrificing when you choose compressed music. Once you know what you’re giving up, you can make an informed decision about what you’re willing to sacrifice in order to carry those extra songs. I hope the information is helpful and interesting.

Key Concepts

The Physics of Hearing: To understand the impact of compression you need to understand how we hear sound. The process begins with a sound source (like a musical instrument) that creates vibrations in the air.  These vibrations travel through the air until they hit our ears. Inside our ears is a thin layer of skin that we know as the ear drum. When the vibrations hit the ear drum, it is pushed around and vibrates in time with the incoming sound. Behind the ear drum are some small bones and our inner ear. The bones get pushed by the ear drum and they vibrate accordingly. As the bones vibrate, they continue to pass the vibrations to our inner ear. You can think of the bones in your ears like the string between two tin can telephones – they just carry a simple vibration.

The inner ear receives the vibrations next and the vibrations “tickle” a bunch of nerves which translate the vibration to a new type of signal for our brain. Don’t worry about the final signal to the brain though, just think about the vibrations until they hit the inner ear. These vibrations are chaotic. They aren’t clear and defined with separate little vibrations for the drums and another set of vibrations for the guitar and another set for the singer, etc. No, the vibrations all pile up and create a big mess of vibration.

A single, perfect note looks like this:

Sine Wave Graph

A graph of a perfect note

This type of vibration is impossible to create with a musical instrument (other than a synthesizer) or voice. Here’s the type of vibration created by instruments and voices:

Music Wave Graph

A graph of musical vibrations

Notice the mostly chaotic nature of the vibrations? There are definitely patterns there, but it’s a big mess of different vibrations. What this graph shows us is how our ear drum would move when receiving this music. The higher or lower each line is, the more our ear drum moves. Lines towards the top push our ear drum in. Lines towards the bottom pull our ear drum out. These movements are all tiny (if the music’s not too loud), but enough to send these crazy vibrations through to our ear nerves. The miracle of hearing is that our brain translates this crazy bunch of vibrations into beautiful melodies and harmonies.

Masking: The second key concept to understand is the concept of masking. Masking is the effect of a louder sound making it difficult to hear a quieter sound played at the exact same time. Think about having dinner in a busy restaurant. You might find it difficult to hear what your friends are saying because of the noise in the restaurant – that’s masking. The combined noise of everyone else’s conversations are masking the voice of your friend across the table.

When some clever bunnies wanted to create a way to store music on computers and iPods (or similar devices) they needed to take some data out of our music. The only data in our music is sound, so they had to find a way to take some sounds out of the music. Sounds tricky, yes? That’s where masking comes into play.

Studies showed that people don’t notice when certain individual sounds are removed from the overall musical landscape. In basic terms, if two sounds occur simultaneously, the quieter one can be removed and we don’t really notice. That’s a slight over-simplification, but it sums up the concept. There are very complex mathematical algorithms and formulas that help determine what sounds will and won’t be missed. I don’t even pretend to fully understand those algorithms so I won’t try to explain it. It also doesn’t really matter how the maths works because the key information to understand is that compression involves removing small pieces of the music that you won’t miss (in theory).

End of Part 1

That’s the end of the first section. Hopefully now you understand how we hear and how masking works. In Part 2 I’ll explain how that knowledge applies to compress sound and how it affects what we hear after the compression is done.