Lossless audio - is it really that important? - Yes it is!

[stevei]

Just saw this news article today:
http://www.reghardware.co.uk/2007/04...quality_claim/

The survey it refers to is around 10 years old, but it found that 128kbps AAC audio is, for most people, indistinguishable from CD quality. This means that there would be little advantage in listening to lossless audio vs 64kbps per channel encoded with AAC.

Now, DD 5.1 at 640kbps is over 100kbps per channel, admittedly not AAC encoded, but I would be surprised if it performed worse at this level than AAC at 64kbps per channel.

So I find this hard to reconcile with the claims I've read from people that lossless audio sounds so much better. I've never personally had a problem with the quality of 448kbps DD 5.1. Now I've heard 640kbps DD 5.1 I think it might sound a little bit better, but would be far from certain I could tell the difference in a properly conducted scientific experiment.

If you believe you can tell the difference between 640kbps DD 5.1 and lossless / uncompressed DD, do you also believe you can tell the difference between a 224kbps mp3 and the original CD?

[phranctoast]

I can tell the difference in the music for sure. I think I could at least go up to 360kb/sec, and still tell. You could tell when the volume is higher.

[HDJK]

It depends on your audio setup. If you have nice speakers (in case they are passive, good amps), a room that is somewhat treated and a pair of ears to match your budget, you will definitely hear a difference

[Shin-Ra]

By catering for the people that can tell the difference, with PCM 5.1 to 7.1 audio, a studio pleases everyone.

[stevei]

Another test here:
http://www.geocities.com/altbinaries...l/mp3test.html

Two of the most interesting bits:

"So it isn’t those with perfect hearing, but those that deviate strongly from normal that seem to be especially sensitive to MP3 artifacts. Psycho-acoustic masking effects are at the basis of the MP3 encoding algorithm (the alarm clock goes on ticking even when it rings [but the algorithm doesn’t encode the ticking because it will be masked by the ringing anyway G.]; and the algorithm relies upon such effects also in the case of the generated normalization noises, which in general are supposed to be masked by the useful signals. But when a hearing impairment cause these noises to surface they will be much easier to detect."

So those who can discern a difference may actually have worse hearing than average, which is interesting.

"In plain language, this means that our musically trained test listeners could reliably distinguish the poorer quality MP3s at 128 kbps quite accurately from either of the other higher-quality samples. But when deciding between 256 kbps encoded MP3s and the original CD, no difference could be determined, on average, for all the pieces. The testers took the 256 kbps samples for the CD just as often as they took the original CD samples themselves."

[MatrixS2000]

You can easily test this yourself...rip a cd @ 128K then rip it again at 320K. Give it a listen...my bet is that you will notice a difference between the two and prefer the 320K version.

[stevei]

Originally Posted by MatrixS2000

You can easily test this yourself...rip a cd @ 128K then rip it again at 320K. Give it a listen...my bet is that you will notice a difference between the two and prefer the 320K version.

No, this isn't a scientific way to do the test, you need to arrange a way to have them played to you so you don't know which is which and preferably neither does the person playing them to you.

I once did a blind (rather than double blind) test with a friend where we did this; the person playing them knew which was which but the listener didn't. We could both tell 128kbps from the original but not 160kbps or above.

You could try this test here, though you have to email them to get the answers:
http://www.eclassical.com/eclassic/e...age=blind_test

[coolmilo]

It makes all the difference in the world with Blu-ray movies and music too.

Last weekend I went to headfest (www.head-fi.org). Steve Hoffman, a master engineer (www.stevehoffman.tv), gave a speech about dynamic range. He works in the music industry and has worked with original master recordings and presented audio tracks that he re-mastered. He played a Bing Crosby track from the 1940's and the sound was absolutely amazing. It sounded like Bing stepped out of the grave and was performing live right in front of us. It was a real treat to listen to Steve’s stories.

From there my friend and I ran some experiments that included listening to tracks compressed to 300K MP3, Apple Lossless, and original wav. There sound improvement listening to wav compared to 300k mp3 was night and day.

With respect to Blu-ray, I recommend watching Babel using the lossless track and compare it to the compressed Dolby track. If your sound system is decent enough you should hear a huge difference. I recommend Babel because the acoustic guitar work and overall sound track was amazing. I commented after watching this movie for the first time that it should win an Oscar for the sound recording - and they did. I think I want to say that I liked the move more so for the sound track than the movie itself.

For me, my appeal to Blu-ray is as much for the lossless audio as it is for the improved picture quality. When both are done right it makes for a really great movie experience.

[dobyblue]

Good post cool.

I agree that it's very important. The difference between a Dolby soundtrack and a PCM sountrack is night and day. Far more dynamic range resulting in a much more realistic portrayal of what you're watching.

I find even the difference between a stereo 16/44.1 CD of REM's Radio Song and the stereo 24/192 DVD-A version to be night and day, a real smack in the face.

I loathe .mp3.

