The difference in the sound produced that you deemed "louder is not because it is encoded at 320, 192 or 128 Kbps or CBR.
Bit rate dictates how close to the original Analog Signal the Digitized Audio will be. http://en.wikipedia.org/wiki/Digital_audio
Volume or Loudness will not be affected. The reason why 320 sounds better than 128 for example is that the Digital Audio Produced was closer to the original source. Sounds Fuller.. Not Louder.
This is also common, sound perception is very subjective, both in quantity and quality. As you grow older, you start losing frequencies and even what you hear, is interpreted differently. If you google, you will find more discussions that say that onboard is the same or impossible to discern unless you use very high quality headphones.
I use headphones most of the time and since i usually encode a DPLII audio track, i bought ASUS Xonar DG, becuase it has Dolby Headphone. Turns out after a day, i disabled the Dolby headphone in the driver, it was so fake. And at the end i went back to onboard audio... I have the card sitting in its box... The only good thing i found is that the Xonar had internal amplifier so it was boosting a lot the audio signal. But i have the headphones connected to a speaker, so i use the speaker's knob to amplify...
It's the same story with people who claim they can tell a 192K mp3 from a 224k from a 320k and from real CD. I don't know, i can't tell the difference. The music can be as digital as it likes, my ears work in analog mode. The soundwave is analog, the meccanism inside the ear that generates the neural impulse is analog... I mean, i don't think people are doing it on purpose trying to fool the others. It's just that not all ears are same. At the same way there is visual acuity, there is also auditory. And also subjectiveness on what sound one likes. You can see in reviews people saying "wonderful bass", another say "too much bass" for the same product.
YES on individual perception. However, true sound men have been gifted with articulate ears. Can distinguish a FLAT sound from a little HARSH sound, PUNCHY Bass from HUMMY Bass. PRACTICE also makes them more discerning.
320Kbps MP3 vs a TRUE CD vs a TRUE Recording Rails? It'd be like saying i3 vs i5 vs i7 for them. You wont notice the difference without being exposed to each of them.
Yes i agree with you.
I noticed the difference between my previous UD5 and the Sabertooth when i played some YouTube songs like this one: https://www.youtube.com/watch?v=tGlGBIzN2ls
Amplification. Audio Output components. Volume differences.
SNR? Kindly elaborate how you can gauge this using your ears.
If you miss a lot of tones from one to another, that's conversion differences and algorithms.
All perception. Not a standard. What audio engineers like to hear is what they'll make you hear. On that perspective, sound measuring devices can give you an idea how your system will sound with reference to Frequencies of the audio spectrum. But without listening, you won't and can't say that it's the best sounding sound the system can produce.
Out of context. 1080P or HD or BR are all Video Quality references. Neither involves how audio is encoded with movies.
Edited by mus1mus - 11/2/14 at 3:15pm