Considerable Improvement with EAC Rips

To answer all of the above:

I certainly do not use lossy compression. That would be a violation of every audiophile instinct (neuroses) in my body! I use uncompressed .aiff, which as a side note, I believe is identical to .wav in sound quality. I use it because .aiff seems to handle meta data tags better and if the iTunes library every gets corrupted or lost, the files themselves will retain some artist and album information.

The operating system is Windows Vista. In this case, it makes a difference because I am not aware of a program like EAC on the mac. You could do this with XP. Plextools might give similar results on Mac but I'm not sure about that. I don't have a mac.

The process for me is the CD drive straight to an internal hard drive that is separate from my main system disc. The library is managed by iTunes. The Squeezebox III serves the files to the DSC from wifi and provides the interface. My computer (intel quad core) serves as only ripper and file server.

The process to integrate EAC with iTunes is as follows:

1. Download and Install EAC

http://www.digital-world.de/downloads/audio/exact_audio_copy_v_095_beta_4_international/1253089/exact_audio_copy_v_095_beta_4_international.html

2. Download and Install iTunesEncode in the EAC folder

a.download at: http://www.hydrogenaudio.org/forums/index.php?s=41a94476ff9f5e9a25eea39e5c88c32d&act=Attach&type=post&id=1617

b. Extract iTunesEncode.exe into the same folder as EAC, usually it is (C:\Program Files\Exact Audio Copy). Just copy it into the folder, there is no installer program for ItunesEncode.

iTunes Encode is a command line program that needs to be fed a command string to tell it what to do. EAC will feed it that string but you have to set it up.

3. Configure EAC to use iTunesEncode
a. launch EAC (you may have to go through EAC configuration wizard if you haven't yet.)
b. in EAC, go to the following menu: EAC-->Compression Options-->external compression.

c. In external compression, set the following options:
(i). check "use external compression"

(ii). parameter passing scheme: set to "user defined encoder"

(iii). press "browse" and find and select the iTunes encode program, which should be in your EAC folder at this point.

(iv). Make the file extension option the extension of the itunes compatible format you wish to use (.aiff, .alac) but note that changing this only marks the files with the exension, IT DOES NOT ACTUALLY CHANGE THE FORMAT. That part comes next.

(v). Most importantly, enter the following command string into "additional command line options":

-e "AIFF Encoder" -a "%a" -l "%g" -t "%t" -g "%m" -y %y -n %n -i %s -o %d

Just copy and past it in exactly as it is seen above. If you want to use an encoder other than AIFF, change "AIFF Encoder" to to a different encoder. Within those quotes you can name whatever iTunes encoder you want to use and THAT is what will tell iTunes to use the appropriate encoder.

You may choose from "AAC Encoder", "WAV Encoder",
"MP3 Encoder", "AIFF Encoder",
or "Lossless Encoder".
(Default is "AAC Encoder".)

Some of this information is included in the readme file for iTunes encode.

(vi) I don't think the bit rate pull down does anything in this context but just to be safe make it the highest value which is 1024. It don't think it is really a factor though.

Click OK. Now EAC should be configured to encode into itunes. EAC will rip the files and after each file rip, iTunes encode should automatically launch itunes and use it to encode and important the files.

Note that EAC is capable of either retaining the original wav or deleting it. I personally have it delete the original wav automatically.

There is one other nuance here. The way I have my iTunes setup, everything it imports gets neatly COPIED and placed into a series of folders organized by artist and album. iTunes does this automatically for me and probably for you to. Thus after ripping, you may have a copy of the encoded file in your EAC folder, or whatever folder EAC is set to output to, AND in your iTunes music folder. This is a product of iTunes making a copy and keeping your itunes music folder organized. What I do is clear out my EAC folder the same way I would periodically empty the trash bin otherwise the duplicates build up. I also make sure EAC is set to delete the original .wav it creates before encoding or I would actually have three lossless copies on my drive after each rip.

Hope that helps.

DTC I'm not sure how I would go about looking bit by bit.

Also, sorry I meant to say the The Squeezebox III serves the files to the DAC, not DSC. Typo.

I should also mention that when you configure EAC as I described above, you want to use the mp3 button or "compressed" option to trigger your rips because that is what tells EAC to use the external encoder. If you clicked uncompressed, EAC would simply make a wav without using the encoder.

Also make sure you go to drive options and detect and select the drive that does not cache, has c2 error correction and accurate stream. EAC will tell you what functionality your drive has.

Drubin, first, I DID say what the "right" drive is. It is a drive that 1) does not cache audio, 2) uses c2 error correction and 3) uses "accurate stream". Mine happens to be a SAMSUNG 20X DVD±R DVD Burner Black SATA Model SH-S203B. Those three features are not present in all drives and EAC test your drive and tell you what features it has. Whether it caches audio seems to be luck of the draw. If your drive caches audio, EAC has a means of defeating it.

Second, it is true that the Goldmund did not do any re-reading. It was also a $6k "mechanically grounded" stand alone single disc device that was designed to get it right the first time. It was a CD turntable that weighed a ton and had a clamp that sat on the CD. It also read in real time at 1x speed. My internal DVD-ROM with EAC seems to do the same job for $30. It speeds up and it slows down. That doesn't bode well for transports.

