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320 kbps MP3 vs. normal audio CD listening Sound quality - Page 3

post #31 of 439
10/17/12 at 5:25am

CD != uncompressed wav. Different storage, different media. Please don't mix up uncompressed file format with audio CD. They're from different storage and media. I said about event comparing lossless file vs CD uncompressed disc not lossless file vs uncompressed file.


Edited by WindowsX - 10/17/12 at 5:27am
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post #32 of 439
10/17/12 at 5:29am

I mean sure they're different, as CD's are encoded in pits and landings and hard drives use magnetic polarities, but the output is identical.

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post #33 of 439
10/17/12 at 5:55am
Quote:
Originally Posted by WindowsX View Post

For evidences, I forgot most places posted years back. Just feeling nostalogic to make some posts in board I was once addicted during head-fi jorney. Try searching for lossless vs uncompressed and you should find people debating with some links and information. I knew too much to make it simple to understand

Thanks, that reminds me of one of my favorite Einstein quotes: "If you can't explain it simply, you don't understand it well enough."

By the same token, allow me to explain why I think you are wrong:
Quote:
Originally Posted by WindowsX View Post

If you check average bitrate of lossless format, you'll mostly see 1411kbps being packed down to 500-800kbps depending on how bits are filled to reproduce dynamics. ... You have 16 bits for each sample to represents dynamic range. Some use 16 and some use even 0. Gap before reaching to 16 will leave room to make lossless compression.

Lossless compression does not result in truncated bits: if 16 bits go in, 16 bits go out. Furthermore, few recordings ever even approach the ~98db dynamic range afforded by 16 bits.
Quote:
Originally Posted by WindowsX View Post

I tried converting 320kbps mp3 to flac and then mp3 again but they're not the same file still when compared with bit transparency check through foobar. You can't randomly cut parts that have data represents dynamic range stored so only solution found is to keep most noticeable parts of dynamic range. Get real ppl. If 320kbps is identical to CD, we don't need 24/192 and DSD format to keep digital mastering.

That's not how mp3 encoding works either. The signal is broken down by frequency bands and analyzed, differences in dynamics are only discarded to account for psychoacoustic modelling of auditory masking. With a good psychoacoustic model at a high bitrate it's not a matter of "most noticeable" but "even barely detectable by ABX". The overall dynamic range does not suffer, which is why your original statement,
Quote:
Originally Posted by WindowsX View Post

CD is better. You can't have 16/44.1 packed from 1411kbps to 320kbps without dynamic compression.

...was flat-out wrong regardless of whether Guttenberg prefers to conflate dynamic compression and lossy data compression in his rhetoric.
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post #34 of 439
10/17/12 at 5:57am

Output data might be identical assuming both have zero errors but I don't think time domain will be the same having different seek time, different layers, different latency, different jitter.

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post #35 of 439
10/17/12 at 5:59am
Say what? What seek times, what layers? How in the world does lossless encoding add jitter? You're just grasping at straws now.
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post #36 of 439
10/17/12 at 6:05am

So does that mean that audio data stored in a SSD or loaded on a RAM disk is superior?

 

rolleyes.gif

 

In audio playback latency makes no difference. It doesn't matter if the data is stored in pits and landings, magnets, or alternating pictures of squirrels; the data is the same and the quality will still be the same.

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post #37 of 439
10/17/12 at 6:34am

Same data at different time domain doesn't produce the same result for real time application. dCS paper can make it simpler to understand. Go read it here.

 

http://www.dcsltd.co.uk/assets/dCS_Guide_to_Computer_Audio.pdf


Edited by WindowsX - 10/17/12 at 6:35am
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post #38 of 439
10/17/12 at 7:09am

A computer is fully capable of reading data off of a hard drive in perfectly timed intervals...that's not really an issue with most modern technology.

 

Might as well say CD's are faulty since simple mechanical hiccups can cause timing issues.

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post #39 of 439
10/17/12 at 7:43am

Not true. It's fallacy believing consumer's modern tech can do anything while dedicated companies like Emm Labs/dCS requiring to buy transport mechanism from Esoteric for their own hiend CD player/transport. Read dCS paper carefully and try to understand how digital plays with time domain. Why linking external masterclock can make changes to transport/dac. How time domain affect digital signal transmission. It's audiophile placebo? This is pure science from digital audio engineering.


Edited by WindowsX - 10/17/12 at 7:47am
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post #40 of 439
10/17/12 at 9:52am
Quote:
Originally Posted by chewy4 View Post

I was unaware of that plugin, I'll have to check it out.

