This guide describes Choir Mixer, a tool for learning choral music by ear. It is written for choir members — people who sing, not people who program computers. You do not need any technical background to use Choir Mixer, and this guide assumes you have none.
The guide describes what Choir Mixer does, how to use it, and what to expect. It is organized so that you can read it from beginning to end the first time, and return to any section later as a reference.
Choir Mixer plays the audio tracks for a choral piece. Unlike a simple audio player, it plays each vocal part on a separate track, and lets you adjust the volume of each part independently. You can turn your own part up while turning the others down, or mute everything except the part you are trying to learn.
Choir Mixer also lets you slow the music down without changing the pitch. At 75% speed, a piece plays more slowly, but the voices still sound like voices — not like a record running too slow. This makes it easier to learn passages that move quickly.
Finally, Choir Mixer lets you loop a section of the music — to play a phrase over and over until it is familiar, without having to rewind manually each time.
Every setting you make is saved automatically in your browser and restored the next time you open the page. Your settings are yours alone — no one else sees them.
When you open Choir Mixer, you see a dark window with several areas. From top to bottom, they are the song title, the track cards, and the transport controls. Each is described in its own section below.
The name of the current song appears at the top of the window, in the center. Tap or click it to see a list of available songs and choose a different one. The mixer reloads with the correct tracks and any markers or loop settings you previously saved for that song.
Below the song title is a row of cards, one for each vocal part — Soprano, Alto, Tenor, Bass, or whatever parts your choir uses.
Drag the volume slider on any card to raise or lower the volume of that part. The other parts are not affected. Your setting is saved automatically and restored when you return to the song.
The pan slider positions that voice in the stereo field, between left and right. The default positions are spread automatically to make the parts easy to distinguish in headphones. Pan settings are saved along with volume.
Click the Mute button to silence a track completely. Click it again to restore. When muted, the card is visually dimmed. Mute does not affect the volume slider position — your carefully adjusted level is preserved and restored the moment you unmute.
Solo has two modes. Press and hold the Solo button to hear only that part for as long as you hold — a push-to-hear control useful for a quick check. Release to restore all other tracks immediately.
For extended listening, hold the Solo button for three seconds. It latches on, silencing all other parts until you click it again to release. Latched solo is useful when you want to listen to a single voice for several phrases without holding the button.
Below the track cards is a row of controls for playing and navigating the music.
The Play button starts playback from the current position. While the music is playing, the same button becomes Pause. You can also press the Space bar on your keyboard from anywhere on the page.
A bar below the transport controls shows the full length of the song. A moving line within it shows the current playback position, with elapsed time on the left and time remaining on the right. Click anywhere on the timeline to jump to that point, or drag the line to move through the song.
The Speed slider slows playback from 100% down to 25%, preserving the original pitch. Drag the slider to the left to slow the music down. When the speed is not 100%, Choir Mixer recalculates the audio, which takes a moment. The slider turns amber while processing and green once the new speed is active. Playback resumes automatically from where you were.
The Pitch control shifts all the parts up or down by semitones — from three semitones down to three semitones up — without affecting the tempo. Pitch and speed can be combined freely, and both are applied in a single pass.
The Loop button turns looping on and off. When looping is on, the music plays between two handles — the loop start and loop end — and returns to the beginning of that region when it reaches the end, repeating indefinitely. You can also press L on your keyboard to toggle loop mode without touching the mouse.
Your choir administrator may place phrase markers at significant points in a song — the beginning of a verse, a chorus, a bridge, or any section that singers are likely to return to. Markers appear as small downward triangles on the timeline.
Single-click a marker to jump the playhead to that position. Double-click a marker to set the loop region from that marker to the next one and enable loop mode automatically — a quick way to isolate a specific section for practice.
Press Tab to jump the playhead to the next marker. Press Shift-Tab to jump to the previous one. Each press moves cleanly to the beginning of the next or previous section, so you can move through the song by musical phrase rather than by time.
If the playhead is within half a second after a marker, Shift-Tab skips that marker and goes to the one before it.