I have not tried this myself, but it has also been said in various forums that if you compare checksum values for different rips of the same track, it is not uncommon to get different values each time--the file is different. The error correction is supposed to mitigate this. EAC actually compares your rip with a database of rip checksums and will tell you how accurate it thinks your rip is. It usually falls within 98%-100%.

I am not trying to convince you that it sounds better, I am only adding my personal experience with these forums. I don't have enough technical knowledge to make an actual argument for EAC based on theory. My hope was that more people would try it and report back.

Dtc, thanks so much for your input here.

Here is the problem. I did the EAC comparison on the tracks below but I got the same sort of results you did. It did not really turn up anything suspicious and this was true comparing EAC paranoid mode tracks to both Itunes error corrected and uncorrected tracks. It pretty much turned up six samples at the beginning as the only difference, but +6 is also the amount of samples that EAC is set to offset on my drive.

I don't think EAC compare does a thorough binary comparison, however. I think its primary function is to determine the drive offset--which I don't think is critical to sound quality. I could be wrong.

BUT, foobar I know does a bit/binary comparison and this is what turned up when I compared the same tracks that EAC said were the same:

Comparing:
"C:\Users \Desktop\EAC TEST\The Driving Of The Year Nail.wav"
"C:\Users \Desktop\EAC TEST\iTunes\Leo Kottke\6- And 12-String Guitar\01 The Driving Of The Year Nail.wav"
Differences found: 10,048,036 sample(s), starting at 0.1579819 second(s), peak: 0.9287415 at 93.9665079 second(s), 1ch

Note: If I read this correctly, it picked up a difference at .15 seconds with a "peak" at 93.9 seconds

Comparing:
"C:\Users\Desktop\EAC TEST\iTunes\Leo Kottke\6- And 12-String Guitar\02 The Last Of The Arkansas Greyhoun.wav"
"C:\Users \Desktop\EAC TEST\The Last of The Arkansas Greyhounds.wav"
Differences found: 17,147,577 sample(s), starting at 0.1472336 second(s), peak: 0.8823242 at 84.7079592 second(s), 1ch

Comparing:
"C:\Users\Desktop\EAC TEST\iTunes\Neil Young\Live Rust\05 My My, Hey Hey (Out Of The Blue 1.wav"
"C:\Users\Desktop\EAC TEST\My My, Hey Hey (Out of the Blue).wav"
Differences found: 22,194,539 sample(s), starting at 0.0000000 second(s), peak: 0.8122864 at 0.7691383 second(s), 2ch

Comparing:
"C:\Users\Desktop\EAC TEST\iTunes\Sting\Soul Cages\02 All This Time.wav"
"C:\Users \Desktop\EAC TEST\All This Time.wav"
Differences found: 25,913,572 sample(s), starting at 0.0000000 second(s), peak: 1.5827637 at 117.6406349 second(s), 1ch

I am not sure what conclusions to draw from this result but I suspect the differences I am hearing are attributable to the millions of samples that are different? Could this data be right? Could it be millions of samples? These discs were all in good to excellent condition. All of the iTunes tracks were error corrected.

No problem. Aiff is a bit more obscure than .wav but basically they are identical. Aiff is an apple standard but unlike apple lossless, aiff is almost universally supported. I use it because aiff has better metadata tagging functionality.

Here is the thing. When I rip the same track twice using iTunes w/ error correction and then use Foobar to compare the two .wavs, it typically finds NO differences. In one case it found a difference of 24 samples which obviously is negligable. The same is true with two consecutive rips using EAC. So it is not as if iTunes is not capable of producing consistent results. It just produces results consistently different from EAC--if Foobar is to be believed.

Whether those difference are material to sound quality I don't know--but Foobar at least gives some support to the idea that the files are different IN SOME WAY.

Dtc, I think your hunch about the EAC's offset correction (in my case it was set to +6) throwing Foobar off was correct. If you go into the EAC folder and temporarily disable the Accurate Rip function by changing the filename of acurraterip.dll to acurraterip.dll.whatever, you will find when you fire up EAC that you can now adjust your read offset and that it is set to +0 by default.

When I used Foobar to compare an EAC rip with +0 offset to one with +6 I found that it reports the millions of samples that we have been encountering. Further when I Foobar compare the +0 offset EAC .wav to an iTunes .wav, Foobar reports NO DIFFERENCES!

So I think at this point both EAC and Foobar are telling us that there is no difference between the EAC rips and the iTunes rips--at least on the track I tested.

At this point I have to acknowledge that there may be have been a powerful placebo effect at work in my listening tests. I can't say I believe any longer that EAC is better under all circumstances. On the disc I tested today I could not detect any difference in sound quality between the two. I was able to play it a bit louder today because I had the house to myself. That disc was in pretty good condition.

I will continue to use EAC because I like the way it behaves and the feedback it provides, but I am not sure what if any value it adds with respect to sound quality.

Yes, exactly. It has to do with alignment of the drive head. There is absolutely nothing I have found that suggests this has anything to do with sound quality. The "correct" value for offset depends on your drive.

I'm not really sure what it does or what value it adds but it does not change the bits of the music. It just moves them enough that Foobar can't match them anymore.