STOP TELLING PEOPLE YOU CAN'T TELL 192AAC VS LOSSLESS ILL PROVE IT - Page 4

I do not think that trose schould choose the songs himself, if it is so easy to know the difference any song would do...

In fact I think that Febs just schould choose some song and then we could get it on..

I myself can hear the difference between 196 and 320, but 320 and lossless I am not that sure...

http://www.hydrogenaudio.org/forums/...howtopic=39831

Check this thread at hydrogenaudio, looks like someone already has a script written to use an iPod as the testing source.

For me it depends on the song. On my old jazz CDs with analog masters I can tell any kind of mp3 from Lossless, however on 90% of the rest of my music I can't tell any difference between v2 and the original, the remaining 9% I can't tell between v0 and original and the remaining tiny fraction just isn't compressible in a lossy format without problems.


On another note, no one should be encoding at 192 cbr (constant bit rate) It has the double effect of cutting out bits when you need them and wasting them when you don't. 192 vbr (or approximately aps or v2-) will take care of business.

That is exactly what I was going to suggest. If Trose49 insists on doing the test using an iPod, then we have no choice but to use that ipodABX program, as it is the only way that I am aware of to do a proper ABX test on an iPod. It makes it more difficult to ensure that the files are properly level-matched, however.

Trose, I am putting together a list of material that you can choose from. What other genres do you listen to? Recall that the terms of my challenge included testing three songs in separate genres.

Crap can sound very good, if it is lossless...LOL

No it schould be a genre or artist that you are familiar with, but not songs you choose for you self...

It has to be hard...

However I can only tell the difference if I listen really hard for it and know that I have 2 versions of the same song, in a blindtest I'm not so sure..

I think also the frequencies used can have an effect as well, higher frequencies are harder to represent accurately. It's lucky in a way that the human ear is not good at determining the shape of a high frequency waveform otherwise CDs would sound terrible. A 20KHz wave for example on a CD is only represented by about two samples (Not exactly two because of the 44.1KHz sampling rate). This means there is little effective difference between the representation of a 20Khz square wave and a 20Khz sine wave. In practise that doesn't mean a lot since as I mentioned before, we usually can't tell the difference on such a high freqeuncy wave anyway. When you start compressing there is even less data available to represent the waveforms though. The method of representation in the compressed format will be potentially very different but I do not believe it's easy to preserve both the frequency and amplitude of the waveform as well as it's shape, especially at higher frequencies. I used 20Khz as an example, but at any fixed sampling rate the shape of waveform gets progressively easier to represent as the frequency lowers. i.e. it's easier to represent a 100Hz triangle shaped waveform than a 10Khz triangle shaped waveform.

I have not at all investigated the way compression formats represent this information so a lot of this is speculation on my part. It would be interesting to see some plots on an oscilloscope to confirm or deny my thoughts but it does agree with what I hear. In my experience high frequencies and fast changes in dynamics are what are most obviously affected by lossy compression and I believe at least some of these problems are due to changes in the representation of the waveform shape. I have seen some describe lossy files as more synthetic sounding and lacking inner detail and this has been my experience too. This would certainly be the case if the wave shapes were not being represented in the same way they originally were but closer to some ideal sine wave or square wave pieced together by the decompression algorithm. I really should do some proper tests on this sometime since currently I have no proof to offer to back up my thoughts on this matter.

With your setup? Well I wouldnt' be surprised if you did.

Good for you that you can!

How do you legislate for people's individual hearing and source, etc?

Anyway, I can't help you as I am on the other side of the pond You really need someone to help you to do a blind test. No good if you see the file size difference with untagged files say, and make up your mind, even if unintentional

Oh how goes the Village People tribute band thing? (All you have to do is tell me the "secret" and I'll stop! And don't say otherwise it wouldn't be called a secret. Pimping it in your sig like eating double chocolate fudge cake in front of a fitness class)

This is the most rational thing I've read in the entire thread. It's not just ramblings with pink text, and bolded underlined words.

I have the following Spyo Gyra CDs:

Access All Areas
Catching the Sun
Stories Without Words

Pick any song from any one of those CDs and we'll have one out of three!

Some other suggested music to choose from:

Matthew Sweet, Evangeline, Divine Intervention or Girlfriend from the "Girlfriend" CD. (Good recording, with some really great raw guitar sounds. I've used this CD myself for ABX testing).

Larry Carlton, anything from the "About Last Night" CD. (1987 recording that I thought might fit your "blues or jazz" and "guitar" criteria)

How about Steely Dan? I have Aja, The Royal Scam, Countdown to Ecstasy, Can't Buy a Thrill, Two Against Nature, and Everything Must Go. I also have Donald Fagen's Morph the Cat and Kamakiriad.

It's up to you to get this right. I am on the record many times as saying that I cannot distinguish high quality lossy files from lossless. I'll do the ABX myself, but I can already tell you what the results will be!

I don't like the test. The hypothesis should be : can you tell a difference between lossless and lossy?

Your hypothesis for your test is : can you identify lossy vs lossless?

I ascertain that I can hear a difference between lossy and lossless, but telling which one is which is a stretch unless I was the original mastering engineer for the song.

So the test should be :

1. listen to the lossless flac of the song first
2. listen to three random flac's of the song, one is of lossy generation and two are lossless.
3. Identify the odd man out .

This would put to bed the question that lossy and lossless sound the same.