Flut-O-Mat PVC & 3D Print Edition

Acoustic Tone Hole Calculator with Non-Linear Shift Corrections

Specifically made for Blue Bear Tone Box and 3/4 inch schedule 40 PVC pipe

1. Fundamental Key & Scale

2. Pipe & 3D Fipple Dimensions

in
in
2.345 in

Default calibrated for standard 3D-printed fipples on 3/4" PVC ($\approx 2.35\text{"}$). Adjust if your headjoint window is wider or narrower.

3. Tone Hole Diameters

Change hole sizes to adjust finger spacing! Larger holes shift downward, smaller holes shift upward.

Visual Pipe Scale Diagram

Total Cut Length: --
Speed of Sound --
Bell End Correction --
Max Finger Reach --

Hand Stretch & Playability Analysis

Complete Drill Cut List

All measurements measured from the center of the Fipple Window

Hole Note Hole Size Dist. from Fipple Inter-Hole Gap Downstream Shift

The Math Under The Hood

This calculator solves the full open-pipe wave equation: L_physical = (c / 2f) - ΔL_fipple - δ_hole - δ_downstream.

As you move up the pipe toward higher pitches, the enclosed mass of dead air below the open hole creates an added inductance (δ_downstream) that forces the hole position higher than traditional linear calculators predict.