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320 kbps MP3 vs. normal audio CD listening Sound quality - Page 7

post #91 of 516
Quote:
Originally Posted by MrMateoHead View Post


I mean, use a high quality, 24-bit, 96 Khz source sample, and re-rip it (always lossless), to a 44.1, and 22.5 khz sampling rate. Then listen for differences. I suspect it would be easier to detect than compression between CD and MP3, which preserves the sampling rate at 44.1 khz.

but at that sampling of 22.5 rate the cut off point is 11.25khz and that is well within the human hearing range eek.gif

post #92 of 516
What soundcard supports 22.5 kHz though? Some support 32 kHz, you could try that.
post #93 of 516
Quote:
Originally Posted by skamp View Post

What soundcard supports 22.5 kHz though? Some support 32 kHz, you could try that.

 

It can be tested by converting the downsampled audio back to 96/24 format, which is recommended anyway to ensure that the DAC/sound card always sees the same rate and format (it normally should not make a difference with any reasonable device, but it is best to minimize the variables in the test). It may also be a good idea to attenuate the high resolution source file by ~1-2 dB to exclude the possibility of clipping in the sample rate conversions.

 

In any case, I would expect the degradation from downsampling to 22.05 kHz to be plainly audible to most people. 32 kHz is more interesting, some (young people with good high frequency hearing) would hear it, but not others. 44.1 kHz is likely only audible in very rare cases at best (it was not to anyone from 50+ subjects in the infamous Meyer&Moran tests). The quantization noise of 16 bit resolution at 44.1 kHz can be audible in quiet passages at unusually high volume levels, but normally not. 16 bits at 96 kHz actually reduce the noise in the audio band, since the total RMS noise remains the same, but it is partly moved into the ultrasonic range (especially with a simple shaped dither).

post #94 of 516

Oh boy were to start this discussion.

This always turns out to be an emotional discussion instead of a technical one.

So I will try to separate both.

The emotional side is the simplest one. The perfect sound is the one you like and it will have nothing to do with how the sound source was made. So philosophically speaking the perfect sound is always the one you like. Your perfect sound wil not be my perfect sound.

 

The technical part of it is more complicated due to how much it has been studied in the last half a century.

It will have to take into account the model used to convert sound into 1010101.

Now these models are hard to comprehend. I can’t fully grasp them, but being in the analytical field I understand modeling.

Most models will grab the information given, source, and straighten the curve to make it easier to store it in less data, saving space and effort. MP3 being the most compressed. Now are these models cutting the sound or mixing it in the upper and lower levels to flatten the curve? the same way we use an EQ? because its essentially the same thing.

I am into quads and much has been talked about the modeling use to separate these channels L/R F/B. The idea doesn’t differ that much.

So the most information that can be recorded from the original master the better. So CD's are great as long as the source and the technical recordings were good and what you play them on are also, but is it better than records, some say no, but then again you need a good set up to play them.

So which of the 3 discussed models are better? Keeping the source the same and the models used are good, the bigger format which is a CD is the best, Does it make a difference to most of us humans, probably not.

But for us humans its all in the way its perceived by each individual. so at the end of the day the perfect sound is the one you like.

post #95 of 516
Compression doesn't use EQ to cut frequencies or flatten out curves. It's much more sophisticated than that.
post #96 of 516

Of course compression is more sophisticated, its a model algorithm used across all types of music.

The outcome is the same when you use an EQ for recording except the reason why you are using it might be different now a days.

In a compression you are getting rid of info that is not required and probably compressing the sound or information. On an EQ you are using to get rid if artifacts in the recording or sound distortion that are due to the source (that’s was one of the usage for EQ or switches for high or low). Now the sources are clean and its use to enhance a specific style of music. But go to early systems of amplifiers/preamps and you will see this was used to get rid of artifact sound being from radio/cassette/turntables. Dolby(C) is an example of this.

The ideas are the same the goal are different.

post #97 of 516
I really don't see the relationships you're making at all. EQ and preemphasis in Dolby are nothing like mpeg compression.
post #98 of 516

...


Edited by anetode - 10/27/12 at 2:22am
post #99 of 516

this feels like a debate about audiophile religon now. science vs personal experience
so but then FLAC reverts back to WAV because of a FLAC plugin that the player has right? so it means it is a exact copy of the WAV when it comes back out, so it should be the exact same, only way to prove this is with a blind test (and computer algoritm... or maths... or physics)

post #100 of 516
Quote:
Originally Posted by streetdragon View Post

this feels like a debate about audiophile religon now. science vs personal experience
so but then FLAC reverts back to WAV because of a FLAC plugin that the player has right? so it means it is a exact copy of the WAV when it comes back out, so it should be the exact same, only way to prove this is with a blind test (and computer algoritm... or maths... or physics)

I'm not sure if it's converted to WAV or just raw PCM, but the way it is compressed the output will be the same as a WAV file. Lossless compression isn't that complicated of a thing really; it's just shorthand code. It still contains the same meaning to it if the program knows how to read it. I'm not sure why people are still convinced that the makers of these lossless formats were lying. I mean you don't see people going around saying you shouldn't throw your music or documents in a zip file. 

post #101 of 516
Quote:
Originally Posted by MrMateoHead View Post

I should add that I don't care if I can't detect a difference - I STILL prefer to buy CDs! Hows that for rational?

I too prefer to buy the CDs for archival reasons, but I rip to AAC (with a target rate of 300K) for listening (iPhone or my old iPod Classic) because to me it is totally transparent. Doesn't seem irrational at all!

In fact my iPod -> FiiO E11 has become pretty much my de facto music source, even when I'm sitting at my computer that has my lossless files on an external drive.
post #102 of 516
Most can probably rip at far lower than 320kbps in any lossy format and not tell the difference from the cd when they're on the road with ipods or iphones. biggrin.gif
post #103 of 516

I recently downloaded Donald Fagens new album(Sunken Condos) from itunes (256k) and immediately noticed inferior sound compared to his last album (Morph the Cat from a 16 bit CD rip). Wondering if Morph was just done better (I doubt it), I next downloaded the 24 bit version(Sunken Condos) from HD Tracks. The difference in sound is not subtle. The 256k version is harsh, brittle, distorted on the low end.

 

But hey, it still sounded good enough for the car at 256k. Moral of the story- whatever suits you.

 

PS- Good new Album (Sunken Condos)

post #104 of 516
Quote:
Originally Posted by jvandyk View Post

I recently downloaded Donald Fagens new album(Sunken Condos) from itunes (256k) and immediately noticed inferior sound compared to his last album (Morph the Cat from a 16 bit CD rip). Wondering if Morph was just done better (I doubt it), I next downloaded the 24 bit version(Sunken Condos) from HD Tracks. The difference in sound is not subtle. The 256k version is harsh, brittle, distorted on the low end.

 

But hey, it still sounded good enough for the car at 256k. Moral of the story- whatever suits you.

 

PS- Good new Album (Sunken Condos)

 

A Double Blind Test is calling for you - FooBar has a built-in ABX. A minimum of 15 trials is suggested.

post #105 of 516

Also, try converting the 24 bit version to high bitrate MP3, Vorbis, or AAC yourself using a good encoder. It could easily be the case that the iTunes version has more "loudness war" dynamic compression and clipping, and sounds worse mainly because of that, rather than the format.

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