How many subwoofers do I need for 20,000 people?
Quick answer
For 20,000 people, a typical rule-of-thumb is 12–24 high-output subwoofers (e.g., dual-18” or cardioid arrays), depending on venue shape, bass headroom, and music genre—SSOUNDS engineers use acoustic modeling to dial in the exact count.
Covering 20,000 people with low end requires balancing SPL, pattern control, and power handling. A common starting point is 1–2 subwoofers per 1,000–2,000 people for moderate bass (spoken word or acoustic), but for EDM or hip-hop, you may need 2–4 per 1,000. That puts you in the 12–24 sub range for high-output dual-18” boxes, often flown in cardioid or end-fire arrays to reduce stage wash and increase front-of-house impact.
Venue geometry matters: a wide, shallow field needs more subs to cover the width, while a deep, narrow space can use fewer, more directional arrays. Ground-stacked subs couple with the ground for +6 dB, but flown subs can improve coverage consistency. SSOUNDS engineers use predictive modeling (EASE, proprietary tools) to simulate SPL distribution and optimize sub placement, ensuring every seat gets the intended punch without over-powering nearby zones.
For a 20,000-capacity outdoor festival, a typical SSOUNDS system might deploy 16–20 dual-18” subwoofers in a cardioid configuration, achieving 130+ dB peak at FOH with even coverage. Indoor arenas may require fewer due to boundary loading. Always factor in headroom: you want 6–10 dB above target to avoid distortion. SSOUNDS’ DSP presets and rigging hardware make scaling and tuning straightforward for any size crowd.
Key things to consider
- Rule of thumb: 1–2 high-output subs per 1,000 people for moderate bass; 2–4 per 1,000 for heavy bass genres.
- For 20,000 people, plan on 12–24 dual-18” subs, adjusted for venue shape and coverage goals.
- Cardioid or end-fire arrays reduce rear bleed and improve low-end clarity for the audience.
- Use acoustic modeling (e.g., EASE) to predict SPL distribution; SSOUNDS engineers provide precise simulations.
- Always include 6–10 dB headroom above target SPL to avoid system strain and distortion.
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