Project Optional. Used for the PDF report header.
Speaker
SPL targets
Results
Inputs
Calculated
How to read this Background on the inputs, the chart, and the results — collapse if you don't need it.
About the inputs
Speaker sensitivity is the SPL the speaker produces with one watt of input, measured one metre away on-axis. The 1 W / 1 m reference is standard; the 2.83 V / 1 m reference is identical at 8 Ω but reads 3 dB optimistic at 4 Ω, where 2.83 V delivers 2 W. In-wall mounting adds about 6 dB across the band — loading the speaker into half-space (2π) rather than free air (4π). Crest factor is the gap between the sustained RMS level and short-term peaks; cinema content typically sits around 20 dB.
About the chart
The two curves trace what the speaker and amplifier deliver across distance. Solid is short-term peaks, dotted is sustained output. SPL falls 6 dB every doubling of distance, the inverse-square law, which gives the characteristic decay shape. The dashed horizontal line is your peak SPL target. The vertical marker is your listening position: where it crosses the curves is what reaches the seat. The gap between the curves is the crest factor.
About the results
Status badges show whether the system meets your nominal RMS and peak targets at the listening distance. Required power is given two ways. Continuous (RMS) is what the amplifier must sustain to hold the nominal level. Peak is the brief burst needed to reproduce crest peaks. They differ by the crest factor: at 20 dB, peak is 100× continuous. The margin compares the amplifier’s effective power at your speaker’s impedance with what is required. A positive margin is power in hand.