Real deal about mp3 quality. [Archive] - Audio & Video Forums

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Kaboom
10-16-2004, 04:27 PM
Ok, so what's the real deal about mp3? obviously anyone can tell the difference between 64Kbps and CD quality. Fewer people (not talking audiophiles here, just the untrained-eared, average jack) can tell the diff between 128 and CD quality, far fewer can tell the diff between 192 and CD, and i confess i get lost when it goes above 224. So really, where is the point where Mp3 and CD quality are the same? does this never happen because of the inherent limitations of lossy compression?
i must admit i am a vinyl freak, and that i own very few CDs i actually LISTEN to rather than hear. And my equipment is also by no means real HI-FI.
so where does MP3 sound like CD? does it?

Wireworm5
10-16-2004, 07:21 PM
I use to have my music stored at 192 wma. At this level the quality is quite good, but compared to cds I found cds to have better bass. You may also be able to hear some high frequency irritations on revealing systems if your ears are sensitive to that.On not to revealing systems I doubt if the average person can tell any difference even at 160, and that would depend on the type of music being played.
Since that time I've stored my Mp3's at 320kbps but I have not done a comparison to a cd to see if I can actually tell any difference. But in all honesty I don't think my ears could discern a differnce even at 256kbps.

Rycher
10-17-2004, 08:02 AM
MP3's are a compressed format. Regardless of which bit rate you choose to encode in, you will be throwing away up to 70% of the music - information that may not be all that critical when you listen to it thru your walkman or your computer speakers. But once you listen to MP3's thru a good revealing system you will notice that it is NOT comparable to the original CD. I have all my CD catalog as MP3 320k stored on my computer. I have the MP3's streamed over to my McIntosh system for music playback. There IS a difference. Granted it's not a big difference - certainly not enough to keep anyone from listening to the music, but nonetheless it is still there. Some people are more critical than others when it comes to music playback. I record mine at 320k, you can experiment an see which setting sounds better for you.

beachcomba
10-18-2004, 01:52 AM
FLAC and SHN are also great alternatives to mp3. I'm about to convert my cd cataloge to FLAC; with this format it is hard to discern between cd's and FLAC's.


Just google flac if you are interested, it is extremely easy to convert and decode. And it is a MUST when you use your PC to play music to your audio systems.

kexodusc
10-18-2004, 03:49 AM
As Beachcomba mentioned,there are other formats that are better alternatives to the very old MP3 file. While FLAC and SHN were former favorites of mine, I've since turned to the dark side and embraced Microsoft's newest WMA files...to me these sound the best, especially at variable bit rates.
I have never heard an MP3 or WMA file sound as good as CD quality on my stereo system, but at higher bitrates, they do beat the digital music stations I get on my dish...on my cheap computer speaker nothing sounds good, so it's not hard to get "CD quality".
Sometimes I find very little distortion or artifacts in an MP3, FLAC, WMA etc, through headphones, but when playing them through my stereo, you can tell very quickly that imaging and soundstage are severely compromised. I'm guessing here that overtones and frequencies important for timbre are being cut out in the compression process.

beachcomba
10-20-2004, 10:19 PM
I dont really like it when FLAC is said in the same breath as mp3 or wma. Think of Flac like you would about Meridian(spelling?) to DVD-audio; FLAC just packages the music effeicently.

A 50 meg wave file might be compressed by mp3(or wma) to a 6 meg file. As you can tell, thats alot of file that has been cut(usually the good parts). Where as with FLAC, that same 50 meg file would end up being 38-40 megs. As you can, thats alot of space for music information.

kexodusc
10-21-2004, 03:58 AM
I dont really like it when FLAC is said in the same breath as mp3 or wma. Think of Flac like you would about Meridian(spelling?) to DVD-audio; FLAC just packages the music effeicently.

A 50 meg wave file might be compressed by mp3(or wma) to a 6 meg file. As you can tell, thats alot of file that has been cut(usually the good parts). Where as with FLAC, that same 50 meg file would end up being 38-40 megs. As you can, thats alot of space for music information.

Beachcomba...I think you're falling for the same 1 dimensional argument that most proponents of other failed codecs clinged to. The size of the file or amount of compression is irrelevant, the efficiency is what matters. Flac is much larger and doesn't compress as much, but in all honesty doesn't sound much better than lot of newer formats like certain WMA's. And it certainly does NOT package anything more EFFICIENTLY. Nobody in the universe with any technical background would dare suggest it does. While I'd say it's probably better than MP3, WMA does an heck of a job now. And WMA also has a lossless compression format (which is what FLAC really is), at the very least WMA is exactly as good as FLAC, through in the other features and I argue it's far superior.

Keep in mind Mp3 format is over 12 years old and the latest WMA codecs are quite new (a year or two). The newer Mp3Pro format would be much closer to WMA in performance There's much more to the process than discarding redundant information, much is retained. And the key here is being able to accurately extrapolated that which is lost in compression, some formats do this better than others.

Your on the right track in thining Mp3's lose lots of music information when the go from 50 megs to 6 instead of 38 megs. But there's more at work here. Think of it like this...Take any computer file 50 Megs in size and compress it into a zip at 1/2 the size (25 megs) and a rar file at (5 megs). If this file is a program, when it becomes uncompressed again, it will have to revert to the exact same 50 meg size, or it will not function properly. The compression is 100% perfect at restoring the original. Both compress the file, but one makes the compressed file far smaller in size, while retaining all the original information Applying this concept to audio, that means the original wave form would be restored 100% accurately. At 65-81% of the original file size, FLAC is not the best lossless compression by a long shot.

Now because most codecs incorporate a method of discarding redundant or unecessary information, 100% restoration is highly unlikely. However, there is a point where the human brain is incapable of telling a difference. I don't know exactly where this is...it certainly isn't at the 128 or even 192 Kb/sec Mp3 rate. 192 Kb/sec wma's are very good.

Then there's tons of other factors. Variable bit rates help tremendously too.

I hope this helps clear things up for you.

beachcomba
10-22-2004, 03:36 PM
yea, this does clear a great and many things. I have not been keeping up with MS current run to monopolize the codec feild.I guess I'm just an open source kinda guy. long live FLAC! :D

kexodusc
10-23-2004, 03:38 AM
Well you won't get much argument from me there...If MS starts competing against Dolby and DTS, we're all screwed.

Sir Terrence the Terrible
10-23-2004, 09:04 AM
Well you won't get much argument from me there...If MS starts competing against Dolby and DTS, we're all screwed.

You don't have to worry about that. The film industry loves it's own. That is why it Dts had to work so hard to gain exceptance within the industry. Dolby owned that market for so long, many were just resistant to any change, or newcomers. Besides, as good as Microsoft is, they would have a tough time keeping up with Dts when it comes to innovation in film sound. The already have a lossless digital format that is bit for bit to the printmaster. They have a 10.2 special venue system, and with three or four slaved Dts players for the cinema they could scale a system with as many as 20 channels of lossless data, a control channel for tilting seats, shaking the ground, or cue a light show. They have their bases covered in just about every area imagineable. That would be alot of catch up for Microsoft, not a position they would like to be in.