a9a / Docs

GUI Reference

The a9a GUI screen layout, list columns, playback controls, Preferences, About, and the complete menu and shortcut tables.

Screen layout

When you launch the app, the list of loaded files (1) appears in the center. Selecting a single file opens the detail view (2) below it, where you can zoom into the waveform and edit precisely. Along the bottom of the window sits the transport (3) with play, pause, stop, and loop toggle controls, and on the right you can monitor playback volume with the level meters (4).

The menus appear at the top of the application window on Windows, and in the global menu bar at the top of the screen on macOS.

The whole a9a window. The list of loaded files sits in the center, the detail view below it, the playback transport along the bottom, and the level meters on the right.
Overall screen layout (1: list, 2: detail view, 3: transport, 4: level meters)

Loading files

There are two ways to load files.

  • Choose Open... in the Files menu and select the audio files (multiple selection is supported)
  • Drag files selected in Finder / Explorer onto the list area and drop them

The supported formats are wav, flac, aif, aiff, aifc, ogg, oga, mp3, m4a, and aac. For AAC (m4a / aac), HE-AAC v1/v2 can be loaded in addition to AAC-LC. A progress dialog is shown while files are loading.

Files that are already in the list, and duplicates among the files selected at the same time, are not added again.

On the first launch, and on launches after the Terms of Service have been updated, the Terms of Service screen is displayed. Review the terms and accept them to proceed.

List columns

ColumnContent
WaveformMiniature waveform, plus loop / fade / trim / reverse state icons and the per-row gain control
File NameFile name. Hovering over a row shows the full path of the source file
Bit DepthBit depth
Sample RateSample rate
ChannelsChannel count
LengthDuration
True PeakTrue peak
LoudnessIntegrated loudness (LUFS)
LRALoudness range
CrestCrest factor
A close-up of one list row. The miniature waveform in the waveform column, the loop and fade icons, and the gain control at the right end are visible.
One list row, with the loop and fade icons in the waveform column

Working in the list

ActionHow
Select one fileClick
Add to or remove from the selectionCtrl + click on Windows, Cmd + click on macOS
Select a rangeShift + click
Move the selectionUp and down arrow keys
SortClick a column header; clicking it again toggles ascending and descending
Adjust gainDrag the gain control at the right end of the waveform column on a selected row
Open a bulk dialogRight-click a row and choose Loudness... / Gain... / Fade... / Trim Silence...
Export analysis resultsRight-click a row and choose Export Analysis (CSV)... / Export Analysis (TSV)... (applies to the selected files)
Remove from the listDelete or Backspace

Files with a loop or fade-in/fade-out configured show icons; hover over them to see the current settings. Files with an active trim show a [ ] icon, and reversed files show a ◀◀ icon; hover over them to see the current state.

Removing a file only removes the list entry — the original audio file is not deleted.

Bulk dialogs opened from the right-click menu apply to the selected files, just like Selected... in the Edit menu. Right-clicking a row that is not selected opens the menu with only that row selected.

Exporting analysis results

The analysis values shown in the list can be exported as a CSV or TSV report. From Export Analysis in the Files menu, choose Selected Files (CSV)... / Selected Files (TSV)... (the selected files) or All Files (CSV)... / All Files (TSV)... (every file) and pick a destination. The selected files can also be exported from a list row’s right-click menu. If you change the file name extension to .csv / .tsv in the save dialog, that extension’s format takes precedence.

The exported columns are File Name / Bit Depth / Sample Rate (Hz) / Channels / Length (s) / True Peak (dBTP) / Loudness (LUFS) / LRA (LU) / Crest (dB) — nine in total — and the rows follow the list order. Units live in the header row and every cell holds only the number, so the report drops straight into a spreadsheet quality check. Fields with no value (Bit Depth for lossy files, LRA for short files) are left empty. True Peak and Crest are aggregates rather than per-channel values (True Peak is the maximum across all channels; Crest is computed for the audio as a whole). The output is UTF-8 with a BOM and opens directly in Excel.

Playback

Playback is available when exactly one file is selected. Use Play / Pause on the transport to toggle between playing and pausing, and Stop to stop. Each press of Loop cycles the playback loop mode.

Loop modeBehavior
SelectionRepeats the loop range configured in the detail view
AllRepeats the entire file
OffDisables loop playback

The L and R level meters on the right side of the window give you a rough view of the playback volume.

For playback behavior while a waveform selection exists, see Editing Waveforms.

Preferences

Preferences configures display, playback, and default bounce settings.

General

SettingDescription
ThemeColor scheme: System, Light, or Dark
Snap loop boundaries to nearby zero crossingsWhether loop boundaries snap to a nearby zero crossing
Silence Detection > Show silent regions in the detail viewToggles the silence display in the detail view (off by default; the same setting as Show Silence Regions in the View menu)
Silence Detection > ThresholdUpper RMS level treated as silence (dBFS, default -60)
Silence Detection > Min DurationMinimum length of a highlighted silent region (ms, default 100)
Trim MarginSilence kept before and after the audible range when trimming leading and trailing silence (ms, default 0). Also the initial value for the Trim Silence dialog in the Edit menu

Audio

SettingDescription
DeviceThe playback device
Sample RateThe device default or a supported sample rate
Buffer SizeThe playback buffer size

Bounce

Overwrite existing files by default controls whether overwriting is allowed by default when bouncing. Enabling Load bounced files into the file list (off by default) adds files written to paths not yet in the list as new rows (files written to paths already in the list are always reloaded, regardless of this setting). Write a CLI job file alongside outputs by default (off by default) is the default for Write job file alongside outputs in the bounce dialog. You can also configure the defaults for WAV, FLAC, AIFF, Ogg Vorbis, MP3, and AAC.

