SOLIPSIUMAlpha

SOLIPSIUM Super resolution audio engine

Free audio tool

Measure and remove the DC offset of a recording.

A recording that sits a little above or below zero wastes headroom and can click at an edit. Your browser measures each channel's offset and takes it out. Nothing is uploaded.

Drop a recording here

Your browser does the work on this device. Nothing is uploaded.

WAV, MP3, M4A, FLAC, OGG, Opus and more, up to 30 minutes or 200 MB.

Choose a file

What it is

A wave that is not centred on zero.

Some recorders and sound cards add a small, steady voltage to everything they record. The wave then rides above or below the middle line.

Lost headroom.

Peaks on one side reach full scale sooner, so the file clips earlier when it is turned up.

Clicks at edits.

A cut or a fade that starts away from zero jumps, and the jump is a click.

Measured, then shown.

When the file opens, the tool shows each channel's average as a sample value and in dB below full scale.

How it works

The average comes out.

Each channel's average is subtracted from every sample, so the wave centres on zero. Nothing else in the sound changes.

  1. Open the file.

    The offset of each channel is measured at once.

  2. Remove it.

    With the box ticked, a high-pass at 10 Hz also takes out an offset that slowly drifts, far below anything you hear.

  3. Save it.

    As an MP3 at 192 kbps or a 16-bit WAV, at the file's own sample rate.

Questions

About DC offset.

How big an offset matters?

A few thousandths of full scale is common and harmless to the ear. It matters most before you edit, normalize or turn the file up.

Can I hear an offset?

Not on its own: it is not a sound. You hear its effects: a click where an edit starts, or clipping sooner on one side.

Will the high-pass change the voice?

At 10 Hz it sits far below a voice or an instrument, so they keep their sound.

Does the repair remove offset too?

This tool is for offset alone. For noise, hum and clipping, drop the recording on the home page.

Is my recording uploaded?

No. Your browser opens the file and does the work on this device; nothing is sent to Solipsium. Checking a recording for noise, hum and clipping is another page: the home page checks it in your browser too.

Free audio tools

Related free tools.

For levels and low sound.

A wave that clipped?

An offset can make one side clip first. Drop the recording on the home page to check it for clipping, noise and hum, and hear its first 20 seconds repaired.

Check a recording

The check and the 20-second try need no account.