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Mosque Acoustic Design
From Mihrab to Minaret

Solve dome focusing, marble reflections, and PA system conflicts. Sabine calculation with faith-specific presets and ISO 3382 compliance.

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The Acoustic Challenge

Mosque geometry is acoustically hostile. Domes focus, marble reflects, and competing use-cases demand different RT60 targets in the same volume.

Dome Focusing Effects

Dome geometry creates focusing effects — sound converges at focal points, creating hot spots and dead zones across the musalla.

Marble & Stone Surfaces

Marble and stone surfaces (α ≈ 0.01–0.03 at mid-frequencies) are extremely reflective, driving RT60 well beyond speech-intelligible ranges.

Tajweed vs Khutbah

Tajweed recitation requires RT60 ≤ 1.5s for syllabic clarity, while khutbah speech needs RT60 ≤ 1.0s — competing requirements in one room.

PA System Interference

PA systems in domed spaces create comb filtering and flutter echo, making amplified speech less intelligible than unaided voice.

Uniform Sound Distribution

The musalla (prayer hall) must have uniform sound distribution so every worshipper hears the imam equally, regardless of position.

Flanking Noise Paths

Wudu areas and courtyards create flanking noise paths that raise background noise levels in the prayer hall during services.

Standards & Guidelines

ParameterTargetNote
RT60 — Khutbah-focused1.0–1.5 sSpeech clarity priority
RT60 — Quran recitation1.5–2.5 sMusical warmth for tajweed
STI — Speech≥ 0.55IEC 60268-16 'fair' minimum
STI — Recitation≥ 0.45Allows reverberant enhancement
Background noise — Prayer hallNC ≤ 30Near-silent baseline
Background noise — Ablution areasNC ≤ 40Water noise controlled

Targets based on ISO 3382-2:2008, IEC 60268-16:2020, and published mosque acoustic research. All results are advisory and require professional verification.

Interactive 3D Room Preview

See the acoustic challenge. Red surfaces are highly reflective — marble floors and concrete domes drive RT60 well above speech-intelligible ranges.

Loading 3D room preview...

Interactive 3D heatmap — red surfaces are highly reflective. Drag to rotate, scroll to zoom.

Worked Example

A 6,000 m³ dome mosque — from unintelligible to clear.

Room Specification

Dimensions: 25 m × 20 m × 12 m
Volume: 6,000 m³
Floor: Marble (α = 0.01)
Walls: Plaster on masonry (α = 0.02)
Ceiling: Concrete dome (α = 0.02)
Geometry: Central dome with pendentives

Before Treatment

Total absorption (A)230 m²
RT60 (Sabine)4.2 s
STI0.32 (bad)
RT60 = 0.161 × V / A
RT60 = 0.161 × 6000 / 230
RT60 = 4.2 s

After Treatment

Total absorption (A)690 m²
RT60 (Sabine)1.4 s
STI0.62 (good)
RT60 = 0.161 × V / A
RT60 = 0.161 × 6000 / 690
RT60 = 1.4 s

Treatment Applied

  • Acoustic plaster on dome intrados (α = 0.65 at 1 kHz) — addresses dome focusing and ceiling reflection
  • Carpet tile on musalla floor (α = 0.35) — replaces marble floor reflection in prayer area
  • Geometric wood diffusers on qibla wall (α = 0.50) — scatters imam's voice evenly across hall

Recommended Materials

Acoustic plaster

NRC 0.65

Dome intrados

Spray-applied, visually identical to lime plaster. Absorbs dome reflections without altering appearance.

Carpet tile

NRC 0.35

Musalla area

Reduces floor reflection from α 0.01 (marble) to α 0.35. Essential for prayer hall treatment.

Geometric wood diffusers

NRC 0.50

Qibla wall

Scatters sound from the imam's position, improving distribution without deadening the space.

Perforated MDF panels

NRC 0.70

Side walls (above dado)

High-absorption panels with air cavity. Hidden behind decorative mashrabiya screens.

Fabric-wrapped absorbers

NRC 0.85

Rear wall

Maximum absorption where reflections from the rear wall would cause echo at the imam's position.

Micro-perforated metal ceiling

NRC 0.60

Non-domed areas

Broad-spectrum absorption for flat-ceiling corridors and mezzanine areas.

Frequently Asked Questions

What RT60 is best for a mosque?
1.0–1.5 seconds for mosques prioritising khutbah (Friday sermon) clarity. 1.5–2.5 seconds where Quran recitation and tajweed are the primary function. Most mosques benefit from a compromise around 1.2–1.8s, achievable with targeted dome and floor treatment.
How do you treat a dome without changing its appearance?
Acoustic plaster is the standard solution — it can be colour-matched to existing lime or gypsum finishes and achieves α ≈ 0.65 at 1 kHz. Micro-perforated metal linings are another option, fitting inside the dome shell with an air gap for broadband absorption.
Can a PA system compensate for poor acoustics?
No. A PA system amplifies the direct sound, but the room's reverberant field remains unchanged. In a 4-second RT60 space, the PA makes the problem louder, not clearer. Fix room acoustics first, then design the PA for the treated room.
Does carpet in the musalla area help?
Yes, significantly. Marble flooring has α ≈ 0.01 at mid-frequencies. Carpet raises this to α ≈ 0.35 — a 35x increase in floor absorption. For a 500 m² musalla, that adds approximately 170 m² of absorption, reducing RT60 by 0.5–1.0 seconds.

Design Your Mosque Acoustics — Free

Faith-specific presets, Sabine & Eyring calculation, ISO 3382 compliance. No specialist training needed.

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