Choir Mixer
Administrator's Guide
For WordPress site owners and Choir Mixer editors
Version 4.0
choirmixer.ca
Dave Kauffman© 2026 davekauffman.ca
Choir Mixer Administrator's Guide2

About This Guide


This guide is for the people who set up and maintain Choir Mixer — not the singers who use it to practice, but the administrators who make it available to them.

There are two distinct administrator roles, and this guide has a section for each.

The WordPress site owner installs the plugin, adds Choir Mixer to a page, and keeps the software up to date. They need access to the WordPress dashboard and some familiarity with how WordPress pages work. They do not need to know anything about music.

The Choir Mixer editor adds songs, uploads audio files, and places phrase markers so that singers can navigate the music. They work entirely within Choir Mixer itself — no WordPress access is needed. They are typically the choir director, rehearsal pianist, or someone the director trusts with the repertoire. They do not need to know anything about web development.

These two roles can be the same person, or different people. The guide covers each in a separate section.

Overview


Choir Mixer is a WordPress plugin that embeds a multi-track audio learning tool in any page or post on your site. Singers visit the page, hear the tracks for their choir's repertoire, and use the controls to practice at their own pace.

The song library — which songs are available, where their audio files are, and where the phrase markers fall — is maintained by the Choir Mixer editor through a built-in admin interface. The editor does not need to log in to WordPress to do this work; they enter a private key sequence directly in the player.

Audio files can be hosted anywhere that is publicly accessible, but using your WordPress Media Library is the most straightforward approach and avoids most common problems.

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Part One — For the WordPress Site Owner

Installing the Plugin


Choir Mixer is distributed as a zip file. To install it, you will need access to the WordPress dashboard with a user account that has permission to install plugins.

1.In your WordPress dashboard, go to Plugins → Add New → Upload Plugin.
2.Click Choose File and select the choirmixer.zip file.
3.Click Install Now. WordPress will upload and expand the zip file.
4.Click Activate Plugin.

On activation, Choir Mixer automatically uploads the bundled audio files to your WordPress Media Library, and writes a default configuration file to wp-content/uploads/choirmixer/. You will see the files appear in your Media Library under the name "Keep On (Going)."

After activating, visit any page in the WordPress dashboard — the admin bar, your posts list, or anywhere else — before loading the Choir Mixer page for the first time. This gives WordPress a chance to finish linking the audio files to your site's URLs. It only takes a moment.

Adding Choir Mixer to a Page


Choir Mixer is added to any page or post using a shortcode. Create or edit a page in WordPress, and place the following shortcode in the body:

[choirmixer]

Publish or update the page. Choir Mixer will appear at that position when visitors view the page.

Adjusting the height

By default, Choir Mixer is displayed at 720 pixels tall, which comfortably fits the player and its controls on a desktop screen. If you need more or less space — for example, if your page template has a narrow column, or if you expect many tracks — you can set the height explicitly:

[choirmixer height="900"]

On mobile devices, Choir Mixer expands to fill the full screen height automatically, regardless of the height setting.

Opening in a full browser tab

Singers can click the small expand icon (⤢) in the upper right corner of the player to open Choir Mixer in a full browser tab. This is particularly useful on smaller screens or when working with loop markers that require precise placement. No configuration is needed — this works automatically.

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Part One — For the WordPress Site Owner (continued)

Upgrading the Plugin


When a new version of Choir Mixer is available, you upgrade it by uploading the new zip file — the same way you installed it.

1.Go to Plugins → Add New → Upload Plugin.
2.Select the new choirmixer.zip file.
3.Click Install Now. WordPress will tell you the plugin is already installed and offer a Replace current with uploaded button. Click it.
4.Click Activate Plugin.

Your song configuration, markers, and Media Library files are stored in wp-content/uploads/choirmixer/, not inside the plugin folder. They are not touched during an upgrade.

Where Things Are Stored


Understanding where Choir Mixer stores its data will help you if you ever need to troubleshoot, back up, or move the site.

