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swstereo
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Using "error correction" in iTunes - yes or no for best fidelity?

In JA's article

http://www.stereophile.com/mediaservers/1008servers/index.html

he states: "We recommend that, for serious listening, audiophiles use uncompressed audio file formats such as WAV or AIF"

There is no mention of using error correction or not - will this affect the overall quality of the sound?

In doing numerous online searches, answers to this question involve clicks, pops, speed and usefulness but not the overall fidelity that may or may not be affected by using error correction.

Under iTunes preferences, there is a box to be checked if one wants to use "error correction". Before I copy 500 or so CDs for my new Transporter, a definitive answer would be very helpful.

Thank you.

EDIT: I am using iTunes 8 on an Intel iMac Leopard 10.5.6 and will switch to iTunes 9 in a few days. I am importing everything in AIFF as it is native to Transporter - no decoding needed.

Sorry that I left out this information when originally posting.

jazzfan
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Re: Using "error correction" in iTunes - yes or no for best fide

I'm pretty sure (something like 99.9% but not quite 100%) that the error correction used in the average CD player is not the same as the error correction used with computer data. That said when using a music server one is not using CD error correction but computer data error correction, which is a horse of a different color. Hopefully someone else with slightly more computer savoy can elaborate on this issue.

When one rips a CD onto a hard drive one creates a data file of the musical information and that data file is then treated the same as all other computer data. As long as the hard drive itself does not become corrupt or faulty the data remains error free otherwise the file could not be 'played". Just make sure that rip your CDs using a program that can verify that the data file created on your hard drive is identical to the data on the CD. Two such programs are Exact Audio Copy (free) and dbPowerAmp ($ but well worth every penny of the modest asking price). Note: these programs are Windows based, I do not know which Mac programs provide for accurate CD rips.

ncdrawl
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Re: Using "error correction" in iTunes - yes or no for best fide

if you want a solution that maintains file integrity, use
Exact Audio Copy. Bit-perfect reads every time.

http://www.exactaudiocopy.de/

http://www.exactaudiocopy.de/en/index.php/overview/basic-technology/extraction-technology/

it also has FLAC built in as one of the codecs..

dcstep
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Re: Using "error correction" in iTunes - yes or no for best fide

If you use Apple Lossless, then, by all means, use error correction. I use Lossless because of my stupid iPod and iPhone and don't want to do multiple rips. However, for a HD there are probably better choices.

Still, when I use Lossless with error correction with the iPod's output through a Wadia 170i, into my upsampling to DSD Playback Designs MPS-5's digital input and compare that output to the PD's direct output, they cannot be distinguished. OTOH, if I don't use error correction, then some of the files sound noticeably different and inferior.

The files are all playable, but the error correction seems to make them pretty near flawless. Much as I hate Apple and its restrictions on the movement of files that I own, it does actually work well. However, I'd only recommend Apple to someone using Apple hardware.

Dave

Editor
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Re: Using "error correction" in iTunes - yes or no for best fide


Quote:
In JA's article

http://www.stereophile.com/mediaservers/1008servers/index.html

he states: "We recommend that, for serious listening, audiophiles use uncompressed audio file formats such as WAV or AIF"

There is no mention of using error correction or not - will this affect the overall quality of the sound?

Yes, use error correction if you are ripping with your Mac, otherwise use Exact Audio Copy as someone else recommended. You want the bits in the file to be identical to those on the CD.

John Atkinson
Editor, Stereophile

swstereo
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Re: Using "error correction" in iTunes - yes or no for best fide

Thank you Mr. Atkinson and everyone else who took the time to respond. It is appreciated!

struts
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Re: Using "error correction" in iTunes - yes or no for best fide

Hey sfstereo,

There are no programs I am aware of for the Mac that properly implement an ability to set individual drive offsets (required for completely accurate rips) but there are at least two that do correct most types of read errors, xACT and Max.

These may produce better quality rips than iTunes although unfortunately we just don't know as afaik Apple has never published the spec for iTunes's "Use error correction when reading Audio CDs". It is probably doing something similar to the above two (in which case the original answer to your original question is "yes"), we just don't know exactly what.

If you are intending to use your Transporter wirelessly I would strongly recommend using FLAC which will save you disk space and network bandwidth (less stress on your router = fewer glitches and dropouts). This will mean you can't use iTunes for ripping or library management but luckily there are plenty of alternatives. You can find a list of FLAC rippers for Mac OS here. Good luck!

ROLO46
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Re: Using "error correction" in iTunes - yes or no for best fide

Apple Lossless with error correction
Renew Disc Permissions in disc utility every time Tunes upgrades.
Its simple...

audioengr
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Re: Using "error correction" in iTunes - yes or no for best fide

Definitely use error correction turned-on.

Also, be aware that iTunes ALAC ripper may have had some strangeness prior to release of version 8.

I had a number of customers and even reviewers report that .wav files ripped using EAC on a PC and then converted to ALAC with iTunes on a Mac sounded better than CDs ripped directly to ALAC with the older versions of iTunes.

If you have ripped a lot of tracks with older versions of iTunes, I recommend you do this experiment yourself to determine if it is an issue for you and your system. I recommend to download version 8 iTunes and rip with this (error correction enabled)going forward.

A number of my friends (as well as Gordon Rankin) are performing experiments to determine what is going on here. Nothing to report yet as to the cause.

Rips with the older iTunes and the version 8 have perfect data compares BTW, so data compares dont tell us anything about this anomaly.

Steve N.

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