Bach_guitar.rar -

Looking for a in the archive (using 7z l -slt Bach_Guitar.rar ).

Use strings to look for readable text at the end of the file. Inspect the LSB (Least Significant Bit) using zsteg . Open the file in Audacity . Bach_Guitar.rar

Data hidden after the "End of File" marker (EOF), viewable in a Hex editor. Looking for a in the archive (using 7z l -slt Bach_Guitar

Attempt to extract the archive. Many versions of this challenge are password-protected. Bach_Guitar.rar

Text appearing as "waves" in the audio spectrum.