Does a higher synthesized pitch mean the actual black hole produces a higher note?
Here, pitch comes from an authored six-point profile and your selected mapping curve. No telescope file, measured pressure waveform or NASA audio is loaded. Use the presets to compare how encoding choices alter sound, then follow the original NASA and Chandra examples for data-based sonification.
The kiloparsec distances, flux values and density-like numbers are unsourced fixtures. Neither the first point nor the scrubber endpoint is an event horizon. Live playback adds oscillator layers and compression; WAV export contains only a three-second sine at the current fundamental, without those effects or a radial sweep.
Choose the M87-inspired profile, scrub to its end and select Linear at the baseline shift. The authored value is 0.03, so pitch = 40 + 0.03 × (8800 − 40) = 302.8 Hz. Move the shift slider one step from 57 to 58: the relative shift is +1 octave, so the pitch doubles to 605.6 Hz. These are mapping results, not measured astronomical frequencies.
The scrubber interpolates equally between array indices, not uniformly between the uneven distance values. Linear uses d; logarithmic uses log10(1 + 9d); exponential uses d². The resulting pitch is multiplied by 2^(slider − 57) and clipped to 20–20,000 Hz. The old transposition display used an unrelated exponent; it now shows the actual pre-clipping multiplier.
Live sound uses one sine oscillator and up to four additional oscillator layers at integer multiples of the fundamental. Even layers use triangle waves, so the layer count is not the number of individual spectral harmonics. Compression changes the live threshold; the flux fixture does not control audio volume. CSV exports 21 interpolated positions using current pitch settings. The FFT visualizes generated audio, not an astronomical spectrum.
NASA’s Perseus project extracts pressure-wave information in cluster gas and raises it by 57–58 octaves for hearing. That is distinct from representing light observations as sound; sonification is not always an acoustic recording. NASA: black-hole sonifications with a remix
Chandra’s M87 description uses X-ray, optical and radio observations on wider scales. It explicitly says that particular sonification does not use EHT data. Neither source validates this page’s fixture arrays. Chandra: original sonification media and explanation
Distinguishes Perseus pressure waves from M87 sonification and explains the large octave shift.
M87 multiwavelength mapping and explicit exclusion of EHT data from that project.