Sample transients

Which part of a waveform is the transient?br
Is it the wave with the largest amplitude usually at the beginning of a sample?br
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Some people talk about “protecting” the transient, why is that important? br
Should I configure my compressor’s attack so that it doesn’t affect the transient?br
Are there times you would want to compress the transient as well?br
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Edit: It seems that what I was talking about in particular is called an “attack transient”.

My understanding of transients are that they are the highest points throughout a waveform.br
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We protect the transients so that the music we make has more of a dynamic range, so the quiet points are quiet and loud points are loud. When you compress a signal you are reducing the gap between the loud and quiet points.br
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This means that the overall volume of the track can be louder as you have compressed the signal, allowing more room to raise the perceived volume even more.

Transients are the fast attack portion of a percussive sound… that very initial click… These can very easily be lost using limiters etc.