Each and every audio track on either a cd or cdr, is multiple of 2352 bytes in lenght.
It cannot be any other way, this is due to the redbook standard.
We could also put it this way: the building blocks of an audio cd track are 2352 bytes long.
Those building blocks are also called sectors.
(2352 bytes = 588 samples = 1/75 second = 1 sector)

When you edit, cut, manipulate a wav in any way in an audio editor, the resulting .wav will most
likely not be multiple of 588 samples (= 2352 bytes).
Due to the sample-accurate nature of most audio editors you can cut a wav anywhere you want.*
Audio-processing will also affect the data, meaning that the lenght of the wav will most likely
be changed as well.
When burning this kind of "home-made" wavs to audio cdr, every burning app, in order to comply with the
redbook standard, will either chop off the end of the wav or pad it with silence until it has a lenght multiple of 588 samples. **
This kind of alteration performed by the burning app to the .wavs we've created in an audio editor,
will introduce clicks between tracks.

In order to avoid those annoying clicks, we need to fix these .wav files before they get burned.
Remember, 2352 bytes = 588 samples = 1 sector, so when we have .wav files that are not multiple of 2352 bytes in lenght, we say that they have sector boundary errors.

In order to fix those sector boundary errors, shntool will perform a small byte shifting between
adjacent wav files so that each wav in a set has a lenght multiple of 2352 bytes (588 samples).

In fact, the byte shifting is extremely small, less than 588 samples = less than 1/75 second.
And this is only byte shifting, audio data remains intact of course, no audio data is chopped off,
no silence is added between tracks.
Only the end of the very last track in a set containing sector boundary errors will be padded with
a few bytes of silence in order to make it a mutiple of 2352 bytes as well.
When burning these fixed files we will have cd tracks that go right into the next one seamlessly
just like we heard it in the audio editor. No clicks.

With shntool we will scan lossless files for possible sector boundary errors,
and we'll be able to fix them so we can avoid clicks when burning to audio cdr.

shntool is a small command line utility. It has no graphical user interface.
Since command line is so unfriendly, the best option is to use batch files and associate them
with the .ape, .flac, .shn, .wav extensions.

We will then be able to use shntool very easily straight from the right click menu of any
.ape, .flac, .shn, .wav file :)

* Even if with some audio-editors you can cut a .wav at sector markers, it is always good practice
to check for sector boundary errors with shntool.

** Feurio is the only burning program that detects and fixes sector boundary errors before burning.

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