 

While I got it right on the comparison of the two files provided by the test here(only one trial as I was unfamiliar with the plugin, so sue me), it was by no means easy. Had to listen back and forth 5 or 6 times. It does effect certain kinds of songs more though, I'm not sure what the bitrate was of the uncompressed file provided. I'm going to later tonight try with a file that gets compressed at 900+kbps vs a 320 mp3 and I'll share my results.

 

But I think a much more accurate way to see if you can tell the difference would be an immediate switch though, rather than a test that relies on having good short term memory.  

 

OK, so I just tested this. And I noticed that the ABX plugin does do a near instant switch, which is awesome.

 

I used "Happy to See You" by Yppah. 1mbps when in FLAC.

 

Only problem in my test is that even though I set EAC to rip at 320kbps, it ripped at 192. I only ran about 7 trials. I know that is not enough to be scientifically accurate, but I figure after getting 0/5 it was enough proof that I couldn't tell a difference. I might try this more extensively later with more files, or perhaps try listening for longer and more carefully(really only listened to 10 second parts at a time) since I don't have a lot of time now.

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post #41 of 439
10/17/12 at 10:45am
Jitter and time facts and figures are completely meaningless until you relate them to the thresholds of human perception. Once you do that, you realize that all the scientific hand waving is about something that is as much as a hundred times too small to be heard with human ears.
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post #42 of 439
10/17/12 at 11:00am

Another fallacy of 'good enough'. Trying to throw up something to avoid opposing inconvincible facts that MP3 != CD. There's another interesting topic from computer audio here.

 

http://www.head-fi.org/t/631863/why-on-earth-do-people-still-listen-to-mp3

 

This topic should also clear a lot of things for OP as well.


Edited by WindowsX - 10/17/12 at 11:02am
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post #43 of 439
10/17/12 at 11:02am

Quote:
Originally Posted by WindowsX View Post

Not true. It's fallacy believing consumer's modern tech can do anything while dedicated companies like Emm Labs/dCS requiring to buy transport mechanism from Esoteric for their own hiend CD player/transport. Read dCS paper carefully and try to understand how digital plays with time domain. Why linking external masterclock can make changes to transport/dac. How time domain affect digital signal transmission.

I tried reading the dCS paper carefully, but as I already know both how to use a computer and how a DAC works I'm not really feeling like the target audience. However some previous readings have enlightened me to two fascinating protips: 1. in every modern audio application and OS there's a series of buffers; 2. in every modern DAC there's a PLL. At the time that computer I/O and DACs were thought up we were fortunate enough to have engineers who were aware of the existence of a time domain so they came up with these two nifty little gadgets to maintain a steady stream of data and correct for inbound jitter, respectively.
 
Now I have nothing against the engineering in dCS's 10-20,000$ DACs, nor their 10,000$ clocks, nor their suggestion to devote 4+ gigs of RAM for an audio buffer and not even their advice to spend 200$ on an iTunes plug-in. On the contrary, I am rather impressed by their business acumen. But I'm nonetheless aware from theory, tests, measurements and personal experience, that a modest buffer of a few seconds of data and a stock PLL/stock oscillator will result in the same exact ultimate result: jitter at a negligible level. And while the threshold of the audibility of jitter and novel clock locking or regeneration methods are themselves fascinating topics, I'm also aware of the plain and simple fact that neither lossless nor lossy compression make any difference whatsoever to jitter in modern computers. Now you might experience laggy system response, underrun or an OS memory error or some such, but the result will be an audio drop-out or an audible pop, not a persistent difference in dynamic range. (Unfortunately there's no special setting and no expensive audio equipment which will lead to a guaranteed crash-free Windows or Mac OS experience, nor is any mechanical disc transport free from eventual failure)
 

Quote:

Originally Posted by WindowsX View Post

 

This is pure science from digital audio engineering.

 
 
No, that is a user manual. This and this have to do with the science of digital audio engineering.

Edited by anetode - 10/17/12 at 11:04am
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post #44 of 439
10/17/12 at 12:14pm

FYI: dCS is the first company who wrote digital audio upsampling algorithm for mastering use. I know a few more for reading but dCS is quick catch with google search and pretty much good enough for basic explanation. Engineers there know a lot better than a few learning books where specialized experiments and patented information are not shown. I experienced a few masterclocks myself from cheap ones to highest available ones like Esoteric's rubidium clock and I know what I'm talking about and how that affect changes in system.

 

Maybe I shouldn't mix highend stuff in this topic. My bad.....I should stay silent now as mp3 vs cd is already over.

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post #45 of 439
10/17/12 at 12:20pm

Recording and playback are two completely different contexts. Playback is much more straightforward.

 

I'm not sure what you were referring to in the link to the MP3 thread.


Edited by bigshot - 10/17/12 at 12:23pm
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