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Studio / Calculators

Plain maths for the studio

Delay time from tempo

BPM

Quarter note = 60,000 ÷ BPM

1/4500 ms
1/8250 ms
Dotted 1/8375 ms
1/8 triplet166.7 ms
1/16125 ms

Room modes

m
m
m

First axial mode = 343 ÷ (2 × side) · speed of sound 343 m/s at 20 °C

Length mode42.9 Hz
Width mode53.6 Hz
Height mode68.6 Hz

Buffer latency

samples
kHz

Latency = buffer ÷ sample rate · round trip doubles it · converters and drivers add more

One way5.3 ms
Round trip (buffers only)10.7 ms

Every number above is worked out on this page from what you type · the shown values are for 120 BPM, a 4.0 × 3.2 × 2.5 m room and 256 samples at 48 kHz

Where the formulas come from, checked 2026-10-08. Delay: one minute is 60,000 ms, so a beat lasts 60,000 ÷ BPM. Room modes: the general mode formula is in Indiana University’s acoustics primer, and the first axial mode of one side is the case with a single index; GIK Acoustics works the same example (a 17 ft room, about 33 Hz). Speed of sound: 331.4 + 0.6 × 20 °C ≈ 343 m/s (HyperPhysics). Latency: double the buffer and divide by the sample rate for the round trip, before converter and driver delays (Focusrite, Sound On Sound).