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Do 320kbps mp3 files really sound better? Take the test

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Re: Do 320kbps mp3 files really sound better? Take the test

#41

Post by rapala »

InclinedPlane wrote: post #35
lmm wrote: post #5

Asking which file sounds "better" is meaningless; some distortions sound good. The proper way to do this is an ABX test, where you compare both to a known original, and ask which sounds more like the original .

The entire exercise is predicated on the notion that if a person consciously listens to an audio recording for a while they will be able to provide a completely accurate estimation of the quality of the recording. To some degree that is true, but I dispute the idea that it is completely true. Yes, there are crazy audiophiles who will tell you that special crystal bullshit gives them a better sound, nevertheless there…

I'm with you on this. But I think that in pop music the vocals have such a high prominence that you kinda miss the song if try to be aware of the "whole song". Especially if English is not you native language. So the brain keeps filtering while you sing along.

In the case of Raise Your Glass, are you referring to the synth sound that "bleeds" through from the background during the chorus?

Re: Do 320kbps mp3 files really sound better? Take the test

#42

Post by raverbashing »

some1else wrote: post #29
andybak wrote: post #21

And the audiophile loons start appearing in the comments: "on high end gear you can hear the difference between a factory and a copied CD.". No. You can't, sir.

Basic DSP knowledge tells us that a digital audio copy is exactly the same quality as the original. Also, testing the difference between 128kbps and 320kbps MP3s over and over again is like drinking warm beer all the time to make sure it's really worse than the cold one.

Thanks so much for your last phrase.

Re: Do 320kbps mp3 files really sound better? Take the test

#43

Post by antonios »

simonbrown wrote: post #38
antonios wrote: post #33

This is meaningless. Statistically meaningful tests are performed using ABX testing methods ( http://en.wikipedia.org/wiki/ABX_test ) with high-quality equipment. And, yes, many people have trained ears (and brains?) that can easily distinguish the artifacts made by the MP3 compression even in 320kbps. See this ( http://listening-tests.hydrogenaudio.org/sebastian/mp3-128-1... ) as an example of an ABX test. As for me…

So if you end up listening to the music with your medium-quality headphones, it doesn't matter whether it's 128kbps or 320kbps.

Yes. For _me_, using _my headphones_, it doesn't matter. Everyone's experience is unique, as it depends on various factors.

Re: Do 320kbps mp3 files really sound better? Take the test

#44

Post by jvdh »

esolyt wrote: post #40

I would argue this song is terrible for this test. I usually can instantly tell the difference between 320 and 128 kbps, but I wasn't able to with this test.

It might be my bad quality headphones, but the song for me was so distorted on the 128kbps that I heard the difference in less than a second.

Re: Do 320kbps mp3 files really sound better? Take the test

#45

Post by lutusp »

ethereon wrote: post #37
lutusp wrote: post #12

Earlier quoted context omitted.

The depth of the sample doesn't get around the Nyquist-Shannon sampling limitation. This means resampling a 44.1 KHz * recording at a higher bit rate is pointless. To be specific, a 44.1 KHz sampling rate provides a bandwidth of 22.05 KHz, period, full stop. http://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_samplin... http://en.wikipedia.org/wiki/Sampling_rate A quote: "The full range of human hearing is between 2…

I believe you're messing up the units here. - The sampling rate, measured in kHz, for CD tracks is 44.1 kHz (not kbps), which determines the frequency range. Nyquist-Shannon applies to this. - The bit-depth, number of bits/sample, determines the SNR of the signal, but has no effect on the frequency range. A typical audio CD has a bit depth of 16. - The bit-rate, measured in kbps, is (sampling_rate * bit_depth * chann…

> The sampling rate, measured in kHz, for CD tracks is 44.1 kHz (not kbps) ...

Yes, corrected, thank you. The original point stands -- the higher resampling rates are increasingly pointless.

> The bit-depth, number of bits/sample, determines the SNR of the signal ...

