Overview
Time and Frequency Sync is a high-precision calculator for music producers, beatmakers, and mixing engineers: BPM-synced delay times, acoustic reverb decay, harmonic frequency values, and sample repitch math, all with real-time audio audition so you can hear a value before you dial it into your DAW.
It runs entirely client-side in your browser. There is no server processing and no file upload — every calculation and every audio preview happens locally and instantly, and no account is required to use it.
Full Time Matrix
Calculates straight, dotted, and triplet time divisions from 4 bars down to 1/128th notes, based on your project tempo. Click any millisecond or Hz value to copy it. Click the speaker icon on any row to hear an actual echo at that exact musical division.
Delay Studio
Auto (BPM-synced) mode: choose a note length (1/1 down to 1/32), choose Straight, Dotted (×1.5), or Triplet (×0.667), and optionally add an Analog Swing/Drift offset of up to ±25 ms for a looser, more humanized delay feel. Audition Delay Echo plays a percussive test signal through a real-time feedback delay line with tape-style high-cut filtering, at the exact time you've dialed in.
Manual Timer mode works the other way around: enter an arbitrary millisecond value (for example 375 ms) and it reverse-calculates the equivalent tempo for quarter-, eighth-, and sixteenth-note delays at that timing.
Reverb Decay and Pre-Delay
Locks reverb decay time (RT60) and pre-delay to musical bars and beats, so a reverb tail doesn't bleed past a bar line or muddy the low end. Decay time is calculated from your tempo and a chosen bar length; pre-delay is calculated the same way down to a 1/64 note. Built-in space presets: 1/4 bar for tight percussion, 1/2 bar for snare and synth clarity, 1 bar for a standard vocal or snare tail, 2 bars for lead instruments, and 4 bars for large cinematic spaces. Audition Reverb Space Decay generates a synthetic impulse response matching the exact decay you've set, so you can hear it before committing.
Key and Harmonic Frequency Radar
Converts any note to its exact frequency in Hz using standard concert pitch (A4 = 440 Hz), then shows the first through eighth harmonics of your chosen root note, each with its own tone-preview button. A full eight-octave frequency grid is also shown, filtered to your selected scale.
Sample Repitch Engine
Two directions: give it an original BPM and a target BPM and it returns the semitone shift, the cent offset, and the resulting playback-rate percentage needed to retime a sample. Or give it a manual semitone offset and it returns the new BPM that offset produces. Useful for figuring out exactly how far a sample needs to be pitched to match a different project tempo, or vice versa.
Access
Free, and no account is required — the tool is fully usable the moment you open it.