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Tap tempo BPM calculator and beats-per-minute to milliseconds converter. Sync delay, loops, and metronome timing for music production workflows.
Calculate delay and reverb times in milliseconds synced to tempo and BPM. Find quarter, eighth, and dotted note delay values for any song speed.
Convert between audio sample rates including 44.1 kHz, 48 kHz, 96 kHz, and 192 kHz. Check file duration and sample count when changing rates.
dB compares a value to a reference. Power uses 10×log₁₀; voltage and SPL use 20×log₁₀ because power ∝ voltage².
dB = 10 × log₁₀(P/Pref); dB = 20 × log₁₀(V/Vref)Uncorrelated sources do not add linearly. Convert each level to power, sum, then convert back to dB.
Total dB = 10 × log₁₀(Σ 10^(dBi/10))Point source SPL drops ~6 dB per doubling of distance in free field conditions.
ΔSPL = −20 × log₁₀(d₂/d₁)Updated: July 2026
At 2 meters, expect roughly 84 dB; at 4 meters, ~78 dB — plan amplifier headroom for venue depth.
Two equal uncorrelated 100 dB sources combine to ~103 dB, not 200 dB — logarithmic addition prevents absurd totals.
−6 dB halves voltage (~50% perceived loudness change depending on program material); +6 dB doubles voltage.
Use logarithmic power sum. Equal levels add +3 dB; very unequal levels are dominated by the louder source.
Voltage, SPL, and amplitude use 20×log₁₀. Power and energy use 10×log₁₀. Mixing formulas gives wrong results by a factor of two in dB.
Decibels express ratios on a logarithmic scale used in audio, acoustics, and electronics. Calculate dB from power or voltage ratios, combine multiple sources, and estimate sound pressure level (SPL) change with distance.