Entertainment For Lively Minds
Sound quality of MP3 files
I used to rip all my CDs into MP3s at 192kbps. Eventually I realised that I should be ripping at the maximum of 320kbps. I've considered re-ripping the previous CDs even though I couldn't tell the difference between the two. So to put the nagging paranoia about sound quality to rest I conducted a test.
I ripped "Not Fade Away" by The Rolling Stones six times using different kbps. The song was chosen mainly because it's only 1 minute 47 seconds. The CD I sourced it from was the 3CD London Years Singles Collection that was remastered circa 2002. I've also read that iTunes is a bad MP3 encoder so I wanted to test it against the encoder I usually use, Creative MediaSource that came with my Creative Zen Touch back in 2004.
I encoded the tracks as follows:
192kbps Creative MediaSource
96kbps Creative MediaSource
320kbps Creative MediaSource
320kbps Variable Bit Rate Creative MediaSource
320kbps MP3 iTunes
240kbps AAC iTunes
I didn't listen to it as a blind test were I was trying to guess which was which. I checked after about a minute to see what version I was listening to.
The results? They all sound the same. They all recreated the song the exact same, at least as far as I could tell. The song has a slight bit of what sounds like tape damage at the start and there's a millisecond of audio drop out as Jagger sings a drawn out word towards the end. All of them recreated these sounds without any difference. There was a bit in the middle of the song were Jagger seems to be threatening to overloading the microphone. In the 96kbps version there didn't seem to be as big a threat of overload.
I might be kidding myself but I did think that the 96kbps version sounds as good as the 320kbps version. I shall not be re-ripping CDs as it is clearly pointless for me to have better sounding MP3s. The 320kbps VBR files are only about 1,000Mb bigger that 192kbps CBR files so I plan to use those for all my future ripping. AAC is not very Windows friendly so I don't think there's any benefit using it.
Anyone else ran an audio test, or has an opinion about the difference in sound quality between different kbps MP3s?
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Not Fidelity Way
I'd have used a different song for that particular test, LOUD.
The Stones' singles have always sounded harshly recorded to my ears, and it's harshness that I find the most obvious flaw with MP3 recordings.
It would have been interesting to have started with a beautifully recorded piece that has acoustic instrumentation and a full dynamic range with little or no compression.
Maybe someone could suggest a track that really suffers under MP3 compression? Probably not a mid-sixties single mixed for listening through a transistor radio's 3 inch mono loudspeaker. Or even LOUDspeaker.
The first MP3
The first MP3 ever was apparently Tom's Diner by Suzanne Vega. This is an acappella track and was apparently the most crisply recorded vocal performance the computer boffins who created the original MP3 codec could find.
ISTR reading that...
...Apple used Peter Gabriel's 'Red Rain' as their test track when developing the sound sampling and reproduction functions in the Macintosh
an important point
How were you listening to these MP3s? if it was through some ipod earbuds then , no, you're unlikely to tell the difference. If it was through some top of the range Bang and Olufsen speakers then it will be immedietly apparent.
You'd like to think so
But then again: I attended a conference during the original Napster era, and one of the speakers played an mp3 and an uncompressed file of the same song back-to-back over the PA system, without revealing which was which. The audience were then asked which of the files was the mp3.
Only half the people there got it right, which suggests that no-one could really hear the difference. This may have been partly the result of the track they played, but it was interesting nonetheless.
I'd bet
that any really good Blue Note recording, a Rudy van Gelder recorded track perhaps from say, Lee Morgan, would sound pretty ghastly in MP3 form when played back on decent kit.
What usually does my ears in is the horrid smearing of the hi-hat, and that tinny echoey effect that lurks deep in the background, sounding like a constant phasing error.
Except for use on portable players via earbuds on trains, I don't have a use for MP3s, thankfully.
If you want to listen to music on the move, now that RAM and flash drive space are as cheap as chips, I don't see a need for compressed audio at any level of quality below the Red Book CD specification. There would be no need to invent the format today for this purpose. The only apposite use for MP3 encoding is to save bandwidth when accessing web embedded voice or news reportage (Podcasts etc), and there are lots of much better audio compression algorithms to choose from these days. The MP3 standard only remains in use for musical enjoyment because of commercial inertia.
