Acoustic calculator: Room modes

Simplified analysis of axial room modes

Enter room dimensions.
The program will automaticly calculate resonanses and detect isolated and degenerate modes.
Use the dot as a separating char.
Room measurements

Air temperature °C
Reverberation time sec
Speed of sound 344m/s
Room volume 45.5m3
Critical distance 0.9m
Room proportions (H:L:W)

Frequency regions
Lower boundary of audible range F1 16Hz
Boundary of sound pressure zone F2 34Hz
Schroeder's frequency F3 210Hz
Boundary of reflection zone F4 840Hz
Upper boundary of audible range F5 20000Hz
1. If several axial modes coincide (spacings between modal frequencies are equal to zero), they are called degenerate modes. This often causes a distinct peak in the amplitude-frequency response curve. Problematic frequencies will be marked in red.
2. If two axial modes are separated 20 Hz and more from each other, they are called isolated modes. In this case there will be a distinct dip in the amplitude-frequency response curve between these two modes. Problematic spacings will be marked in orange.
3. Peak and dips in the amplitude-frequency response curve cause unwanted voice and music coloration. This especially refers to the range 95-175 Hz (marked in light-grey).
4. There are essentially no speech or music colorations above 300 Hz.
Mode no. Axial room modes, Hz  
Length Width Height
Arranged in ascending order, Hz Axial mode spacing, Hz


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