About

About shows the application name, its version, the engine version, the application license, and third-party licenses. On the Application License screen you can switch the display between Japanese and English.

In the tables below, the Windows and macOS columns give the shortcut on that OS. None means no shortcut is assigned, and — means the item does not exist on that OS.

MenuWindowsmacOS
a9a application menuNoYes
Files / FileYesYes
EditYesYes
ViewYesYes
TransportYesYes
HelpYesYes

On Windows, About lives in the Help menu and Preferences in the Files menu. On macOS, About and Preferences are gathered in the a9a application menu. On both OSes, the Help menu contains a9a Help, which opens the manual.

The a9a application menu (macOS only)

ItemShortcutFunction
About a9aNoneOpen the About screen
PreferencesCmd+,Open Preferences
Quit a9aCmd+QQuit the application

Files / File

ItemWindowsmacOSFunction
Open...Ctrl+OCmd+OLoad audio files
PreferencesCtrl+,—Open Preferences (on macOS it lives in the a9a menu)
Bounce > Selected...Ctrl+Shift+BCmd+Shift+BExport the selected files
Bounce > All...Ctrl+Alt+BCmd+Option+BExport all files
Export Analysis > Selected Files (CSV)... / (TSV)...NoneNoneExport the selected files’ analysis results as CSV / TSV
Export Analysis > All Files (CSV)... / (TSV)...NoneNoneExport every file’s analysis results as CSV / TSV

Edit

ItemWindowsmacOSFunction
UndoCtrl+ZCmd+ZUndo the last operation
RedoCtrl+Y or Ctrl+Shift+ZCmd+Shift+ZRedo the undone operation
Loudness > Selected...Ctrl+Shift+LCmd+Shift+LApply loudness adjustment to the selected files
Loudness > All...Ctrl+Alt+LCmd+Option+LApply loudness adjustment to all files
Gain > Selected...Ctrl+Shift+GCmd+Shift+GApply peak-based adjustment to the selected files
Gain > All...Ctrl+Alt+GCmd+Option+GApply peak-based adjustment to all files
Fade > Selected...Ctrl+Shift+FCmd+Shift+FApply fades to the selected files
Fade > All...Ctrl+Alt+FCmd+Option+FApply fades to all files
Reverse > SelectedCtrl+Shift+RCmd+Shift+RToggle reverse (reversed playback) on the selected files
Reverse > AllCtrl+Alt+RCmd+Option+RToggle reverse (reversed playback) on all files
Trim to Selection / Trim SilenceCtrl+TCmd+TTrim to the selection if one exists; otherwise trim the leading and trailing silence of the file in the detail view
Clear TrimNoneNoneRemove the trim
Trim Silence > Selected...Ctrl+Shift+KCmd+Shift+KTrim the leading and trailing silence of the selected files
Trim Silence > All...Ctrl+Alt+KCmd+Option+KTrim the leading and trailing silence of all files

View

ItemWindowsmacOSFunction
Show Details / Hide DetailsCtrl+I—Toggle the detail view
Details—Cmd+IToggle the detail view
Zoom InCtrl++Cmd++Zoom into the waveform
Zoom OutCtrl+-Cmd+-Zoom out of the waveform
Reset ZoomCtrl+0Cmd+0Reset the zoom
Full Timeline for Trimmed FilesCtrl+Shift+TCmd+Shift+TSwitch the waveform display for trimmed files
Show Silence RegionsCtrl+Shift+SCmd+Shift+SToggle the silence display in the detail view

Transport

ItemWindowsmacOSFunction
Play / PauseSpaceSpaceToggle between playing and pausing
StopNoneNoneStop playback
Loop > Loop SelectionNoneNonePlay the loop range
Loop > Loop AllNoneNoneLoop the entire file
Loop > Loop OffNoneNoneDisable loop playback

Help

ItemWindowsmacOSFunction
a9a HelpF1Cmd+?Open the built-in manual
AboutNone—Open the About screen (on macOS it lives in the a9a menu)

Running a9a Help opens the manual in the OS default browser on Windows, and in the Help Viewer on macOS. On macOS, the search field in the Help menu searches both menu items and help content.

Shortcuts outside the menus

OperationWindowsmacOSDescription
Cycle the playback loop modeCtrl+LCmd+LCycles Selection → All → Off
Remove the selected files from the listDelete / BackspaceDelete / BackspaceRemoves list entries only; source files are not deleted
Clear the waveform selectionEscEscClears the selection range
Close a dialogEscEscActs as cancel or close in most dialogs

When operations are restricted

Playback and the detail view are both available only while exactly one file is selected. While a dialog is open, the usual shortcuts and editing operations are temporarily disabled. During loading and bouncing, a progress dialog stays in front and no other operations are possible until it completes.

This page was written with generative AI.