The background structure is a photo (moiree effects in a microphone filter, JPEG), the left bar is made with a design program (Affinity Designer, PDF) and doesn’t include the structure, everything put together using [[Transparency]].
The image above is not a photo of the printed cover but just a JPEG export of the PDF; i.e. even if the cover paper is new and smooth, it looks structured and a bit faded.
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