Song configuration — all songs, track URLs, and markers are stored in a single file: wp-content/uploads/choirmixer/choirmixer-config.json. This file is plain text and can be opened in any text editor. It is the most important file to back up.

Audio files — if you uploaded audio through the Choir Mixer editor (by pasting URLs from your Media Library), the files are in wp-content/uploads/ alongside all other WordPress media. If you hosted audio elsewhere, it stays wherever you put it.

Singers' personal settings — volume levels, loop positions, and playlists are stored in each singer's browser, on their own device. They do not touch your server. You cannot see or reset them.

Giving the Editor Their Code


The Choir Mixer editor enters a private key sequence to access the song management interface. That sequence is the word ADMIN, typed anywhere on the Choir Mixer page while the player is open. The letters do not appear on screen; just type them and the admin interface will appear.

Share this key sequence privately with whoever will be maintaining the song library. It does not need to be changed between editors, but if you want to restrict access in the future, you would need to update the plugin.

Note: The admin key sequence gives full access to add, edit, and delete songs and markers. Share it only with people you trust to manage the choir's repertoire.
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Part Two — For the Choir Mixer Editor

Entering Admin Mode


Open the Choir Mixer page in your browser. With the player visible, type the word ADMIN on your keyboard — just the five letters, one after another, within about two seconds. The letters do not appear on screen and nothing special needs to be focused.

When admin mode activates, a purple banner appears at the top of the player reading ⬡ Admin Mode — click to exit. The song list and marker row also change to show editing controls.

To exit admin mode, click the purple banner, or type ADMIN again. If you have unsaved changes, you will be asked whether to save or discard them before exiting.

Changes save automatically. Most actions — adding a marker, moving a marker, editing a song — save immediately without any extra step. The status indicator at the top of the player shows "Saving…" briefly when this happens. You do not need to click a save button for day-to-day work.

Preparing Your Audio Files


Before adding a song to Choir Mixer, you need the audio files for each vocal part, and optionally a sheet music PDF. Choir Mixer needs a direct URL to each file — a web address that, if you pasted it into a browser, would download or play the file directly.

Using the WordPress Media Library

The most reliable approach is to upload your audio files to the WordPress Media Library. Files in the Media Library are hosted on your own site, which avoids the access problems that can arise with files hosted elsewhere.

1.In the WordPress dashboard, go to Media → Add New.
2.Upload your MP3 files — one per vocal part.
3.Click on each uploaded file to open its details. Copy the File URL shown in the right-hand panel. It will look something like https://yoursite.com/wp-content/uploads/2026/06/soprano.mp3.
4.Keep these URLs — you will paste them into Choir Mixer in the next step.

Using files hosted elsewhere

You can use audio files hosted on any publicly accessible server. The URL must be a direct link to the file itself, not a sharing page. Google Drive, Dropbox, and similar services typically require extra steps to generate direct links — if in doubt, uploading to the Media Library is simpler.

Cross-origin audio. If Choir Mixer cannot load an audio file, the most likely cause is that the file's server does not permit requests from another website. This is a standard web security feature. Files in your WordPress Media Library will always work. Files on other servers may or may not, depending on how those servers are configured.
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Part Two — For the Choir Mixer Editor (continued)

Adding a Song


In admin mode, click the song title at the top of the player to open the song list. At the bottom of the list, you will see an Add Song option. Click it to open the Add Song dialog.

The Add Song dialog

The dialog has the following fields.

Song Title

The name of the piece, as it will appear in the song list. Songs are displayed in alphabetical order.

Sheet Music URL

Optional. Paste the URL of a PDF score here. When a singer clicks the sheet music link at the bottom of the player, this is what opens. Leave it blank if you do not have a score to link.

Number of Tracks

Choose how many vocal parts this song has — between 2 and 6. This sets how many track rows appear below.

Track rows

Each row has two fields: the name of the part (for example, Soprano or Lead), and the URL of the audio file for that part. Paste in the URLs you copied from the Media Library.

Track names appear on the track cards in the player. Choose names that singers will recognize from their sheet music.

When all fields are filled, click Create Song. The song appears in the list immediately and the configuration is saved automatically.

