Manual

01Start here

LOWTUNA measures the kick against the bass and chooses a correction for each kick hit. A flip that helps one bass note can hurt the next. Each hit gets its own decision.

It works from a captured section of your stems. Analyze once, then play the same section at the same place in the DAW. It is not a live, continuously adapting phase corrector.

It can help to check the kick and bass early in a mix, starting with Pure phase on. Put LOWTUNA after the processing you want measured, not automatically before every effect. If later edits change either stem, re-analyze.

1. Put LOWTUNA on the kick. Place it after the processing you want included in the measurement.
2. Give it the bass. Use a host sidechain or a second LOWTUNA instance on the bass.
3. Analyze the section. Play from just before the first hit through the last tail, then finish the capture.
4. Listen and check. Wait for the measurements, then use Correction to compare. Keep the changes that help the mix.

02Install and update

Quit your DAW and extract the download before copying the plugin.

Windows · VST3

Copy the entire LOWTUNA.vst3 item to C:\Program Files\Common Files\VST3\. Approve the Windows copy prompt if asked. Reopen your DAW and rescan VST3 plugins if needed.

Mac · Intel and Apple Silicon

The release Mac download is universal, signed and notarized. Double-click the ZIP on your Mac to extract it. Install the format your DAW uses; Logic Pro, GarageBand and MainStage use AU.

In Finder, choose Go → Go to Folder, paste the destination including the ~, and press Return. These locations install for your user account. If a folder is missing, open ~/Library/ and create Audio, then Plug-Ins, then VST3 or Components as needed.

Copy each whole .vst3 or .component bundle as it appears in Finder. Do not open Show Package Contents or copy its internal files separately. Reopen your DAW and let it scan; rescan its plugins if needed. For an AU that still does not appear, restart the Mac.

Replacing an older version

With the DAW closed, replace the old bundle in its existing installation location. Avoid duplicate copies of the same format in different plugin folders. The release retains the plugin identity used by existing projects. Keep a backup of important projects before saving them with an update.

The standalone app is optional. On Mac, copy LOWTUNA.app to Applications. The plugin inside your DAW is the normal choice for the host-timeline workflows in this manual.

03Kick and bass routing

Option 1 · Host sidechain

1. Insert LOWTUNA on the kick track or kick bus.
2. Route the bass to LOWTUNA’s sidechain input using your DAW.
3. Click the top-right SC button. Keep this instance in Kick role and select Sidechain input as the bass source.

The main input must be the kick, not a combined kick-and-bass bus. The bass input is a reference; LOWTUNA does not mix it into the kick output.

Option 2 · Two LOWTUNA instances

1. Put one instance on the bass. Open its top-right menu, choose This instance is… → Bass — feed a kick instance.
2. Put the other instance on the kick. Leave it in Kick — correct this channel role.
3. In the kick instance’s menu, select the bass instance as the source.
4. Check for a green LINK on the kick and FEED on the bass. Analyze from the kick instance.

The bass-role instance does not phase-correct the bass. Keep the DAW’s plugin delay compensation enabled for both tracks.

04Capture and re-analyze

Start just before the first kick so its attack is included. Click Analyze, start playback, and let the whole section run. Click Finish capture after the last tail. Wait until solving and playback measurement finish before judging the result.

You can arm Analyze while stopped. Stopped audio and negative timeline pre-roll do not enter the timed capture. A usable capture must be at least 0.5 seconds; the maximum is 6 minutes. Work in sections for longer songs.

A loop wrap or timeline jump ends the current capture. For a complete pass, avoid seeking and make the loop longer than the section you want to analyze.

When to re-analyze

• You replace, move, stretch or edit either stem.
• You change upstream EQ, distortion, timing, polarity, gain or routing.
• You change the project sample rate.

Saving and reopening

A completed take stores its captured audio, hits, correction choices and manual edits in the DAW project. Save after analysis finishes. On reopening, wait for the take to restore and become ready before playing or rendering. Longer captures make the project larger. Temporary Solo audition is not restored.

Very early project states that did not store captured audio need a new analysis. If the stems move to a different place in the song, re-analyze there; the correction schedule follows the captured host timeline.

05Correction and Pure phase

A lit green switch means on. After a change, wait for any background solving or measurement to finish. With Correction off, the display shows the uncorrected result rather than pretending the stored correction is audible.

What the correction methods mean

The automatic solver favours simpler useful corrections. It measures the actual captured audio and checks low-band benefit and the summed attack. These checks are not a promise of zero artifacts on every kick.

06Read the displays

Correlation

Before and After summarise low-band correlation across the measured hits. The scale runs from −1 to +1. Positive means more agreement, negative means more opposition, and zero means weak linear correlation. This is not a percentage of “perfect phase”.

Summed 30–120 Hz is the measured change in combined kick-and-bass energy in that band. It is not output gain, LUFS, or the level change of the whole mix.