I was listening through
my iPod Classic* using CX300 Sheinheiser in-ear buds. This is my usual set up. There is no point in me testing my MP3 files using equipment I don't normally use. I use CDs for my Hi-Fi when at home (I have played MP3s through it and it sounds good but it's not something I care enough to test).
I should also point out that I'm not an audiophile.
* Anyone else noticed that the menus now have no slow-down as it no longer waits to load the album artwork.
It's your set up that will reveal the quality
If you listen on a revealing set up you should tell the difference. I can between 128kbs and VBR stuff even in the car but also on the home hifi though a line out lead. Its less revealing on the pc and on my ipod, I can with my decent headphones but not really with £30 Sennheisers.
Conference venues almost always have poor audio set ups for listening to stereo recordings. You need 2 speakers, set up equal distance apart from the listener and not too far away. This doesn't happen at a conference so I'm not surprised at the findings there.
I rip at high quality VBR which comes out between 220 and 160kbs depending on the track and this seems to work well for me. They sound better than the 128kbs but I can't tell them from the 320kbs stuff I have bought.
This seems like a good place to ask
Over the weekend my 20Gb Sony Walkman died. I had been thinking about replacing it anyway. Although I liked its looks I had come to realise several problems with it over the last four or five years I have owned compared to an iPod.
The most obvious one is that iPods are so dominant in the market and everything from podcasts to speaker docks are designed to work with them - unlike the Sony.
The SonicStage (iTunes equivalent) software is clunky, resource hogging and unreliable and they don't even sell tunes anymore. This is the main problem. Other family members with iPods seem to find transferring files a lot less labour intensive.
Although it has a rather lovely design where the screen is hidden, you can't read the screen in daylight.
You don't get a display of album covers. Not the end of the world, but I'd like to see them.
So here are the questions. Do I bow to the inevitable and buy an iPod (probably the classic 120Gb - I like the look of the iTouch but think I'll probably run out of space)? Or are other manufacturers offering products with the ease-of-use and compatibility. Or do I buy a new version of the Walkman? One of the things putting me off an iPod is that I will have to re-rip all my CDs as Sony use a proprietary ATRAC format (unless someone knows how to convert these to MP3).
Any help appreciated.
iPod Classic is a very good machine
I would recommend it. I would doubt you would be disappointed with it. I've had mine for about five months and I'm delighted with it. So far no problems etc. I wouldn't consider any other machine.
Sadly the ipod is the only option
For two or three years I used an Iriver which, two or three years ago, was superior to the ipod. However the ipod got updated and the iriver didn't. So in the end when I needed more space I looked around and discovered that no-one is making anything anywhere near as useful as an ipod. It's a shame because I'm sure there's lots of great stuff that MP3 players can do but nobody seems to be innovating much.
The one downside
with the Sony Walkmans is that they have yet to sort out "gapless playback".
Creative Labs - Zen Vision M 60Gb
I may not be a fan of MP3s, but when I'm stuck on a train looking out at the same trackside scenery day after day, my Zen helps keep me sane.
It's good for 320 kbps music, and with decent in-ear thingamajigs, makes a din I can put up with for an hour or more. The screen is very clear and bright, and I can recode movies ripped from DVDs or other sources to 320 x 240 size using Open Source software. There's also an FM tuner built-in, though that doesn't work very well inside trains.
It's quite a chunky little devil, about the same size as 20 Marlby Lights, so you can't jam it into your jeans pocket easily, but other than that I'm extremely impressed with it.
This looks interesting...
...especially as it supports both FLAC and FLV.
http://www.lightinthebox.com/Newsmy-4GB-262k-Color-QVGA-TFT-LCD-MP4-MP3-...
Personally...
...I can usually tell the difference between 128k and 320k mp3s on a decent stereo (QUAD 33/303 amps and ESL57 speakers). I couldn't tell the difference 'twixt 320 and 1411k so decided to rip my music into 320kbps mp3.
Acoustic music tends to show up the differences best. It hardly matters much when you're listening to My Bloody Valentine
...or...
...anything recorded before 1960.
I find Oasis
better at 60kbs and with the volume set at 0......
and
my headphones unplugged (just in case).
and
while I'm asleep, or on holiday on another continent.
Have you ever considered...
...getting out once in a while?
Yep
Followed through on it and thoroughly enjoyed myself. May even do it again soon.
