Music Production, Tempo & Audio Calculation Guide

📚 Overview

Music and audio work runs on a small set of formulas. Tempo decides how long a delay or a bar lasts, equal temperament decides the frequency of every note, and the decibel scale decides how loud things sound and how much amplifier power you need. Knowing these relationships helps you set up effects that sit in the groove, tune accurately, size a sound system, and plan storage for recordings.

📐 Tempo-Synced Delay Time & Equal-Temperament Frequency

A quarter note lasts 60,000 / BPM milliseconds. A dotted note multiplies that by 1.5 and an eighth note by 0.5. For pitch, each semitone multiplies frequency by 2^(1/12) and MIDI note 69 is A4 at 440 Hz.

🔢 Worked Example

Scenario: Setting a dotted-eighth delay on a guitar track at 90 BPM, then finding the frequency of the note E4.

• Tempo: 90 BPM
• Note factor: dotted eighth = 0.75 of a quarter
• Pitch: E4 (MIDI 64)
• Reference: A4 = 440 Hz

1. Quarter note = 60,000 / 90 = 666.67 ms
2. Dotted eighth = 666.67 × 0.75 = 500 ms
3. MIDI 64 is 5 semitones below A4 (MIDI 69)
4. Frequency = 440 × 2^(−5/12) = 440 × 0.7491 = 329.63 Hz

💡 Pro Tips

• Doubling the distance from a speaker lowers its level by about 6 dB in open space, so moving a listener back needs far more power to keep the same volume.
• Decibels add logarithmically: two equal sources are only 3 dB louder than one, and you need roughly ten times the power for a 10 dB increase.
• Lower audio buffer sizes cut monitoring latency but raise CPU load. Track at a small buffer and mix at a large one.
• Record at 24-bit to leave headroom, and remember that uncompressed stereo at 48 kHz and 24-bit uses roughly 17 MB per minute per stereo track.

🧮 Music & Audio Calculators (18)

Put the formulas above into practice with these free tools:

❓ Frequently Asked Questions