Yes, and is thought to be the source of the much-remarked, subtle difference between vinyl album music and CD music. But no one knows for sure.

> The bit-rate, measured in kbps, is (sampling_rate * bit_depth * channel_count). So for an audio CD, this would be 441000 * 16 * 2 = 1411200 bps = 1411.2 kbps.

True. Unfortunately, these numbers may motivate people to argue for higher and higher MP3 sampling rates, ignoring the fact that the original temporal sampling rate severely limits the usefulness of these efforts.

Re: Do 320kbps mp3 files really sound better? Take the test

#46

Post by lmm »

lutusp wrote: post #45
ethereon wrote: post #37

Earlier quoted context omitted.

I believe you're messing up the units here. - The sampling rate, measured in kHz, for CD tracks is 44.1 kHz (not kbps), which determines the frequency range. Nyquist-Shannon applies to this. - The bit-depth, number of bits/sample, determines the SNR of the signal, but has no effect on the frequency range. A typical audio CD has a bit depth of 16. - The bit-rate, measured in kbps, is (sampling_rate * bit_depth * chann…

> The sampling rate, measured in kHz, for CD tracks is 44.1 kHz (not kbps) ... Yes, corrected, thank you. The original point stands -- the higher resampling rates are increasingly pointless. > The bit-depth, number of bits/sample, determines the SNR of the signal ... Yes, and is thought to be the source of the much-remarked, subtle difference between vinyl album music and CD music. But no one knows for sure. > The bi…

>The original point stands -- the higher resampling rates are increasingly pointless.

If we were talking about sampling rates it would. But we're not, we're talking about bitrates.

Any MP3 of a CD, whether 128kbps, 192kbps, 320kbps or something else, will still have a sample rate of 44.1kHz. Resampling at 128kHz would indeed be stupid and pointless, and would also result in a much larger file than the original CD. That is not what mp3 does; it takes your 16bits@44.1kHz CD bitstream, and gives you a compressed bitstream that will, when decompressed, give you another 16bits@44.1kHz bitstream which sounds similar. The bitrate measures the size of this compressed bitstream, and therefore gives an indication of how much information (in the technical sense) you must have discarded to form it. But it's entirely unrelated to the sampling rate - you can't even say bitrate = sampling rate * bit depth when we're talking about a compressed bitstream.

Re: Do 320kbps mp3 files really sound better? Take the test

#48

Post by ethereon »

lutusp wrote: post #45
ethereon wrote: post #37

Earlier quoted context omitted.

I believe you're messing up the units here. - The sampling rate, measured in kHz, for CD tracks is 44.1 kHz (not kbps), which determines the frequency range. Nyquist-Shannon applies to this. - The bit-depth, number of bits/sample, determines the SNR of the signal, but has no effect on the frequency range. A typical audio CD has a bit depth of 16. - The bit-rate, measured in kbps, is (sampling_rate * bit_depth * chann…

> The sampling rate, measured in kHz, for CD tracks is 44.1 kHz (not kbps) ... Yes, corrected, thank you. The original point stands -- the higher resampling rates are increasingly pointless. > The bit-depth, number of bits/sample, determines the SNR of the signal ... Yes, and is thought to be the source of the much-remarked, subtle difference between vinyl album music and CD music. But no one knows for sure. > The bi…

> The original point stands -- the higher resampling rates are increasingly pointless.

But the mp3 tracks are not resampled. They use the same sampling rate of 44.1kHz, with a variable bit-depth. So, for instance, a 320kbps mp3 file still has the original sampling rate of 44.1kHz.

Re: Do 320kbps mp3 files really sound better? Take the test

#50

Post by ryandvm »

lmm wrote: post #5

Asking which file sounds "better" is meaningless; some distortions sound good. The proper way to do this is an ABX test, where you compare both to a known original, and ask which sounds more like the original .

Agreed. This is why a lot of audiophiles will swear by vinyl. It's not that they reproduce the sound more accurately, it's that they introduce an artifact that they lovingly refer to as "warmth".
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