Music Production
Convert distance offsets to delay time in milliseconds and samples.
Align speakers or mics for phase accuracy.
Speaker delay distance accounts for the physical distance between speakers and the listening position, crucial for phase alignment in multi-speaker systems. When speakers are at different distances from the listener, sound from farther speakers arrives later, creating phase issues, comb filtering, and uneven frequency response. Audio engineers add digital delay to closer speakers to compensate, making all speakers arrive simultaneously. This is fundamental in surround sound mixing, live sound reinforcement, and speaker array design.
Sound travels at ~343 meters per second. Calculate the time delay: delay = distance ÷ speed of sound. For example, if one speaker is 1 meter away and another is 3.43 meters away (3.43 meters farther), sound from the distant speaker arrives 10 milliseconds later. Adding 10 ms delay to the closer speaker compensates, aligning both signals in time. Frequency-dependent phase issues are resolved when all speakers reach the listener simultaneously.
Delay (ms) = Distance Difference (m) ÷ 343 m/s × 1000. Or simplified: Delay (ms) ≈ Distance (meters) × 2.915.
Delays larger than 5-10 ms become clearly audible as timing misalignment. Below 5 ms, humans struggle to detect time differences, though subtle comb filtering occurs. For critical listening, compensate all delays; for casual listening, tolerances up to ±5 ms are acceptable.
Phase is the timing relationship between waves. When speakers are equidistant, their waves align (in-phase), reinforcing each other. If distances differ, one wave arrives later, creating phase shift. At certain frequencies, out-of-phase signals cancel (destructive interference), creating nulls. Adding delay to the closer speaker re-aligns phases.
Subwoofers should generally be delayed relative to the main speakers, not part of the same delay group. Use a slightly longer delay for the subwoofer to account for its typical placement (corner or back of room). Experiment with +5 to +20 ms additional delay on the sub for tight bass integration.
Insert a delay/latency plugin on the closer speaker's channel (usually a simple delay with no feedback). Set delay time in milliseconds to match the calculated distance difference. Many mixing consoles have dedicated delay plugins. Ensure you're delaying audio channels, not speakers themselves—speaker-level delay isn't possible.
