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EAC Ripping In Depth

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VERY BIG DISCLAIMER: EAC is a powerful tool with hundreds of options. No two people will have exactly the same setup or preferences. These preferences produce accurate rips with undamaged and damaged discs, and even if a track has an error, it is usually inaudible. This arrangement strikes a balance between speed and accuracy, leaning more towards accuracy, so don't expect fast rips on damaged discs.


Set Up EAC

There are lots of guides out there. A good one is the Quick Guide here. The guide is fairly current except for the LAME MP3 encoder settings. See here for the current recommended settings.

Best MP3 Guide: Here is a step by step guide to setup EAC and how to rip in mp3 in the best possible quality (you can download tools & settings from there too).

Also install AccurateRip, which will give you a clear indication if others are getting the same audio data as you, down to the last bit.

ANOTHER VERY BIG DISCLAIMER: The "Drive caches audio data" option is controversial. Some on HydrogenAudio take this to mean that the drive caches audio data - therefore EAC should overwrite the cache on each read so that it's reading data directly off the disc and can compare sectors to find errors. Others take this to mean "use the drive cache", which would defeat the whole purpose of error correction - EAC would read the data in the cache, not the disc, and the data in the cache would be the same every time. Enabling this option for drives that have this feature autodetected or from the EAC drive database works for some, but the consequences of getting this option wrong completely negate the whole EAC concept, hence this disclaimer. You may wish to conduct some experiments with the option checked and unchecked on known bad tracks.


What EAC Does

Most of this is covered in the quick start guide. Generally, EAC will extract the CD tracks to WAV files, then call an external encoder to encode the files. The external encoder is often a command-line encoder, therefore you will see a DOS window pop up, although you can disable this. When the encoder is finished, the WAV is deleted - you can also disable this but there's no need to if you're encoding to a lossless format.

The ripping and encoding processes are entirely separate. Therefore EAC can still be ripping while the encoder is working, or EAC can have finished ripping the disc while the encoder is still running. In fact, if you have set EAC to automatically eject the disc after ripping, you can load another disc while the encoder is still running. Note that you can set EAC to rip everything, then start the encoder, or start multiple encoder instances. Since EAC doesn't significantly load the processor, you can safely run at least one compressor instance while EAC is ripping. Running more than one compressor instance heavily loads the processor and is not recommended, but you can do this, see EAC - EAC Options - Tools - "On extraction, start external compressors queued in the background", followed by the number of external conmpressor instances allowed.

While the encoder is still running, the filenames and files in the directory where the encoded files are being written will not be accurate. There may be temporary WAV and compressed files with bizarre names. Do not delete them or attempt to load them. They are incomplete and loading them may interrupt the compression process.


Procedure

  1. Examine the disc. Look for fingerprints, dust, dirt and scratches. If you find any, clean the disc with a glass cleaner. Always wipe in a straight line from the centre of the disc to the edge, never in a circle along the circumference of the disc. If the disc is clean but scratched, a cleaning will assist your drive in reading the data correctly. If the disc is clean and undamaged, it is not recommended to clean it as cleaning may cause slight wear and scratches on the disc.
  2. Load the disc. You may wish to open EAC and only load the disc with EAC running. When EAC is running, it defeats autorun, ensuring that any computer program on the CD is not automatically loaded onto your PC. You should also disable autorun in Windows for the drive, but this is a double assurance.
  3. Correct any freedb inconsistencies or errors in the album and track names. Press F2 to edit track names. This is important as all tags will be based on this data. It's much simpler and quicker to change it now. If an error gets by at this stage, you will have to change not only the tags but the file names of the compressed files. This becomes especially time-consuming when you rip to multiple formats using MAREO.
  4. You may wish to detect gaps by pressing F4. See here for more info.
  5. Rip the disc using EAC's "MP3" button. Don't worry, this won't rip to MP3, it will rip to any encoder you've specified in EAC's Compression Options. You should probably rip to FLAC if you're using a Squeezebox, but you may wish to rip to MP3 for portable devices.
  6. When extraction to WAV is finished (compression may still be running), check EAC's extraction results window. The quick guide suggests writing a log automatically, but you can disable this option and only write a log if there were errors. The logfile will indicate which tracks have errors and where the errors are located. You can also tell EAC to skip the track if it encounters errors, which will draw further attention to those tracks. If there were no errors, move on to the next disc.
  7. If there were errors, listen to the tracks at the error positions noted by the EAC logfile. Use headphones so you can very precisely listen to the track for ticks, clicks, pops or dropouts. 95% of the time you will probably not notice any errors. 4% of the time you may hear a slight tick in one channel. 1% of the time you may experience a dropout.
  8. If there were no audible errors, move on to the next disc. If there were audible errors or if you're determined to get an accurate rip no matter how long it takes, you may wish to use a CD repair kit. But first, hold the disc up to a light. If you can see light through scratches and specs in the aluminum layer, you cannot repair those sections. Re-rip those tracks in WAV and use EAC's glitch and pop removal tools. If the aluminum layer is intact, the glitches are caused by scratches. You will probably be able to guess which scratches are causing the errors. A CD is read from the centre to the edge, so from this you can guess where each track is located, and a defect causing an audible error will almost always be visible. On many older discs, you can see the data itself, visible as a dull area - it may not go right to the edge.
  9. Re-rip the repaired tracks. 95% of the time the track will re-rip without errors. 5% of the time the errors will be reduced. It's very rare to have an audible artifact remain, but if it does, re-rip the track in WAV and use EAC's glitch and pop removal tools.