[kevs]

I'm testing different bit rates for converting a music collections I have. I have a pretty good ear and stereo system. I've always heard big difference between cassette tape and cd.

I also heard monster difference on remastered cds.

But I don't hear anyor much difference so far between 128, 160, or 192 bit rates and I don't hear too much differences between mp3 or AAC.

I'm curious to hear what other ears have discovered. thanks!!

[TheBum]

I could tell a difference between 168 and 192 with headphones on. That's why all my MP3s are at 192. I also use the LAME encoder because the bass end seems rather muddy with the Fraunhoffer encoder (the one iTunes uses).

So far, I haven't been too impressed with the AAC tracks I've downloaded from iTMS. It seems rather weak on the bass end.

[zigzag]

You'll hear a lot of different opinions. Here's a test I like to refer to - it shows that in a double-blind test, music pros couldn't distinguish between original CDs and 256 MP3s, and had to listen carefully to distinguish 128 MP3s. Since AAC is better than MP3 at a given rate, I figure that 128 AAC is plenty good for non-critical listening.

[kevs]

Thanks I've never heard of Lame encoder.

Zig Zag, very interesting. Yes, I honestly could not hear so far, difference between 128 and 192, but on another forum someone just said they hear much difference and with hip hop huge differences.

So that's why I need more feedback. I'm going burn a lot of stuff so now I may be leaning to 128 again.

Any more opinions welcomed!

[tracheopterix]

There were a ton of articles on this when the iTunes store opened and AAC got big. I read about tests where music pros couldn't distinguish the bit rate differences and ones where they could. I tried testing myself and did find that I could hear a difference (it was a blind test) but only with guitar, electronic music was impossible for me to differentiate. But anyway, I decided to rip all my stuff at AAC 160 and so have a few friends of mine. It sounds damn good to me, and I can spare the extra disk space. If you are really an audiophile you should keep it all as aiff but that's damn big. There is definately a qualitative diference from aiff to mp3/aac.

I would love to see a survey of what encoding/compression people in this forum use for their music.

(((z)))

[kevs]

thanks trach, I'm leaning to rippint at 160 or 192 mp3. Others, please pipe in you wish!

[zigzag]

Originally posted by kevs:
\Zig Zag, very interesting. Yes, I honestly could not hear so far, difference between 128 and 192, but on another forum someone just said they hear much difference and with hip hop huge differences.

kevs, I just realized that I forgot to provide the link I referred to. Sorry - here it is:

http://www.geocities.com/altbinaries...l/mp3test.html

[hadocon]

Just use 192. Are you worried about disk space or something? Drives are cheap man!

[bracken]

aac or ogg. mp3 is a joke.

[kevs]

Thanks zig zag. great article.
Yes, I'm thinking of going 192 mp3.

I probably would not notice any difference at 128, but from what the article says, there may be certain times where is could be noticable.

[hadocon]

Originally posted by kevs:
Thanks zig zag. great article.
Yes, I'm thinking of going 192 mp3.

I probably would not notice any difference at 128, but from what the article says, there may be certain times where is could be noticable.

I don't understand why we are wasting time on this subject. Drives are huge, just get started already!

Jeez...

[erw]

Originally posted by kevs:
've always heard big difference between cassette tape and cd.

lol

[shatten22]

Originally posted by bracken:
aac or ogg. mp3 is a joke.

why is mp3 a joke?

i've got a bit of time on my hands now, I was thinking of re-ripping all of my cds to aac...

Is it worth it?

Should I keep it at 192 or 160?

thanks,

geoff

[kevs]

Yes I have a 300 GB external drive. But the i ipods are still at best 40GBs hence you fit a lot more at 128. That's why this is a great thread.

[ericdano]

Originally posted by kevs:
thanks trach, I'm leaning to rippint at 160 or 192 mp3. Others, please pipe in you wish!

I have been ripping everything now at AAC 160. I don't really hear a difference most of the time, except for things like cymbals or something. And 160 AAC seems to be alright to me, and the space the files take is small too.

My problem right now is space. 120 gig hard drive has 8 gigs free :-( Almost everything is either AAC or 192 VBR Mp3......time to set up that old PC with a RAID 5 setup and a couple of 200 gig Hds ;-)

[KevinPrice]

I started at 160...then could hear SOME differences (vs. 192) on SOME passages of SOME music. For MOST music it's not going to make much difference. (I'd describe the difference I hear as 'depth'.)

Here are the issues for me:
(1) Now that I'm used to 192, 128 DEFINITELY lacks 'depth' and spatial quality. On the other hand, I suspect if you get used to 128, you may NOT notice the difference when hearing the same song later at 192.
(2) Unfortunately, the songs where you'll hear the GREATEST difference will be the well-recorded, well-engineered numbers...and those fairly rare tracks are exactly the ones you DON'T want to screw up by going to 128.

The other posters are right...storage is cheap. Might as well just get started.

