ABX Just Destroyed My Ego, My perception of my bitrate needs was greatly inflated. Options

[dpaint4]

Recently I purchased some intensely expensive (to me) Grado cans. I've archived all my discs via EAC directly to FLAC, and have been shopping around for a portable format that suites my (supposedly) superior ears.

I received an iPod for Christmas, and had recently bought an iAudio X5 for myself so I could take Vorbis on the road with me.

So my tests were supposed to help me decide between using Lame 3.97b2 as my format for both platforms, or iTunes AAC for the iPod, or alternatively ditching the pod for the X5 and using AoTuv Vorbis.

I've been majorly torn between platforms and lossy formats.

So today I set up an ABX test using my Grado headphones and my laptop.

I was going to transcode my FLAC source file to each of the above formats at various bitrates and let the best (to my ears) win.

But my test stopped short when I COULD NOT EVEN ABX BETWEEN THE FLAC FILE AND AOTUV VORBIS AT 64kbps!!!!

You have no idea what that did to me. I am so embarrassed to post it here, but on the other hand, I think I should because there are possibly many folks out there who, like me, ASSUME that they have golden ears, when really the truth is less than flattering.

Of course, AoTuv is fabulous. I already knew I loved it, but it still hurts when you're the type that assumes you need the latest LAME at high variable bitrates and then tell yourself that you still prefer the FLAC files. I'm the guy who wouldn't touch a 128kbps AAC file. Wake up call for me I guess.

[ryran]

ROTFL! =D
That's classic dude.

it still hurts when you're the type that assumes you need the latest LAME at high variable bitrates and then tell yourself that you still prefer the FLAC files. I'm the guy who wouldn't touch a 128kbps AAC file.

Hmmm. That's me. I've been meaning to do some ABX testing for ages and ages... I never have. You've inspired me though. I'm gonna set aside some time this week.

Perhaps we should start a group. Non-ABXers Anonymous or something... hah.

[dpaint4]

Perhaps we should start a group. Non-ABXers Anonymous or something... hah.

Totally. I always just assumed that the tests were for 'those other people' who weren't yet sure of their awsomely perfect ears.

[Hollunder]

Well, I just realised yesterday that I have a hard time hearing things above 14 Khz. The only thing I did was listening to some samples of 3 seconds with diferent lowpass filters applied.

Well, I think that means that my ears aren't golden, flac would be be senseless for me in terms of quality but it still offers the possibility to do whatever I want to without any loss acoustical and data.
So that's my reason for using flac at home.

[quas]

Yeah, I had a similar experience after getting my KSC75s. I'd always told myself that I couldn't ABX low-bitrate mp3s because of my cheap stock mp3 player earbuds. After getting my new headphones, I was surprised to discover that I couldn't ABX lame v7!

I'd like to think it's because of my poor audio equipment/listening environment, but that only counts for so much. I honestly doubt I'd be able to ABX most of my music at v7 under optimal conditions. Maybe it takes practice (which I don't have) to be able to identify audio artifacts.

Or maybe my ears just suck.

[sld]

dpaint4, what's your laptop's soundcard? A better external soundcard may help, unless the existing one is from m-audio or something.

[Gambit]

I think the reason is in large due to the common misconception that audio compression heavily alters the sound. Less dynamics, weaker bass and all those other descriptions "audiophiles" like to throw around, and that in fact are nothing more than just placebo. But in reality, the artifacts are much more subtle, and often require actual training for an inexperienced user to be able to hear them. So when somebody tries an ABX test for the first time, without previous training the results are most of the time surprising.

But I would say that sometimes it's not really a good idea to train for compression artifacts. I guess in this case you could really say that ignorance is a bliss. Enjoy your music and forget about the golden ears.

This post has been edited by Gambit: Jun 13 2006, 22:00

[gameplaya15143]

So my tests were supposed to help me decide between using Lame 3.97b2 as my format for both platforms, or iTunes AAC for the iPod, or alternatively ditching the pod for the X5 and using AoTuv Vorbis.
.......................
But my test stopped short when I COULD NOT EVEN ABX BETWEEN THE FLAC FILE AND AOTUV VORBIS AT 64kbps!!!!

Looks like we have a winner!!

You might consider getting rockbox for that ipod and use vorbis on it too

[Pio2001]

Don't forget also that lossy codec have greatly improved during the last years.

[Waterfall]

So today I set up an ABX test using my Grado headphones and my laptop.

Hey man! What if the sound card sucks??? You still have a chance of having golden ears!

[mdmuir]

Don't feel too bad. I failed miserably in the last 128 kbps test-all were 5.0's to me. This led me to conclude that we probably do not need bother to run that test again-I can only imagine the codecs continuing to improve from this point onwards.

