Music Production
Find the correct delay intervals (1/4, 1/8, dotted notes) and reverb pre-delay times at any BPM.
Keep your reverb tails and echoes in perfect rhythm with your track.
Reverb delay time (pre-delay) is the gap between the original sound and the first reflections in a reverb effect. This parameter profoundly affects how natural and spacious reverb sounds, separating the direct signal from early reflections. Pre-delay prevents the reverb from 'clouding' the original sound, maintaining clarity and definition in a mix. In real acoustic spaces, sound travels to room boundaries and back, creating measurable delays before reflections reach the listener. Short pre-delays (0-20 ms) simulate small, untreated rooms or hard surfaces close to the sound source. Longer pre-delays (50-200 ms) simulate larger spaces like concert halls or cathedrals. Using appropriate pre-delay helps instruments maintain presence and clarity while benefiting from reverb's spaciousness and dimension.
Pre-delay is calculated based on the distance sound must travel to reach reflecting surfaces and return. The formula uses the speed of sound (approximately 343 m/s at 20°C) and distance measurements. You input the distance from the sound source to the nearest reflecting surface, and the calculator determines the time it takes for sound to travel there and back. For example, a 5-meter distance creates approximately 29 ms of pre-delay. In digital reverb plugins, you typically set pre-delay as a fixed millisecond value, while the calculator helps you understand the physical reality behind pre-delay timing.
Pre-delay (ms) = (Distance × 2) / Speed of Sound. Using 343 m/s: Pre-delay = (Distance in meters × 2 ÷ 343) × 1000. For 2 meters: (2 × 2 ÷ 343) × 1000 ≈ 11.7 ms. The ×2 accounts for round-trip distance (to surface and back).
Vocals typically sound best with 20-40 ms pre-delay, which maintains vocal clarity while adding spaciousness. This range is natural-sounding for most room simulations and prevents the reverb from obscuring the lead vocal performance.
Yes, syncing pre-delay to beat subdivisions (eighth notes, sixteenths) often sounds more musical. For 120 BPM, an eighth note is 250 ms, a sixteenth is 125 ms. Experiment with different subdivisions to find what fits your mix.
Insufficient pre-delay is often the culprit. If early reflections hit too quickly, they cloud the original sound. Try increasing pre-delay to 30-50 ms to separate the direct signal from reflections.
Technically yes, but it sounds unusual. Typically pre-delay is 5-20% of the decay time. Longer pre-delay with short decay can work for special effects, creating an isolated early reflection before a short reverb tail.
