Add smooth volume swells or rhythmic pulses without changing pitch or duration. Adjust rate, depth, mix and pulse shape live, then preview and download the actual WAV.
No file selected.
Up to 128 MiB per file; decoded audio up to 256 MiB (about 23 min mono / 11½ min stereo). Formats depend on your browser's decoder. Working audio and WAV exports use 48 kHz.
Choose audio to begin. Nothing plays automatically.
No audio loaded
Your waveform will appear here.
Load audio to choose a section.
Click the waveform to seek the source; use Play/Pause, exact time or jump controls. Tremolo changes apply live while playing. Duration stays unchanged; the waveform remains the original source. The source ruler always shows original source time.
Playback stopped.
Change settings while playing to hear tremolo live. Uncheck to compare original audio; exports always use the selected effect.
Quick sliders pause for exact values finer than their steps; your entered value remains usable.
The original file stays unchanged.
Input up to 128 MiB; source and output float audio each have a 256 MiB limit. Output keeps the source sample count. Live controls use a short smoothing transition and keep oscillator phase continuous. The source waveform stays unchanged; the generated waveform shows the actual effect.
Create a WAV to preview the actual adjusted file.
48 kHz · 16-bit PCM WAV · original channel count and frame count. Stereo-linked amplitude modulation with no resampling, normalization or make-up gain. Source peaks already beyond PCM range can still clip and are counted. No automatic fade or appended tail. Square gating has hard edges and can click or add harmonics. Tags/artwork are omitted.
Your audio is never uploaded to any server. Decoding, tremolo processing, playback and WAV encoding happen locally in your browser using self-hosted code. Source files remain unchanged, with no account or audio history.
Tremolo varies amplitude (volume), while vibrato varies pitch. This tool multiplies both stereo channels by the same gain envelope without resampling. The original frame count, duration, pitch timing and channel relationship remain. Modulation can add sidebands, especially with hard square pulses.
The wet gain moves from 1−depth/100 to 1. Blending the original gives a final minimum gain of 1−(depth/100 × mix/100). For example, 60% depth and 50% mix ranges from 70% to 100% of source amplitude. Zero depth or zero mix retains the decoded samples before WAV quantization. No automatic make-up gain or normalization is added.
Sine gives a smooth swell, triangle gives a linear rise/fall, and square alternates between full and minimum amplitude at 50% duty. Square edges are intentionally abrupt and can click or add harmonics on sustained tones; use sine or triangle for gentler movement. The initial fixed-setting cycle starts at full amplitude.
Yes. Rate, depth, mix and shape update the playing local AudioWorklet without restarting. A short smoothing transition keeps parameter and shape changes gradual, and oscillator phase remains continuous. Square cycles still have hard edges. Export applies current fixed settings; it does not record live knob movements.
Fixed-settings modulation is anchored to source time, so seeking matches the corresponding section of a fixed-settings export. Live control changes have smoothing and phase history that a fresh export does not reproduce. The original sample count is retained, with no automatic fade or appended tail at the end. Source and result players have independent seek controls.
Rate 0.1–20 Hz, depth and mix 0–100%. One mono/stereo file up to 128 MiB, decoded at 48 kHz within a 256 MiB float-buffer budget; output has its own 256 MiB float budget. Available device memory can impose lower limits. Live AudioWorklet needs a supported browser and HTTPS or localhost. Export is 48 kHz 16-bit PCM WAV; tags/artwork are omitted. Out-of-range source samples may still clip and are counted. Stop export terminates the local worker.
