Input impedance (modulus and argument) and reflection coefficient (modulus and argument) of an acoustically regular conical resonator (solid black lines) with a first impedance peak at 177 Hz and a theoretical global tonehole lattice cutoff frequency at 750 Hz. A conical resonator (dotted lines) with the same first impedance peak frequency but no tonehole lattice is shown for comparison. The first three impedance modulus peaks are marked by a solid black line (resonator with a lattice) and dotted lines (simple cone). The cutoff transition band (defined in Sect. 2.4, Eq. (19)) is shown in shaded grey.