When looping is on, Tab and Shift-Tab navigate only within the loop region.
| Space | Plays or pauses. |
| L | Toggles loop mode on or off. |
| Tab | Jumps to the next phrase marker. |
| Shift-Tab | Jumps to the previous phrase marker. |
| Right arrow | Moves the playhead forward by ten seconds. |
| Shift-Right | Moves the playhead forward by thirty seconds. |
| Left arrow | Moves the playhead back by ten seconds. |
| Shift-Left | Moves the playhead back by thirty seconds. |
Keyboard shortcuts work from anywhere on the page except when a text field is focused.
To practice a specific passage, you set a loop around it.
First, turn on looping by clicking the Loop button. A pair of triangular handles appears at either end of the timeline, spanning the full length of the song.
Next, drag the left handle — the loop start — to where you want the passage to begin. When you release it, the right handle — the loop end — moves to a position a short distance later, giving you a working region to start with.
Drag the right handle to where you want the passage to end. The out-point moves freely without snapping.
You can also double-click any phrase marker on the timeline to instantly set the loop from that marker to the next one.
Press Play. The music plays from the loop start, and when it reaches the loop end, it returns to the start and plays again. Press the Loop button to turn looping off; the music continues playing from the current position.
Drag the loop start handle to the right while the music is playing — you will hear audio from the new position in real time, so you can find the right entry point by ear. Drag it to the left and the audio pauses momentarily until you settle on a position, then resumes. This lets you audition the in-point without stopping and restarting.
When you stop playback while in loop mode, the playhead returns to the loop start so you are always ready to resume from the beginning of the section.
If your choir is preparing several pieces at once, you can group them into a playlist and move through them in order without selecting each song manually.
Tap or click the song title to open the song list. At the bottom of the list you will find a Playlists section. Click the plus button to create a new playlist and give it a name — for example, Sunday's Rehearsal or Spring Concert.
Once the playlist is created, add songs to it by selecting them from the song list. You can add songs in any order and rearrange them afterward by dragging.
Select the playlist from the song list to begin. Choir Mixer loads the first song and plays it. When the song ends, Choir Mixer advances automatically to the next song in the playlist.
Playlists are saved in your browser and will still be there the next time you open Choir Mixer. They are stored on your device, not on the server, so they are private to you.
The mixer saves the following between sessions, stored in your browser:
Your volume and pan settings for each part, per song. Your loop start and end positions, per song. Which song you were last listening to. Your playlists.
The following reset each time you open the page or switch songs: whether loop mode was on or off, the speed setting (always returns to 100%), the pitch setting (always returns to the original), and which tracks were muted.
Press and hold the Solo button on your card to hear your part alone, then release to hear how it sits in the full mix. For extended listening, hold the button for three seconds to latch it on — the other parts stay silent until you click the button again. Use Mute to silence specific parts that are distracting while you focus on your own line, without losing your carefully set volume levels.
Double-click the marker at the start of a difficult section to instantly loop between that marker and the next. Reduce the speed to 75% or lower, then press Play. The passage will repeat continuously at the slower tempo. Gradually increase the speed as your confidence grows.
If the song sits a little high or low for your voice, try shifting the pitch by one semitone in either direction. You can combine a pitch shift with a speed reduction; both are applied in a single pass with no extra wait.
Click somewhere on the timeline to place the playhead roughly where you want the loop to begin, then press Tab or Shift-Tab to step to the nearest phrase marker. Once the playhead is where you want it, drag the loop start handle to that position. The handle snaps to nearby markers as you drag, so landing on a section boundary is easy.
With the music playing in loop mode, drag the loop start handle slowly to the right. You will hear audio from the new position in real time. When you hear the phrase you want to start from, release the handle. This lets you choose your in-point by ear rather than by guessing at a position on the timeline.
If you find the embedded player too small for comfortable use — particularly when working with the timeline or loop handles — click the small expand icon (⤢) in the upper right corner. Choir Mixer opens in a full browser tab at full size, with the same song and settings. The larger view makes it easier to place the loop handles precisely.
If sheet music has been linked for the current song, a link appears near the bottom of the window. Tap it to open the PDF in a new tab. You can then listen in Choir Mixer while reading from the score in the adjacent tab.