DropEXP: A Deep Exploration of Drop Voicings on String Instruments

The app is extremely intuitive, especially if you have the theoretical knowledge of the drop voicings’ construction, although this knowledge is not required to take benefits of the app. 

Here is a list of the functionalities. Screenshot comes from the desktop version, so yours may look different if you’re using a mobile device. 

The screen is divided into 10 sections:

1- The fretboard. Pretty standard, high string on the top, low string on the bottom, you also have the fret numbers below and the tuning notes for each string on the left. Fretboard’s features are:

• The voicing’s current top-note string is highlighted.
• Click on the voicing’s dots to hear each note individually.
• Use the left/right arrow keys (top-right corner above the fretboard or keyboard shortcuts) to move through voicing’s inversions, by moving the top-note up or down, keeping it on the same string.
• Use the up/down arrow keys (top-left corner above the fretboard or keyboard shortcuts) to move the voicing’s top-note string up and down.
• When several chord shapes are available for one voicing, the Alt button (bottom-right corner under the fretboard or ‘s’ keyboard shortcut) allows you to move through the different chord shapes.
• Use the 10 buttons above the fretboard to select the drop family to display. ‘D2’ is for Drop 2, ‘D2&4’ is for Drop 2&4, ‘DD2’ is for Double Drop 2 etc..

2- The tonic selector. Straightforward: Select the tonic of the main chord you want to work with. You select the note name and the alteration separetely.

3- The chord quality selector. Use the 2 drop-down menus to select the quality of the main chord. The qualities are organised in families (left menu) so you can easily find what you’re looking for. All possible 4-note sets (165 in total) are available with the premium access, which you can get by making a donation to the project. With the free version, the access is limited to the ‘Basic 7th Chords’, which is already a lot of work to master and to have fun with!

4- The main chord symbol. Here is displayed the chord symbol for the set selected in the chord quality selector, whenever it can be interpreted as a chord. Otherwise, the name of the set quality is displayed, like with tetrachords for instance. Below the chord symbol you can access 2 modifiers:

• The root modifier allows you to transform the root of the chord into a ninth (natural, flat or sharp).
• The fifth modifier allows the transformation of the fifth into an eleventh (natural or sharp) or a thirteenth (natural or flat). This modifier works only with sets that contain a perfect fifth.

5- The staff. Nothing special here: the current voicing displayed in standard notation, using the eventual transposition of the selected instrument. For example, guitar sounds one octave lower than written.

6- The secondary tonics panel. To me, this is the most powerful feature of the app. Whenever you select a chord quality, the app analyzes it against all notes of the chromatic scale as a tonic, and displays the corresponding chord symbol. Clicking on a specific tonic will modify the drone and bass notes of the playback, taking the ear-training capabilities of the app to the next level. Below the panel, you’ll find 2 buttons that will decide how the voicing analysis is done:

• Tonal. Only regular chord symbols with available extensions in tonal music will be displayed.
• Chromatic. Uncommon chord symbols with chromatic extensions will be included. Only for the braves!

7- The playback controls. Press one of the five staff icon buttons to hear the voicing. Playback’s mode for each button is: block, roll-up, roll-down, arpeggio-up, arpeggio-down. Below the playback buttons, you can control 3 more features:

• The sine wave icon button switches on and off a tonic drone based on the secondary tonic. Very useful to develop rootless voicing hearing.
• The bass clef icon button activates a bass note playing before the voicing to reinforce your rootless voicing ear-training.
• The auto-play icon button switches on and off the automatic voicing playback on any voicing inversion change. Cool!

8- The fretboard parameters. Here you can fine-tune your fretboard:

• The drop-down menu gives you access to a lot of different guitar tunings, including guitars with more than 6 strings, as well as a bunch of string instruments: the E-bass, mandolin and string quartet families are all here.
• Rootmap. Displays the main tonic all over the fretboard as a reference. Useful to memorize rootless voicings location.
• Hand. Switches the fretboard for left-handed people.
• ABC. Select how the voicing’s dots are labeled. You have 3 options: standard english names, latin solfege names or degree’s analysis. Be careful, the latest are calculated using the secondary tonic panel, not the main tonic.
• B&W. Switches between monochrome or color-coded dots.
• Spread stepper. Defines the maximum spread for the voicings in fret. Allows you to sort out large chord shapes that may be too big for your left hand.

9- Links. Various links, including to: the MusicInBrowser’s menu, my website, the app’s user manual, various social medias (youtube, facebook, instagram). Also one button to switch into fullscreen mode, and another one to display a keyboard shortcuts reminder.

10- Login & Donate. If you’re not a donor yet and enjoy using the app, please consider becoming one by clicking the Donate button. All the donors have access to premium content and to the discord channel. If you already are a member of this nice community, you can login here to access premium content. The login page opens in a new window that you can close once you’re logged in.

Keyboard Shortcuts.

I really designed this app to be used with a computer keyboard… learn keyboard shortcuts and speed up your learning flow!

[0-9] Drop setting

right arrow Next inversion
left arrow Previous inversion
down arrow Next top-string
up arrow Previous top-string

s Alternate shape

[a-g] Root selection

– Flat Root
= Natural Root
+ Sharp Root

] Next bass Note
[ Previous bass Note

ctrl d Toggle Start/Stop drone
ctrl b Toggle On/Off bass
ctrl a Toggle On/Off autoplay
ctrl c Toggle Dot Color/Monochrome

r Toggle Show/Hide RootMap
h Toggle Right/Left-handed
l Toggle Dot Labelling

> Increase shape spread
< Decrease shape spread

k Toggle Show/Hide keyboard shortcuts

Please feel free to write any remark in the comment section below. Follow me and the MusicInBrowser project on social medias and if you find it useful… spread the word!

Thanks for reading.

Version history

• 2025-12-07 – v2.01 [beta]

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