At extreme cancellation, gain readouts use finite bounds such as ≥ +160 dB or ≤ −160 dB. These indicate a display limit, not an exact gain or an instruction to add that much level.

After manual edits and mode changes, Measuring playback… means the numbers are being recalculated through the scheduled playback path. Wait for that pass to finish.

Phase Sonar

Each plotted dot represents a pitched kick hit measured against the bass. A smaller radius means stronger measured correlation. Its position uses an equivalent phase angle derived from that correlation; the phase sign near the bass fundamental chooses the left or right side. This is not a spectrum or a literal phase-angle measurement at every frequency.

The radial scale adjusts to the take. Read the ring labels when comparing distances between captures; the outer ring is not always 180°.

Click a dot to inspect that hit. Use the wheel to zoom, drag to pan, and double-click to reset. Unvoiced hits can appear in the timeline without a pitched dot, so the counts need not match.

Hit Timeline

Each block is a detected kick. Its height follows kick level; the small before and after indicators show the measured relationship. Click a block to select it. Use the wheel to zoom, drag to move through the section, and double-click to fit the capture.

Green

Polarity flip.

Violet

All-pass. A green and violet combination means flip plus all-pass.

White

FIR correction.

Grey

Unchanged, including a manual Off choice.

Amber

Kick-change advisory. Re-analyze the edited material.

07Inspect and edit a hit

Select a hit in the sonar or timeline. The Inspector shows its measurements, phase curves and correction. Use the hit navigation controls to move through the take.

The plot shows phase against frequency, including the residual relationship after correction. FIR pre-ring and magnitude-deviation figures are filter checks, not a guarantee that the whole kick sounds unchanged.

Manual controls

Manual choices can make the result worse. Check the attack, body and tail in context, not just the displayed gain. Closely spaced hits with less than 30 ms of usable scoring window are left uncorrected.

08Kick timing suggestion

With Pure phase on, LOWTUNA can suggest moving the whole kick stem slightly earlier or later. The readout appears beside the main switches when the current take has a suggestion. Hover it for the sample offset and the number of hits that improve or worsen.

This is advice only. LOWTUNA does not move the kick, and Commit does not apply the suggested shift.

1. Note the direction and offset shown.
2. Nudge the kick clip or stem by that amount in the DAW.
3. Re-analyze the moved stems.
4. Check the groove against the snare and hats, especially for shifts over 5 ms.

Kick timing: no useful shift means no tested candidate passed those checks. It is not proof that the timing is perfect or that every possible offset was tested.

A smaller correction-gain number after a manual nudge does not automatically mean worse audio. Each analysis compares its corrected result with its own uncorrected kick-and-bass sum. A better starting relationship may need less correction. Compare the final sums with the same stems, gains and measurement settings.

09Commit a corrected stem

Click Commit at the bottom right to export the captured kick as a 32-bit float WAV at the capture’s sample rate. It renders the stored correction plan, including manual choices.

This keeps the rendered floating-point samples, including headroom above 0 dBFS, without converting them to 24-bit integer audio. There is no automatic normalization or added dither. The plugin receives audio from the DAW, not the source file’s format metadata, so Commit always writes 32-bit float—it does not detect and copy the original file’s bit depth or sample rate.

Processing delay is trimmed from the file. Place the exported WAV at the capture start in the DAW, including any pre-roll you captured—not automatically at bar 1 or at the first kick. It exports stereo when the captured kick has measurable Side content; otherwise it can export mono.

Once you use the printed stem, bypass or remove LOWTUNA on that playback path so you do not correct the same audio twice. Keep the original stem and project take as a backup.

Export checks

filter dev reports correction-filter magnitude deviation. It is not a complete transient or tonal-difference measurement.

off null checks the internal floating-point Correction-off path against the captured source. It is not a claim that the corrected export nulls with the original file.

Export runs in the background. Closing the editor does not cancel it; removing the plugin does.

10Theme, size and preferences

Click the LOWTUNA wordmark to open the menu. It does not cycle themes directly.

These display preferences are stored on the local machine. Theme and glow do not change any audio measurement.

11Signal path and limits

Use host delay compensation for aligned playback. Do not add another manual delay just to “cancel” the reported latency. A shifted waveform after all-pass or FIR processing does not, by itself, prove a host timing error.

Projects saved with the earlier Low only setting retain it. That control is hidden in the current editor and defaults to Off in new instances. An older project with it enabled still uses the 300 Hz crossover and reports about 46.7 ms total latency. The host’s generic parameter controls can change that saved setting; wait for re-solving and measurement afterward.

There is no promise of 100% alignment, zero artifacts or an improvement on every hit. Bass notes change, filters reshape waveforms, and the best-sounding relationship is a mix decision. Compare in context and at a sensible monitoring level.

12If something looks wrong