RACK/LEVEL & SPL
dmaxd_{max}

Maximum throw distance

Find how far your system can go without losing its voice.

Inputs

YOUR SYSTEM
dB
90150
dB
60125
dB
020

Result

METER
Estimated maximum throw
25.1m
To reach your target with headroom in reserve
Distance budget
28.0dB
Headroom reserve
6.0dB
SPL at 10 meters
110.0dB
Diagram view
SOURCELISTENER96.0 dB25.1 macoustic centerlistening position
Usable throw distance: Free-field model

How it works

Know when to add a delay speaker.

Subtract your listening target and headroom from the available source level. That remaining level budget translates to distance using inverse-square attenuation.

The formula

d=10Lmax⁡−Ltarget−H20d = 10^{\frac{L_{\max} - L_{\text{target}} - H}{20}}
  • Lmax⁡L_{\max} — maximum SPL at 1 m1\,\text{m}
  • LtargetL_{\text{target}} — desired listener SPL
  • HH — headroom reserve in dB\text{dB}

Worth knowing

Every extra 6 dB of source output approximately doubles your reach. Distributed loudspeakers can provide more consistent coverage than pushing the main system harder.

Assumptions

A point-source far-field estimate. Line arrays, atmospheric absorption, obstacles and rooms can behave differently. Maximum SPL specifications are not always measured the same way.

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