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Calculate final drive ratio, engine RPM at speed, and optimal gear spacing. Plan transmission ratios for highway cruising and acceleration goals.
Estimate turbocharger sizing from engine displacement, RPM, and target boost. Free turbo sizing calculator for performance builds and forced induction planning.
When input exceeds threshold, excess level is reduced by ratio. 4:1 ratio means 4 dB input above threshold produces 1 dB output above threshold.
GR = (Input − Threshold) × (1 − 1/Ratio)Below threshold, output equals input (no compression). Above threshold, output increases at 1/ratio of the rate input increases.
Output = Input − GR (when Input > Threshold)Apply makeup gain to restore perceived loudness after compression. Typical: match peak or RMS level to uncompressed signal.
Output_final = Output + Makeup gainUpdated: July 2026
Input peaks 10 dB above −20 dBFS threshold → 7.5 dB gain reduction. Peaks compressed from +10 to +2.5 dB relative to threshold.
Light 2:1 on drum bus with −10 dB threshold tames transients without audible pumping — 3 dB GR on loudest hits.
Effectively brick-wall above threshold. Input 5 dB over threshold with 20:1 → 4.75 dB GR, output only 0.25 dB above threshold.
Audio compressors reduce dynamic range by attenuating signals above a threshold. Enter input level, threshold, ratio, and knee settings to calculate output level, gain reduction in dB, and effective compression for mixing decisions.