See how your room’s proportions affect acoustic performance. Compare to Bolt Area ideal ratios and known good room dimensions.
Room dimensions
Bolt Area Rating
excellent
Ratio: 1 : 1.50 : 2.13
(Height : Width : Depth)
Bolt Area chart
Recommended room ratios
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Try the Atuund WorkstationRoom modes distribute based on dimension ratios. When two dimensions are similar or one is a multiple of another, modes pile up at the same frequencies, creating severe peaks. Well-proportioned rooms spread modes more evenly across the frequency spectrum, giving smoother bass even before treatment or placement optimization.
Richard Bolt’s research identified a region of dimension ratios where room modes distribute most evenly. The “Bolt Area” is defined by normalized ratios (smallest dimension = 1) where the middle ratio falls between 1.1–1.9 and the largest between 1.4–2.8. Rooms inside this area tend to have better low-frequency behavior.
Several researchers have published ideal ratios. Common recommendations include 1:1.14:1.39 (IEC standard), 1:1.28:1.54 (Sepmeyer B), and 1:1.40:1.90 (Louden). All fall within the Bolt Area. In practice, any ratio inside the Bolt Area is good. Avoid cubes and rooms where one dimension is exactly double another.
Not at all. Room ratios describe the starting conditions, not the outcome. Good speaker placement and bass treatment can overcome poor proportions. Many excellent listening rooms and studios exist in spaces with non-ideal dimensions. Ratios matter most in untreated rooms.
Atuund uses finite element method (FEM) modal analysis to model room acoustics. Built for hi-fi enthusiasts, home theater builders, and anyone who wants better sound from their speakers.