[tracheopterix]

to all posters in this thread:

please indicate the type of encoding your using - mp3/aac/ogg or whatever

there is a big difference between mp3@192kbps and aac@192kbps

I'd also be interested in hearing thoughts on the encoder used, i read some people like quicktime better than iTunes for some stuff, also there is n2mp3 etc. can they match the functionalty and quality of iTunes?

(((z)))

[kevs]

Thanks Kevin, very insightful. I do have a feeling that I probably would not ever care if I went 128, but from your post and others, I'll probably go 192 to be safe. I just want to pick one and stick with it. Again, space is cheap, but the ipods space is limited, so that's why I'm asking.


I'll probably get going in a week or so.

Trach:
Are you sure AAC is that much different than MP3? Some people says it's not that much better. A couple have even said they prefer MP3 for certain things -- like bass etc.

[Ken Masters]

I am addicted to BASS.

So what encoding process and bit rate should I use?

Right now, on my comp I have everything at 128kb AAC,

It was once all at 320kb MP3.

I Once invested a lot of money buying 3 IBM DEATH-STARS and in the first 1.5 years, two have already died. (Lost the warranty).


DIE IBM.... DIE!!!

[gunnar]

I have a pretty detailed listening test with OGG, AAC, MP3/LAME here:

Codec comparison

The problem with the c't test is that people's tastes are entirely subjective. As it said, many people liked the 128kbps files more often than the CD. That's not because they were confused about quality. When you introduce psychoacoustical compression it can act like a traditional filter (like EQ or reverb) where music can actually sound more enjoyable.

However, the point of a compression format is not to make it different or more enjoyable, it's to make it the SAME as the original. In testing, if you don't know what the original sound is supposed to be, it's impossible to judge the quality of the codecs. Completely subjective.

[zigzag]

Originally posted by gunnar:
I have a pretty detailed listening test with OGG, AAC, MP3/LAME here:

Codec comparison

The problem with the c't test is that people's tastes are entirely subjective. As it said, many people liked the 128kbps files more often than the CD. That's not because they were confused about quality. When you introduce psychoacoustical compression it can act like a traditional filter (like EQ or reverb) where music can actually sound more enjoyable.

However, the point of a compression format is not to make it different or more enjoyable, it's to make it the SAME as the original. In testing, if you don't know what the original sound is supposed to be, it's impossible to judge the quality of the codecs. Completely subjective.

Respectfully, I think this misstates the importance of the c't test. That a few listeners preferred a few 128s to the CDs was incidental. The main point was that a roomful of music and audio professionals, using extremely high-resolution equipment and listening carefully under double-blind conditions, could not distinguish 256 MP3s from the original CDs, and found it relatively difficult to distinguish at lower rates. This leads me to believe that since AAC is even better than MP3, there's not much point to ripping at 192-256 except for critical listening on extremely high-resolution systems, which few people actually do. I rip at 128 and have no complaints.

"Subjectivity" is what happens when people make comparisons in non-blind conditions, because they're pre-disposed to prefer a certain codec and/or higher bit rates. They also want to prove how good their ears are, so they describe things that they probably couldn't hear in a blind test. That's why I place little importance on comparisons that aren't blind. It's also why I chuckle when people claim to hear "obvious" differences on their little desktop speakers.

But to each his own.

[kevs]

Read Gunnar's test. thanks!

Just curious what is NMP3, and is it offered in itunes? I suppose you need a whole other software for it?

i tunes does have a checkbox for VBR. What are pros and cons of it.

thanks!!

[mproud]

As far as mp3s go, 128 is horrible. I describe it as "tinny" and although some songs are decent, it really does not contain the detail of higher bitrates.

160 is almost as inferior when based to 192 kbps. 192 is fairly decent, but of course pales in comparison with AIFF (naturally). But 192 is much, MUCH better than 128 and 160, and I simply will not listen to ANYTHING less than 192.

AAC is Apple's encoder for music. It is much better in comparison to MP3 at the same rate, especially lower rates. At some point around 320, the difference is almost negligible.

I too am trying to decide what to encode to. I have fallen into the AIFF trap. I have decided to keep AIFF on my computer so I can continue to make CDs with only the best (allowing me to make clean copies) and I think I may end up doing 192 AAC.

We'll have to see after I've ordered my iPod.

[Thilo Ettelt]

I too am trying to decide what to encode to. I have fallen into the AIFF trap. I have decided to keep AIFF on my computer so I can continue to make CDs with only the best (allowing me to make clean copies) and I think I may end up doing 192 AAC.

We'll have to see after I've ordered my iPod. [/B]

AIFF is very promising, but in combination with an iPod it's probably not recommendable due to reduced battery time.


- Thilo

[kevs]

mproud:

So you are going AAC? Are there any downsides you see as far down the road, by having a collection in AAC?

Also, want to ask again,
what is NMP3, and is it offered in itunes? I suppose you need a whole other software for it? i tunes does have a checkbox for VBR. What are pros and cons of it.

[Ken Masters]

Originally posted by kevs:
mproud:

So you are going AAC? Are there any downsides you see as far down the road, by having a collection in AAC?

Also, want to ask again,
what is NMP3, and is it offered in itunes? I suppose you need a whole other software for it? i tunes does have a checkbox for VBR. What are pros and cons of it.