MP3s in clubs
Speaking from personal experience, it's all too obvious when DJs are playing MP3s in nightclubs. At that volume, the sound of the high end - especially the cymbals - can be physically painful. I'm amazed people don't run away screaming.
That said, I think you can get away with 320k MP3s in clubs, and sometimes lower. Depends on the song.
Totally agree
about the splashy mess MP3s make of decently recorded top end percussion transients. Ghastly.
WMA
I find MP3 at 96kbps are fine but at 64kbps it starts to lose something. However, I find for the purposes of my Creative Zen, converting soungs to WMA 64kbps is fine and sounds clearer to me than a low bit rate mp3. I don't really know why, I've heard it's a more complex type of compression and that it takes a little more battery to convert back into sound, but aside from that I couldn't tell you.
WMA and AAC
are comparable to an MP3 encoded at a higher bit rate.
WMA or AAC encoded at 128 is comparable to a MP3 encoded at 192kbps.
Thanks
That makes sense to my ears.
Another sound test
“Red Rain” by Peter Gabriel. I chose this song based on Stimpy’s recommendation above.
Ripped from the 2003 Hits Best Of CD at 320 and 96kbps CBR MP3.
Transferred to my iPod and two playlists created with the two tracks in different orders.
I got someone to choose one of the playlists so I didn’t know what version would play first.
Musically it started fine until the vocals started. There was an unpleasant harsh sound whenever he sang an “s” and when he sang the start of the word “edge”.
I assumed that it was the 96kbps version.
I skipped to the next version. Musically it might have sounded slightly warmer but not enough to be noticeable. Then the same problem with the “s” came up again. Perhaps not quite as bad but still very pronounced. I assumed that it was the 320 version but I wasn’t 100% sure.
My guesses were correct. To be honest though, if 320 had played first I would have assumed it was the 96 version. It’s debatable if I would have changed my opinion when hearing the second track. I doubt it.
I decided to check the original CD. It has the same problem but it sounds right, not like a big flaw. It’s easily ignored as it’s quiet and your attention is not attracted to it.
The opening lyrics:
“Red rain is coming down
Red rain
Red rain is pouring down
Pouring down all over me
I am standing up at the waters edge in my dream
I cannot make a single sound as you scream
It cant be that cold, the ground is still warm to touch
This place is so quiet, sensing that storm”
mp3 vs CD
Having read that, I think you need to get out and enjoy some sunshine, but I admire your dedication.
In the old Napster days I was using mp3 at 128 kps, but now I'm all legit and on iTunes, I encode in AAC at 256 kps and mostly I can tell the difference, but on some modern recordings (i.e. this decade), which in CD format are often highly compressed, I don't think there's much to be gained with higher bitrates.
Enjoy the sunshine whilst it lasts!
I gave the "Red Rain" test
to two others. I didn't tell them who performed the song and they both assumed it was Sting.
FYI: All three of us did this test using our own headphones plugged into my iPod Classic.
Person 1 has a rock band. He listened to the 320 version for about a minute. I then played the 96 version. About eight seconds in, before the vocals even started, he said that it was the weaker version. He said that it sounded muddy and messy.
Person 2 listened to 96 and then 320. He seemed pretty certain that the second version was the better one. He said it sounded slightly more clearer and more detailed. He admitted though that it was a bit of a guess and that he wouldn't have been too surprised if the first version was the better one.
Quality
I went through a similar process last year when I decided to ditch my hi-fi gear and digitise my collection as I really didn't use the kit enough to hang on to it. Even though I still listen to a lot of music, it just wasn't in the "other" room in front of my hi-fi.
The household (although not the FPO, of course as she refuses to admit to any quality differences on principle, even between Standard and Hi-Def TV) listened to the same track (Fall At Your Feet by Crowded House, which has been my reference track for years) at various bit rates. I found pretty clear differences up to 256k as the bit rate increased but 256k to 320k was VERY marginal and we couldn't hear any difference between 320k and uncompressed (this was an ipod classic played through a B&W Zeppelin, by the way)
Testing these blind we could all tell the 128k rips but not everyone could always pick out the differences above that.
The Gadget Show did a blind test last year and the MP3s came out on top, preferred to CDs. A small sample (2 people, actually) but interesting nonetheless.