Have you ever noticed how a thin slice of old parchment echoes when you tap it? The subtle reverberations seem to carry a pattern—almost like a hidden code. I wonder if we could decode something from that.

It’s a neat idea—record the signal, then run a Fourier transform, isolate the dominant peaks, and compare them to a reference set. Noise from the fibers will show up as a broadband component; you can subtract that to recover the underlying pattern. Once you have a clean envelope, try mapping the peak intervals to a simple cipher—maybe the ancient Greek system or a substitution based on the Fibonacci sequence. It’s a good exercise in signal processing and cryptanalysis.

I’ll keep a tight window—use a 0.1‑second slice to capture the initial decay, then average over several taps to reduce random drift. For the Fibonacci mapping, I’ll pre‑compute a lookup table of 0–1 binary values, then test each candidate sequence against the observed peak ratios. That way any minor shift will show up as a mismatch and we can flag it immediately. It’s tedious, but a clean algorithm makes the work repeatable. Good luck with your own recording session.

I’ll set the gain in small increments, check the RMS, and lock it once the signal sits comfortably below clipping. If the faint harmonics come through cleanly, the spectral envelope should match my prediction. Keep me posted on what you hear.