SLOW AS hell to encode!!!!

That is the only problem i have, it is at least 4 times longer to encode with AAC.

APPLE really has to do something about the encoding process.

[kevs]

Ken :
I've only ripped a couple of song with AAC and did not notice any slower importation. But if what you say is true, there is always a new twist to this story.

Did you notice any sound improvement with AAC?

What about second part of my question about
NMP3 and VBR?
thanks!

[HerbVic]

Anyone who has ever tried to use a cheap wireless phone has heard the extreme effects of digital compression. That is the type of distortion to be looking for when comparing mp3 or AAC with AIFF. That and artifacts.

At 128 or above you likely can't hear the compression distortion, but on comparing music to its original it may not sound as full. However, it takes almost ideal conditions to make it discernable. Every sound mixes with every other sound in a room and is also affected by the size room and texture of the walls. You have to have a really good sound system and an excellent room, and even then you have to be trying to hear the difference.

The artifact distortion is a different matter. The same compression algorithm can perform perfectly for a long time before it meets the right set of ingredients in the source material to cause an artifact. If you are very familiar with the music, the artifact will stand out like a sore thumb. IMHO, over processing of the source material can lead to an artifact in compressing to mp3. Other than that, I have no idea what causes it. But, it can happen even at higher bit rates, and on discovering an artifact, re-ripping at a higher bit rate did nothing to eliminate it.

In my experience of ripping CDs to mp3, I discovered that re-ripping the same tune [that produced artifacts in iTunes] in SoundJamMP would not create the artifact. After that, I fell back on SoundJamMP for ripping for awhile. Later, I reverted back to iTunes and haven't noticed any more problems.

I currently have over 2800 tracks in mp3 & AAC collection. Most are ripped from CD to mp3. About 50 were bought from iTMS. Some mp3s were legally downloaded from eMusic.com. eMusic used 128 bit mp3. For some reason their 128 bit sounded fuller and better than the 128 bit generated by iTunes (probably because they were using digitally remastered and I was using AIFF CDs as source material), so I gave up on 128 bit and started using VBR with a 128 bit floor.

Variable Bit Rate (VBR) just lets the software select the optimum bit rate after analyzing the tune. You bias the process by selecting from a quality list.

My suggestion would be to choose high quality VBR with a 128 bit floor and don't let the compressor throw away frequencies below the audible range since the harmonics of the low freqs will interact in the audible freqs range.

About AAC: I think they sound pretty good, but seem to be digitally audible at lowered volumes. In other words, it seemed as though I could barely detect the digital distortion when listening at much lowered volumes, whereas at higher volumes it sounded great.

HerbVic

[kevs]

thanks Herb.
this morining tested 3 songs of kind of music I listen to, rock, Lennon, Neil Young, McCartney at 128 128 AAC and 192. I could not hear any differences. This was on good stereo -- not super high end. Have not tested on an i pod yet.

[cmlewan]

You guys should read http://www.ovolab.com/aachoo/aboutaac/ : "According to Apple, expert listeners have judged AAC audio files compressed at 128 kbps (stereo) to be virtually indistinguishable from the original uncompressed audio source, whereas MP3 files at the same bitrate (taking up the same amount of space on your disk) contain audible artifacts."

And: "On a subjective scale ranging from 1 (low quality, bad artifacts) to 5 (excellent quality), AAC audio at 96 kbps resulted in a better and cleaner sound (score 4.4) than MP3 at 128 kbps (score 4.1)."

And please, don't even bother making home-made tests if they aren't blind-tests.

I think I'll go for 128 AAC. Most reported differences to AIFF, when it comes to compressed formats, are delusions.

[kevs]

I find there is no difference between AAC and MP3 regardless of what the tests say. This is with music on ipod or in car. In home stereo I find all compressed music sounds way inferior to uncompressed.

[cmlewan]

One more thing: Apple itself uses only 128 AAC (on iTMS) so they have taken the decision that it's good enough for every reasonable purpose.

Also, in one of the reports off the page I gave you the link to, AAC got the note 4.8 where 5.0 was the highest. No other format came really close, not even 192 MP3.

I'll use 128 AAC for my record collection. Then I'll sell the records.

[shatten22]

Originally posted by cmlewan:
One more thing: Apple itself uses only 128 AAC (on iTMS) so they have taken the decision that it's good enough for every reasonable purpose.

Also, in one of the reports off the page I gave you the link to, AAC got the note 4.8 where 5.0 was the highest. No other format came really close, not even 192 MP3.

I'll use 128 AAC for my record collection. Then I'll sell the records.

For my money, 192 AAC sounds better than 128 AAC. And I've stopped buying music off of ITMS. Not being able to re-download stuff already purchased is insane.

-g

[spiky_dog]

Originally posted by shatten22:
For my money, 192 AAC sounds better than 128 AAC. And I've stopped buying music off of ITMS. Not being able to re-download stuff already purchased is insane.

-g

i agree in full. i downloaded one album, wiped my music directory clean by mistake and then looked around in vain for a redownload option. silly me