Editing a Song


In admin mode, open the song list and click the pencil icon next to any song to edit it. You can change the title, sheet music URL, number of tracks, track names, and audio URLs. Click Save Changes when done.

Renaming a song changes it everywhere — in the song list, in any playlists that contain it, and in the saved settings for singers who have listened to it. If you change the title, singers' volume and loop settings for that song will be reset, because those settings are indexed by the old title.

Deleting a Song


In admin mode, open the song list and click the trash icon next to the song you want to remove. A confirmation dialog will ask you to confirm before the song is deleted. The audio files themselves are not deleted — only the song's entry in the Choir Mixer configuration is removed.

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Part Two — For the Choir Mixer Editor (continued)

Phrase Markers


Phrase markers are labelled positions on the timeline that help singers navigate a song. A singer can press Tab to jump to the next marker, or double-click a marker to instantly loop that phrase. Well-placed markers turn a long recording into something a singer can move through efficiently.

Markers are per-song. You set them while that song is loaded in the player. Each marker has a time position and a label.

Adding a marker

In admin mode, play or navigate to the point in the song where you want to place a marker. Then do one of the following:

A.Click anywhere on the thin marker row just above the timeline. A dialog will open with the time pre-filled to where you clicked.
B.Hold Alt and click anywhere on the timeline itself. The same dialog opens at that position.

The dialog has two fields:

Time — shown in minutes, seconds, and tenths of a second (for example, 1:24.3). You can edit this field directly if you want a precise position.

Label — the name of the section, such as Verse 1, Chorus, Bridge A, or whatever naming your choir uses. This label appears on the marker triangle and in the score if singers are following along.

Press Enter or click Create to place the marker. It appears immediately on the timeline and the configuration is saved.

Moving a marker

In admin mode, drag any marker triangle left or right along the timeline. When you release it, the marker snaps to its new position and the configuration is saved automatically. Markers always stay sorted in time order regardless of where you drag them.

Editing a marker's label or time

In admin mode, double-click any marker triangle to open the edit dialog. Change the label or time as needed and click Save.

Deleting a marker

In admin mode, click the small ✕ that appears on a marker when you hover over it.

Placing markers well

The most useful markers are at the start of each major section — verse, chorus, bridge, coda — and at any phrase that singers commonly need to repeat. A song with four or five well-named markers is easier to navigate than one with twenty tightly spaced ones.

Listen to the song while placing markers. The most precise approach is to play the song, pause at the exact start of a section, and then click the marker row. The time field will be pre-filled to within a tenth of a second of where you paused.

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Part Two — For the Choir Mixer Editor (continued)

Exiting Admin Mode


Click the purple ⬡ Admin Mode — click to exit banner at the top of the player, or type ADMIN again. If all changes have been saved, the player returns to normal immediately. If there are unsaved changes — which should be rare, since most actions save automatically — you will be asked to save or discard them.

Troubleshooting


A song shows "Cannot reach file" when loading

The audio URL for one or more tracks is incorrect or the file is not publicly accessible. In admin mode, open the song and check that each audio URL is correct and returns the file directly when pasted into a browser. If you are using Google Drive or Dropbox, make sure the URL is a direct download link, not a sharing page.

Changes are not appearing after I save

Try reloading the Choir Mixer page. If the configuration was saved successfully, the updated songs and markers will appear after a reload. If problems persist, check whether the wp-content/uploads/choirmixer/ folder on your server is writable by WordPress.

I see "Auto-save failed" in the status bar

This means Choir Mixer could not write the configuration to your server. The most common causes are a file permissions problem on the uploads folder, or a session that has been open long enough for the security token to expire. Try reloading the page and entering admin mode again. If the problem persists, contact your site host to confirm that WordPress can write to wp-content/uploads/choirmixer/.

The sheet music link does not appear

Make sure the Sheet Music URL field in the song's settings contains a complete URL starting with https://. The link only appears when a valid URL is saved for the current song.

Choir Mixer is developed by Dave Kauffman.
For more information, visit choirmixer.ca.