[MatrixS2000]

Originally Posted by stevei

No, this isn't a scientific way to do the test, you need to arrange a way to have them played to you so you don't know which is which and preferably neither does the person playing them to you.

I once did a blind (rather than double blind) test with a friend where we did this; the person playing them knew which was which but the listener didn't. We could both tell 128kbps from the original but not 160kbps or above.

You could try this test here, though you have to email them to get the answers:
http://www.eclassical.com/eclassic/e...age=blind_test

LOL - if you want to talk scientific - use science and you would already know the answer to your question!

[MatrixS2000]

Originally Posted by dobyblue

I find even the difference between a stereo 16/44.1 CD of REM's Radio Song and the stereo 24/192 DVD-A version to be night and day, a real smack in the face.

I loathe .mp3.

Yup!

[stevei]

Originally Posted by MatrixS2000

LOL - if you want to talk scientific - use science and you would already know the answer to your question!

I have, by consulting scientific studies that suggest people ought not to be able to tell the difference. I don't think it's valid to compare a DVD-A with a CD, for example, because there's no knowing what differences have been introduced in the mastering process, or how the device is playing back the two formats. Similarly, with lossless tracks on Blu-ray I've heard that some discs have the volume boosted a little for the lossless track to make people think it's punchier. Anyway, I'm quite reassured by the study I gave a link to that found the person who could best tell the difference could only hear up to 8khz in one ear - I'll have to assume that because I can't tell the difference I must have an excellent range of hearing so the perceptual encoding is working for me. However I'm only talking about mp3 qualities here as I don't have equipment that can play the lossless audio from Blu-ray, but I don't see that it should be any different to comparing mp3s vs original CDs.

[shido]

It's all subjective. I for one can tell the difference between a 128kbs mp3 versus a 320kbps one. I'd have to actually hear a lossless track first, though, before I pass a judgment in that area.

[WriteSimply]

Originally Posted by shido

It's all subjective. I for one can tell the difference between a 128kbs mp3 versus a 320kbps one. I'd have to actually hear a lossless track first, though, before I pass a judgment in that area.

Most Sony BDs come with uncompressed PCM and Dolby Digital 5.1 of the original language. You can start comparing now.


fuad

[Deciazulado]

Originally Posted by shido

It's all subjective. I for one can tell the difference between a 128kbs mp3 versus a 320kbps one. I'd have to actually hear a lossless track first, though, before I pass a judgment in that area.

Me too. In one test I did, the "surround" matrix channel from a Stereo (2-channel) recording was full of garbage when playing a center channel only (mono sum) track at 128 kb/s (11:1 compression) At 320 kb/s (about 4:1 compression) it had started to sound clean.

[stevei]

Originally Posted by Deciazulado

Me too. In one test I did, the "surround" matrix channel from a Stereo (2-channel) recording was full of garbage when playing a center channel only (mono sum) track at 128 kb/s (11:1 compression) At 320 kb/s (about 4:1 compression) it had started to sound clean.

You have to be a little careful with these things, though - I once encoded a pro logic matrixed stereo file at 128kbps and it sounded TERRIBLE. At 192kbps it was fine, and I could have easily assumed the difference was due to the bitrate. However, a more detailed investigation revealed that the codec was configured to use joint stereo at 128 and stereo at 192. Switching it to use stereo instead of joint stereo at 128 made the problem go away at 128.

[Filterlab]

Originally Posted by HDJK

It depends on your audio setup. If you have nice speakers (in case they are passive, good amps), a room that is somewhat treated and a pair of ears to match your budget, you will definitely hear a difference

I couldn't have put it better myself HDJK!

[MatrixS2000]

Originally Posted by stevei

Anyway, I'm quite reassured by the study I gave a link to that found the person who could best tell the difference could only hear up to 8khz in one ear - I'll have to assume that because I can't tell the difference I must have an excellent range of hearing so the perceptual encoding is working for me.

If that assumption makes you happy go with it - to me it's a joke.

Think about what it is saying - the person with excellent hearing can't tell the difference, yet the person will impaired hearing can.

Don't believe everything you read on the internet....

[MatrixS2000]

Originally Posted by shido

It's all subjective. I for one can tell the difference between a 128kbs mp3 versus a 320kbps one. I'd have to actually hear a lossless track first, though, before I pass a judgment in that area.

Of course you can, because it is night and day difference.

But of course that means you can only hear up to 8Khz...

So funny what some people take as fact...

[Deciazulado]

Originally Posted by stevei

You have to be a little careful with these things, though - I once encoded a pro logic matrixed stereo file at 128kbps and it sounded TERRIBLE. At 192kbps it was fine, and I could have easily assumed the difference was due to the bitrate. However, a more detailed investigation revealed that the codec was configured to use joint stereo at 128 and stereo at 192. Switching it to use stereo instead of joint stereo at 128 made the problem go away at 128.

You think I don't know what I'm doing? I know what you're doing.


btw I was listening to The Beatles in surround before they ended