E♭ alto · concert pitch
Slide the harmonic shelves
Each row is one harmonic partial; each column extends the slide by one approximate semitone. Tap any pitch to move the real seven-position geometry and hear it.
E♭4
Center: 4th partial is acoustically centered.
The following is an interactive chart that lets you play sounds that maps pitches to slide positions for the E flat alto trombone. To use this, either click on the grid using your mouse or press keys on your computer keyboard, which will move the virtual slide around the graph and sound a note as well as travel up and down the harmonic series. It’s a great way to learn about the physical workings of the instrument while also developing your sense of partial relationships and intonation.
Notes is laid out across the main grid, with each row representing harmonic partials and each column representing slide positions. To see a particular pitch, simply click the relevant cell and the animated trombone slide will jump into place while the highlighted note plays. On the left hand side is a large display area that shows the note name, its frequency, position and partial number. A tiny number shows the current position (1-7) of the trombone’s standard set of positions.
How to Use the Trombone Chart
The band selector buttons allows you to show just the upper partials (five through eight), lower ones (two through four) or all of them at once. This allows you to narrow down what you’re seeing and concentrate on a particular register without extra notes getting in your way.
The volume slider lets you adjust how loudly you want the sound made by the app to be with a view to keeping it comfortabley under way in your space.
To play notes on the keyboard, tab into the grid to select any note. Then use the up/down arrow keys to select different partials and the left/right arrow keys to navigate between two slide positions. Sound the selected note by pressing the enter key or space bar. That way, you can be more accurate when navigating around a piece since you are not using a mouse. You can easily work out how to make quick changes of position or learn how certain intervals sounds.
Another interesting feature is the glide button. It gives you a preview of what you will hear when you operate the slide by playing through all seven positions of your chosen partial, one after the other. This illustrates the gradual increase/decrease of the pitch of the note and therefore the lengthening/shrinking of the slide without any discrete jump. This is a helpful addition to the experience of grasping the acoustical distances between positions on a given harmonic shelf.
Below the picture of the instrument are some intonation hints that guide you towards getting it right. As you may know, brass instruments has a natural tendency to be flat or sharp according to which partial they produce. The chart depicts this naturaly acoustics reality. If a partial is centered, high, or low, you’ll read the text underneath with a small adjustment of the slide suggested. Exact sound feedback is provided by the tiny cent value in the corner of each cell as you learn to train your ears. To see how much a small slide movement change the pitch, try using the same note in a neighboring position on the same partial. Switching up and down from the lower to upper shelf you can hear the difference that it makes to the spacing across both registers.
The fullscreen mode (useful if you have a small screen) increases the size of the chart so you can see more easily. Spend some time exploring this grid and listening to the results. You should of spend time exploring this grid and listening to the results.