The Correct Way to Convert Milliseconds to Samples

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Recording audio at home for personal or professional reasons leaves studio musicians with a larger challenge than they might realize. The quality of recordings usually has to do with the skills of the recorder rather than the equipment itself, which means that proper recording techniques must be set in place to record a song, vocals, or instruments correctly. Improving audio sound quality can be done by delaying some recording equipment through the conversion of milliseconds to samples. Learn more about how to implement this technique below with the following formula.

Improve Audio Recordings by Applying a Software-based Sample Delay

When recording multiple sources—and especially in live recording situations—recorders sometimes need to apply a software-based sample delay to align those multiple sources and adjust the amount of latency. Usually, these types of delays are set in milliseconds to make the calculations easy on the recorder. For example, one millisecond roughly equals one foot of distance. However, some software packages don't offer a millisecond option. Recorders will have to do the math themselves, but converting samples is one ​cost-free way to improve the overall recording experience.

Converting to Samples in the Studio

To calculate sample length in milliseconds, recorders first need to know the sample rate of the recording that they are mixing. For example, say that the recording the recorder is mixing is at 44.1 kHz, which is standard CD-quality. If the recorder is mixing at 48 kHz or 96 kHz, that number should be used.

  • The formula is simple:
    • Milliseconds times the sample rate = # of samples
    • In the example, if the delay between a pair of room microphones and a soundboard feed in the record's home studio is 17 milliseconds of delay (based 17 feet of distance), the formula becomes:
    • 17 times 44.1 = 749.7 samples
    • In this case, the recorder enters a sample delay of 749.70 samples into the software for the closest source to time-align the sources.
  • It's equally easy to calculate how many milliseconds are in a number of samples. In this case, they use the following formula:
    • Samples divided by ​the sample rate = milliseconds
    • Using the example, the recorder divides 749.70 by 44.1, which brings it back to the original number, 17 milliseconds.

Using these simple formulas, recorders can easily hand-calculate the relationship between samples and milliseconds, which may come in handy when mixing in a home studio.

Delays in Live Performance

Sometimes at live performances, speakers are arranged at various distances from the stage on the walls of the auditorium. The delay of the sound coming from the stage mixed with the un-delayed sound coming from the speaker on the wall near someone can cause sound muffling and degrade listening experience. This is avoided when the sound technician (or someone if it is their band) enters a delay in the speakers based on how far they are positioned from the stage in feet, remembering that one foot of distance equals approximately one millisecond.