With that said, I still store all my music as flacs, and then lossy encode from those on the fly for whatever purpose. Much easier than digging out cds-and I can encode to any format as needed.

[Alex B]

But my test stopped short when I COULD NOT EVEN ABX BETWEEN THE FLAC FILE AND AOTUV VORBIS AT 64kbps!!!!

In Sebastian's 128 kbps test Vorbis was near transparency at -q 4.25. I personally had great difficulties to make any difference with the reference files. With many types of music Vorbis has excellent quality already at -q 1.5 (check this thread out: http://www.hydrogenaudio.org/forums/index....showtopic=39233).

However, it is easy to find music samples that make Vorbis suffer at -q 0. For example:

http://rarewares.soniccompression.com/test...les/chanchan.wv
http://rarewares.soniccompression.com/test...es/kraftwerk.wv
http://www.mp3-tech.org/tests/aac_48/samples/sample12.zip (Liszt_in_B.flac)
http://www.mp3-tech.org/tests/aac_48/samples/sample13.zip (orion_ii.flac)

Encode the files at -q 0, ABX and hopefully you'll get some of your ego back.

Here are my results (aoTuVb4.51, -q0)

CODE

foo_abx v1.2 report
foobar2000 v0.8.3
2006/06/13 23:16:41

File A: file://E:\test\Vorb_Q0\chanchan.wv
File B: file://E:\test\Vorb_Q0\chanchan.ogg

23:16:42 : Test started.
23:17:22 : 01/01 50.0%
23:17:39 : 02/02 25.0%
23:17:49 : 03/03 12.5%
23:18:04 : 04/04 6.3%
23:18:12 : 05/05 3.1%
23:18:19 : 06/06 1.6%
23:18:27 : 07/07 0.8%
23:18:45 : 08/08 0.4%
23:18:53 : 09/09 0.2%
23:19:05 : 10/10 0.1%
23:19:08 : Test finished.

----------
Total: 10/10 (0.1%)


foo_abx v1.2 report
foobar2000 v0.8.3
2006/06/13 23:22:46

File A: file://E:\test\Vorb_Q0\kraftwerk.wv
File B: file://E:\test\Vorb_Q0\kraftwerk.ogg

23:22:48 : Test started.
23:23:16 : 01/01 50.0%
23:23:23 : 02/02 25.0%
23:23:31 : 03/03 12.5%
23:23:38 : 04/04 6.3%
23:23:46 : 05/05 3.1%
23:23:56 : 06/06 1.6%
23:24:03 : 07/07 0.8%
23:24:26 : 08/08 0.4%
23:24:35 : 09/09 0.2%
23:24:43 : 10/10 0.1%
23:24:45 : Test finished.

----------
Total: 10/10 (0.1%)


foo_abx v1.2 report
foobar2000 v0.8.3
2006/06/13 23:28:22

File A: file://E:\test\Vorb_Q0\Liszt_in_B.flac
File B: file://E:\test\Vorb_Q0\Liszt_in_B.ogg

23:28:24 : Test started.
23:29:10 : 01/01 50.0%
23:29:20 : 02/02 25.0%
23:29:27 : 03/03 12.5%
23:29:37 : 04/04 6.3%
23:29:49 : 05/05 3.1%
23:29:56 : 06/06 1.6%
23:30:16 : 07/07 0.8%
23:30:24 : 08/08 0.4%
23:30:34 : 09/09 0.2%
23:30:41 : 10/10 0.1%
23:30:43 : Test finished.

----------
Total: 10/10 (0.1%)


foo_abx v1.2 report
foobar2000 v0.8.3
2006/06/13 23:32:29

File A: file://E:\test\Vorb_Q0\orion_ii.flac
File B: file://E:\test\Vorb_Q0\orion_ii.ogg

23:32:31 : Test started.
23:32:54 : 01/01 50.0%
23:32:58 : 02/02 25.0%
23:33:01 : 03/03 12.5%
23:33:05 : 04/04 6.3%
23:33:08 : 05/05 3.1%
23:33:11 : 06/06 1.6%
23:33:15 : 07/07 0.8%
23:33:18 : 08/08 0.4%
23:33:22 : 09/09 0.2%
23:33:28 : 10/10 0.1%
23:33:29 : Test finished.

