Treat a resonance as a family, not a spike — the case for branching

The stock move on a boxy guitar is a narrow cut around 300–500 Hz. Sometimes it works. Often the boxiness steps sideways: you killed 400 Hz and 800 Hz starts conducting the same cabinet. That is not the universe being rude. That is a resonant family. Cabinets, toms, and simple synth patches ring at related partials. A single notch is a single vote.

Branching, in the actual plugin

You plant a root on the obvious offender. You grow a grid. If the octave or the third is also guilty, you cut those grid bands too. If one of those related tones is not merely a cousin but a second problem with its own spread — a tom’s pitch plus the overtone that turns into stick noise — you promote that grid band to a new root. The new root can use a different prime and a different Q. The parent remains. The UI draws a tree because the DSP is a tree of ownership, not because it looks like a forest app.

Limits, again, because they matter in this use: eight roots. Promoting does not give you infinite depth. It gives you a second (or third) center of gravity. Past that, you are probably looking at a different problem — a room mode, a bad take, a distortion plugin generating inharmonic fuzz that a harmonic grid will only approximate.

A tom example without folklore

A rack tom’s pitch might sit near 180 Hz. The “ring that survives the gate” is often an overtone, not the fundamental. Plant 180. Grow octaves. Listen to 360 and 720. If the ring is a non-octave partial, switch prime to 3 and see whether 540 Hz is the culprit. Cut the guilty node a few dB with a higher Q than you would use for tone. Leave the fundamental if the tom still needs body. That sequence is testable. A cheat sheet that says “toms at 200 Hz” is not.

If you cannot tell whether the ring is harmonic, it might not be. Metal hardware, sympathetic snare, and headphone bleed will not sit politely on a prime grid. In that case the honest tool is a parametric notch or a gate, and RootEQ should stay out of the way.