SpectraNull

SpectraNull

See the null. Hear the null.

Compare two versions of the same audio.

Load two files and hear what remains after their timing, polarity and level are matched.

When the matched files are identical, the Null is silent.

The Null is the sample-by-sample result of A − B after timing, polarity and level are matched.

Matched before subtraction

Direct sample residual

The Null comes from direct sample subtraction. Common, Only in A and Only in B come from spectral comparisons resynthesised for playback.

Null = aligned A − matched B

Cyan

Only in A

Content present in A but absent from matched B.

Coral

Only in B

Content present in B beyond the matched content in A.

Shared

Common

The spectral content retained by both matched files.

Track A, Track B and the Null share one timeline, selection and logarithmic frequency scale.

Six sources. One timeline.

Switch between A, B, Null, Common, Only in A and Only in B. The playhead, selection and channel route stay in place.

Sources

  • ∅ Null
  • A
  • B
  • A ∩ B Common
  • A − B Only in A
  • B − A Only in B

Channels

  • Stereo
  • Left
  • Mid
  • Mono
  • Right
  • Side

Null level

Boost when the residual is faint.

Boost starts at 0 dB and reaches 36 dB. An always-on −1 dBFS hard limiter keeps monitor output bounded.

One comparison. Three views.

Use Spectra to locate changes in time and frequency, Spectrum to compare frequency levels, and Waveform to inspect timing.

Spectra

Time against logarithmic frequency.

Amplitude is encoded by one absolute dBFS colour scale. Every frequency doubling occupies the same height, and the full-resolution analysis remains available as you zoom.

  • 48 bands per octave
  • 6.25 ms retained columns
  • 30, 60, 90 or 120 dB display range
Unified, Stereo and M/S layouts are available in every display.

Spectrum

Full file, live level and dual peaks.

The source spectra combine a static full-file response, the live spectrum and a Type II PPM peak trace. The Null is centred on 0 dB with separate positive and negative peaks.

  • Positive peak: energy only in B
  • Negative peak: energy only in A
  • Logarithmic frequency axis
The Null spectrum keeps additions and removals on opposite sides of zero.

Waveform

One timeline for every view.

The bottom ruler shows the shared playhead, selection and loop. Click to position, drag to select and drag either edge to adjust it. Timing, frequency and level read-outs remain directly below.

  • Space starts from the cursor
  • Loop starts from the selection boundary
  • Return stops and goes to the loop start or beginning
The timeline, selection and cursor remain synchronised while monitor sources change.

View every display as Unified, Stereo or M/S.

The selected layout applies to A, B and the active monitor source.

Move through revisions without reopening Finder.

Each side keeps its own folder, file list and sorting order.

  1. 01

    Open a file or a folder

    Both actions stay visible. Folder lists show only loadable mono and stereo audio.

  2. 02

    Select the next revision

    Sort by name, modification date, creation date or size in either direction.

  3. 03

    Drag in or drag out

    Drop audio from Finder into either pane, or drag the document icon into another app.

  4. 04

    Reload when ready

    A genuine file revision shows one red Reload button. Nothing reloads automatically while an export is still being written.

Local files. Local processing.

Decoding, alignment, analysis, matching and playback all run on your Mac.

Now in TestFlight.

SpectraNull is being tested with a limited group before its Mac App Store release.