----------
Total: 10/10 (0.1%)

[AstralStorm]

Exactly, at 128 kbps modern codecs (like newest LAME, Vorbis AoTuV, Nero AAC) are quite good.
(Exception: Harpsichord lover? Ditch lossy! ;-) )

The major giveaway with 128 kbps MP3 for me is the lowpass at ~16 kHz, hard to detect. Removing it brings other artifacts. Of course not everyone can hear that and especially not on all kinds of music.
Easier to hear for some are typical underwatery artifacts, warbling, sometimes drop-outs. (sounds like a pop)

While testing Vorbis listen to very slight high frequency boost, metallic quality of sound, roughness. Also look for stereo field distortions (wrong sound positioning, easier to detect with headphones) at low bitrates.

AAC artifacts similarly to MP3, but of course much less. There, the usual most standing out quality is pre-echo (smoothed out sound, ploppy), especially with HE-AAC - low bitrates. Not really bad. No very audible lowpass anymore. At low bitrates with HE-AAC you should easily be able to detect the difference in high frequencies due to SBR. They sound artificial.

1. "Practice, the master of all things."
2. "Ignorance is bliss."

This post has been edited by AstralStorm: Jun 14 2006, 00:04

[Triza]

I did very little execise so far, but when I do I start with the lowest bitrate. I only use vorbis so this is q=-2. I identify the problems and increase the rate until I cannot find any difference. Generally I can ABX up to q=2 or q=3. Sometimes with problem samples I can even ABX q=4. So it is only down to execise I think.

Regardless I decided that q=4 will be enough for me :-)

Triza

[MedO]

Heh, I got a real confidence boost when someone on the vorbis-dev mailinglist told me

Secondly, for someone with golden ears like yourself, I wouldn't consider q5 to be "high bitrate".

after I reported a problem sample (that was two years ago). I rip my CDs to Monkey's Audio nowerdays, and store them on my PC as Vorbis -q6 (I already knew, though, that this was probably overkill for me).
A few weeks ago I tried to determine what bitrates I really need and ABXed a sample at several bitrates encoded with Lame 3.98a3 and AoTuV b4.51. ABXing 64kbps Vorbis was OK, but 80kbps left me guessing... I didn't try that hard, though. With mp3, the limit with this sample was between 112 and 128kbps. Not so golden, I guess, but it's not too bad considering many people used 128kbps mp3 for years with older encoders.

This post has been edited by MedO: Jun 13 2006, 23:53

[xequence]

I dont know if I could tell lossy from lossless or anything, but I want as much lossless as I can hold on my hard drive. I dont know, I just like knowing all the data is there.

[esa372]

...I COULD NOT EVEN ABX BETWEEN THE FLAC FILE AND AOTUV VORBIS AT 64kbps!!!!

Welcome to the humbling world of true perception, my brave friend...

[Ruby]

I think I'm the winner here, in our last codec test lab session at uni, I could not tell a higher bitrate gsm codec thingy from the original... Though, must admit that massive hangovers and Britney Spears don't exactly help with ABX

[Veej007]

i'd get in on this action, but i don't have the patience for foobar and its abx comparator.

anybody know of a gui abx program for dumbasses?

This post has been edited by Veej007: Jun 14 2006, 01:35

[Khushrenada]

i'd get in on this action, but i don't have the patience for foobar and its abx comparator.

anybody know of a gui abx program for dumbasses?

foobar2000

[Lyx]

Though, must admit that massive hangovers and Britney Spears don't exactly help with ABX :D

Thats normal. It cannot sound much worse, even if you encode it lossy.

[dpaint4]

dpaint4, what's your laptop's soundcard? A better external soundcard may help, unless the existing one is from m-audio or something.

I'm absolutely sure that my laptop has some kind of integrated sound thing. It's seriously not high end. But I don't think I can hide behind that excuse. Certainly my laptop sounds as good as my iPod or my X5. And it's better than my last computer which had awful ambient noise. This one is at least silent when it's supposed to be.

[ShowsOn]

I think the reason is in large due to the common misconception that audio compression heavily alters the sound. Less dynamics, weaker bass and all those other descriptions "audiophiles" like to throw around

My 'favourite' descriptive term is "watery", as in, "all MP3s sound watery". Not only is this a generalisation, but I have no idea what "watery" means.

Don't forget also that lossy codec have greatly improved during the last years.

A fact that is constantly ignored. Some think just because a file has an MP3 extension it must mean the encoder used to create those files was automatically the same, and dates from about 1998.

This post has been edited by ShowsOn: Jun 14 2006, 05:11

[legg]

My 'favourite' descriptive term is "watery", as in, "all MP3s sound watery". Not only is this a generalisation, but I have no idea what "watery" means.

That's funny, I use the word watery to refer to warbling.

[ShowsOn]

That's funny, I use the word watery to refer to warbling.

Woudln't just saying warbling be better? The problem with "watery" is that it means different things to different people, it isn't a description of an artifact.