Hello all,

My first post here, looks like a very interesting community.

I have only just started into the world of lossless compression, and wanted to get your opinion on this matter.

It does not make sense to my newbie brian, that two lossless compression methods, compressing the same CD, ie Bob Dylan's Modern Times, will result in obvious audio differences.

The Ape seems to be weighted more towards the bass, but has slightly less bright top end. Flac has a brighter sound and a thinner bottom end.

I downloaded both these files, so the original source is not likely to be the same CD, but it seems unlikely that there are audible differences between two commercially purchased CD's

Is it possible that APE and Flac sound different? If so, how.

Thanks
Mark

Think about the meaning of the term "lossless". No loss. No change in data. This precludes the format itself from influencing the sound.

In theory, bugs in decoding can influence the sound, but those aren't fundamental observations about each format. They also tend to be purely theoretical and unobserved.

If you downloaded both files then the likely difference is that one or both were transcoded from a lossy source. There are tools for identifying such files.

here we go again....

lossless=no loss

it is impossible for an ape file to sound different when compared to a flac file assuming they were made from the same source. if they do then you are doing something wrong.

depending on how you are playing tracks back, several things in between could be altering the sound, like EQ, replaygain, resampling. sounds like you have EQ in there somewhere.

Actually, this isn't unlikely at all.

You are right, it does not make sense.



Unless you can unequivically compare files from the SAME SOURCE, the any analysis is well, invalid.

And well, many 're-mastered' cd's have vastly different sound and volume levels which will definately affect how they sound in relation to each other.



Assuming no encoding or decoding errors are introduces somewhere in the process, No.

Hi all
Thanks for your responses.

I am aware of what lossless means !

The new bob dylan is too new for it to be REmastered, and it seems weird for someone to bother re-encoding to a format like ape or flac if their source was some lossy source like MP3.

I've used Burrn, and it has a default setting which has some correction filter applied... I left that default setting on when I burned the ape disk... I wonder if that did something.

Anyhow, I will do further experiments.

Thanks again for the input,

Mark.

You shouldn't make any assumptions about material encoded by someone other than yourself. Even when buying on the CD format, you cannot be sure that the audio came from the same source. I have compilation CDs where the same track appears on more than one CD, and one of them clearly came from vinyl. There are just so many possible ways for the audio to vary between two independent sources. If you want to compare FLAC vs. Ape, then come up with your own reference material and encode the same source to both formats. I wouldn't bother, though, because they will sound the same.

well you may have just tempted me to see if I can hear any differences/artifacts. ;-)

do you know anything about the "Medium Noise Shaping" Dither filter which is set as default in Burrn?

Why would any lossless format have a need for "noise" shaping?

Curious,

Mark.

Don't bother blind testing. If you're on windows, open up foobar, and use the bit-compare feature. It decodes the two files and compares, bit-for-bit, the audio data. If it says it's identical, it is identical. (Hint: it is)

Hi Just Elliott
yeah, id like to do a bit compare, how is it done as the one file is .ape the other .flac.
Whats a foolbar?
Thanks
Mark.

foobar2000 is a very famous music player (the best one), which has it's own section on these forums.

If you have a lossless source you shouldn't use any filters when burning it to CDDA. This way you should get a CD identical to the original.

I believe it compares the individual PCM samples, not the bitstream, so it should work regardless of the source formats.

Wasn't this a special version of foobar 2000 only available at April 1st? Unfortunately i missed it...

i was actually trying to find something out, but it seems this forum is full of children who would rather get kicks feeling superior at other's expense than be helpful.

or am I being unfair?

cheers.
mark.

I think it's quite funny misspelling too. People here are really helpful, but there needs to be some fun too.

Anyway what I would suggest you is to recompress you APE file to flac and vice versa. Then compare them. How do they sound? If there is something wrong in your playback/processing chain, you'll get same result as before. If the sources were different, the recmopressed files will sound just as before.

Yes! Just look at some of my posts to have some fun because of my very bad english. I am definitely not in the position to laugh about someone making typos. But this was simply too funny...

This tends to happen with a large volume of posts from people who fail to do the simplest of research/searching.

Scroll to the top of the forum page, click the hydrogen audio banner: http://www.hydrogenaudio.org/forums/index.php

Scroll down, on the left side of the page is a number of informative links within the 'related sites' section
In particular you may want to read up on:

http://wiki.hydrogenaudio.org/
http://forums.foobar2000.org/
http://www.foobar2000.org/
http://wiki.hydrogenaudio.org/index.php?ti...2000:Foobar2000

Personally, I find foobar a little too involving to use and setup in a user friendly manner, although it is very customizable and has many add ons/plugins/components/etc.

For a more user friendly, but not quite as flexible in some respects, alternative. Try Mediamonkey. You will find more information specific to MM on their support page FAQ, wiki, and forums.

In any case, the whole point of lossless, is save every bit of data. All lossless codecs are in very simplistic terms, equivilent to using ZIP or WINRAR on wave files.

Thanks teknojnky.

I did do a few searches on this forum when I was trying to find out why my two archives sound different, but I am curious to check their bit similarity, so thanks for the pointers.

till later,
Mark.

Your welcome.

I think your are going to find that the bit comparison will show up as different, because they are not from the same source. (insert big DUH here)

If your going to bit compare something, you must do it from encodes of the same source (presumably a clean, error free cd from your own personal collection), not 2 different encodes from 2 different downloads from 2 different times/places.

gotcha,
thanks mate, makes sense

just for my own edification, I will do a comparison between an ape and the original cd.

but would I need to make a .iso of the original cd to compare it to the .ape file?

till later
mark.

Extract a .wav, it will be a more straight forward process than using a .ISO achieving the same result (assuming no errors on extraction, use a secure method!).

Still, it's a pointless test though.

foobar2000 has an integrated CD player/ripper. So I think you don't even have to extract the track from CD-DA to WAV. foobar2000 will probably do it for you. Just select the original CD track and your APE file and run the comparison.

thanks guys... will do.

If I understand correctly, for a successful bitwise comparison not only the source (CD) must be the same, it must also be ripped on the same drive/with the same "drive offset", or on different drives with "corrected" offsets. Check out "EAC (Exact Audio Copy)" for details.

No, foobar2000 should be able to correct the offsets AFAIK.

You do NOT want to apply dither. That changes the signal. The audio won't be lossless if you alter it.

Dither is only useful when you're trying to cram a high-resolution format into a lower-resolution format, where lossless is impossible, and you want to retain as much quality as possible.

If you're using a lossless compression, you don't want to combine any other process, otherwise it won't be lossless any more.

P.S. I've never heard of Burrn, and have no idea what default options for Dither you're seeing.

Hi there mate, thanks for the response, makes sense.
What do you use for burning ape to cd? Nero? What else do people most commonly use?
thanks
Mark.

Burrrn (very free and easy to use) or EAC (which can handle APE directly, if Monkey's Audio is installed).

I can think of two reasons why someone would do it: 1. They need to cheat a ratio requirement by having users download a bigger file. 2. They are trying to stay in a lossless only site and not lose their account. And since we are in prohibited discussion territory now, I will not speculate any further.

Thanks both for the tips/comments.
A.T. best
Mark.