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View Full Version : Still think 320kbp music is CD quality? Here's proof that it's not.




HiFiGuy528
Feb 5, 2010, 11:08 AM
Listen to the podcast here.
http://www.avrant.com/?p=1242

They took a WAV music file, converted to 320kbp and listened to the deletion file to see how much is gone. Then they did WAV to 128kbp and also a double encode file in 128kbp. The difference in all three is huge. Definitely very interesting stuff.



thejadedmonkey
Feb 5, 2010, 11:22 AM
You can skip to about 13:30 into the podcast if you want to get to the meat.

edit: Wow, that's... insightful. Interesting listen to for anyone. A+. why do I feel like i'm writing an ebay review?

zimv20
Feb 5, 2010, 01:05 PM
but can anyone tell the diff in a double-blind listening test? if not...

ChrisA
Feb 5, 2010, 01:34 PM
but can anyone tell the diff in a double-blind listening test? if not...

I find that for most of the time the sound is the same between high bit rate MP3 and WAV.

Out of 1000 seconds of recording 990 seconds will be OK but there will be a few seconds of truly horrible artefacts. It is hard to predict where this will happen but I've noticed it in percussion and electronic music. I think some waveforms just totally "confuse" the MP3 encoders. I've tried both Lame and Franhour (sp?) Encoders.

So a simple A/B test would find that both WAV and MP3 are the same. You need a more extensive test that uses music from different genre and many 100 CDs. In that size sample I find that 1/4th of the CDs will have at least a few seconds of very easy to detect "static" or just weird noises in place of music. Nothing subtle about it. My thinking is that MP3 is designed for compress natural sounds but maybe falls flat in man made sound like square waves or bad studio edits not made on a zero crossing.

I can hear the difference between 128K MP3 and lossless. That is easy. The MP3s loos the sparkle and cleanness. You really need a clean source to notice. The new Beales releases are a good example. The sound is very good uncompressed, impressive I think but if you listen to them at 128K it sounds like the old 1980s release or even worse.

But we are talking about 320K, mostly that sounds good except for a few seconds now and then when it is very bad.

Sdashiki
Feb 5, 2010, 01:56 PM
The only people who care about this kind of argument:

320k! Get a life newbie you need FLAC ALL THE WAY!


Are the people who dont use mp3s but go for OGG, AAC or FLAC. So its a moot point because no one is arguing that 320 is better or as good as FLAC.

Only those who say FLAC is better argue that. Not the other way round. :rolleyes:

And if people do argue that 320 vs FLAC is no different, they arent worth arguing with. Theyve made up their minds.

HiFiGuy528
Feb 6, 2010, 09:16 PM
I bring this up because Steve Jobs said iTunes purchased music is now CD quality at 320kbp and DRM free. It's NOT CD quality IMO.

scottlinux
Feb 8, 2010, 12:10 AM
Transparency. There is a point where lossy compression reaches transparency and the difference cannot be heard by human ears.

http://en.wikipedia.org/wiki/Transparency_threshold

You should check out the hydrogenaudio forums. That website is perhaps the main place for geeking out on this sort of stuff.

If you have access to Linux, there is a program called Baudline which lets you visually see the spectrum of an audio file. It visually lets you see where most mp3 rips cut off right at 13k, curiously enough. (That is not the main point of that program, but it is cool to do.) :)

Comma
Feb 8, 2010, 08:11 PM
There are many, many studies of intensive double blinds on the internet and less than 1% of people can correctly identify the difference between 320kbs MP3 against higher quality music CONSISTENTLY.

I've watched a lot of lectures and read a lot of studies on the subject, primarily due to an interest and a relevance to my potential career, and the material that a lot of lecturers present is solid rather than some person on the internet with his anecdote and just spouting whatever's on his mind.

Nermal
Feb 8, 2010, 08:31 PM
Steve Jobs said iTunes purchased music is now CD quality at 320kbp and DRM free.

Hang on, iTunes purchased music is at 320 now? When did that happen? :eek:

techfreak85
Feb 8, 2010, 09:45 PM
Hang on, iTunes purchased music is at 320 now? When did that happen? :eek:
Nope its not. He has his facts wrong.:rolleyes:

Jolly Jimmy
Feb 9, 2010, 08:22 AM
There are many, many studies of intensive double blinds on the internet and less than 1% of people can correctly identify the difference between 320kbs MP3 against higher quality music CONSISTENTLY.

Personally, I don't think I can hear the difference between a lossless and a 320 mp3 or 256 AAC file. But that's not the point of lossless for me. If I didn't rip in lossless I'd be transcoding lossy files to fit my various devices, making the difference most certainly perceivable.

c-Row
Feb 9, 2010, 08:51 AM
Been there, done that (http://forums.macrumors.com/showthread.php?t=311789). :cool:

pcypert
Feb 14, 2010, 09:13 PM
Here's results from a test Gizmodo ran a while back. Sure some "can" hear the difference, but for most people 256 is a threshold for their gear and ears. Of course the others are better, I'm back to buying CD's and ripping FLAC personally since I got some better speakers and DAC, but for most people and regular use 256 is a good alternative...

Gizmodo Test Here (http://gizmodo.com/5273332/the-great-mp3-bitrate-test-+-results)

c-Row
Feb 15, 2010, 01:26 AM
I prefer my music lossless whenever I am working on DJ sets or mash-ups, so I don't have to reimport them. When you cut, copy, paste and move around audio it's better to rely on the best quality possible.