Make a Morse code ringtone or alert sound
To make a Morse code ringtone, choose a short message, get it as an audio file at a speed and pitch you like, end it with a pause, and add it to your phone or Mac. The classic iPhone ringtone file is AAC audio ending in .m4r; the Mac’s built-in alert sounds are AIFF files, and you can add your own to the Sounds folder in your Library. macOS can make either file from your audio with a single command, so the hard part is choosing what your phone should say.
Choose a message that works as a sound
A ringtone is heard rather than read, and it repeats until you answer. The best messages are short and have a rhythm you can recognize across a room. A few that work well:
| Message | Morse | Units, with a word gap after | One pass at 15 WPM | At 20 WPM |
|---|---|---|---|---|
| HI | .... .. |
20 | 1.6 s | 1.2 s |
| SAM (a made-up name) | ... .- -- |
30 | 2.4 s | 1.8 s |
| CQ (calling any station) | -.-. --.- |
34 | 2.7 s | 2.0 s |
| 73 (best regards) | --... ...-- |
36 | 2.9 s | 2.2 s |
The units come from the standard timing: a dit is 1 unit, a dah 3, the gap inside a character 1, the gap between characters 3, and the gap after a word 7. At 15 WPM a unit lasts 80 ms; at 20 WPM, 60 ms. Count your own message the same way: H is four dits with three gaps between them, 7 units; I is 3 units; one 3-unit gap between them and a 7-unit pause after makes 20. Morse code timing: the 1, 3, 7 rule goes through the arithmetic.
Some choices that help:
- Your own initials, or a caller’s. Give one person their initials as a ringtone and you know who is calling before you look.
- A speed of 15 to 20 WPM. Much slower and the letters start to sound like separate beeps rather than rhythms. Much faster and only someone fluent will read it.
- A pitch you like in a mid range, somewhere around 600 to 800 Hz: easy to hear without being shrill. Choose by ear.
- Not SOS. It is the distress signal, sent as the single character
...---..., and a phone keying it in a quiet room can startle anyone nearby who reads Morse.
A text tone or alert plays once, so it should be one pass and short. A ringtone loops, so the silence at the end sets the gap between repeats. One word gap sounds rushed when it loops; a second or so of silence makes each pass a separate call.
Make the audio
There are three ways to get the file.
Generate it from text. A Morse app or tool that exports audio does the timing for you, and it is exact. In Dot & Dash on a Mac, type the message in Write and Send it to hear it on the machine, then share it as audio, which makes an .m4a file on your Mac. Save the message to the Library too if you might want it again later.
Build it in an audio editor. Many audio editors can generate a tone. Make one dit at your chosen pitch and length, copy it to make dahs three times as long, and lay them out with silences of 1, 3 and 7 units. It takes a while, but you will never forget the timing rule afterwards.
Record yourself. Key the message on a practice oscillator or any sidetone and record it. The ringtone then carries your own fist, unevenness included, which some people like more than a perfect machine.
Whichever route you take, play the result and check two things: that it reads correctly, and that there is enough silence at the end. An audio editor can add silence or trim the start if either needs it. More on all three routes in How to make a Morse code audio file.
Turn it into an iPhone ringtone
1. Keep it short. A few seconds per pass is plenty, and the whole file is best kept well under 30 seconds.
2. Try the iPhone’s own route first. Depending on its software version, the options for sharing or opening an audio file may include setting it as a ringtone. Move the file to your iPhone the way you usually move files, open it there, and look through its Share options. If yours offers that, use it, and you can skip the next step.
3. If not, make an .m4r. The classic ringtone file is ordinary AAC audio with an .m4r extension. macOS includes a command-line audio converter, afconvert, which can write one from common audio formats. In a command-line window, in the folder that holds your file:
afconvert -f m4af -d aac message.m4a message.m4r
If you already know your .m4a is AAC, renaming it to .m4r in Finder does the same job; Finder may ask you to confirm the new extension. How an .m4r gets from a Mac onto an iPhone has changed between macOS versions, and a method that worked on one may not work on the next, so check how it is done for the versions you have rather than relying on an old guide.
4. Choose it on the iPhone. Open Settings, Sounds & Haptics, then Ringtone, and pick it from the list. To give it to a single person instead, open their contact, tap Edit, then Ringtone.
Other phones usually let you pick an audio file from their ringtone setting, though the menus vary from one maker to the next.
Use it as your Mac’s alert sound
The alert sound is the one your Mac plays when something needs your attention, and you hear it many times a day, so keep it to a single character. R, .-., is a good choice: in radio shorthand it means “received”. At 20 WPM it lasts about 0.4 seconds. K, -.-, which means “over”, is another.
1. Convert to AIFF:
afconvert -f AIFF -d BEI16 message.m4a message.aiff
2. Put it in your Sounds folder. In Finder, choose Go, then Go to Folder, and enter ~/Library. If there is no folder called Sounds inside, make one. Copy the .aiff file into it.
3. Choose it. Open System Settings, then Sound, and look for your file in the Alert sound list under Sound Effects, alongside the built-in sounds. If it does not appear, quit and reopen System Settings.
Trim the file so it starts the moment the first dit starts. A gap of silence before the tone makes an alert feel late.
Questions
How long should a Morse ringtone be?
One pass of a few seconds is enough, because the phone repeats it while it rings. Keep the file well under 30 seconds, and leave a second or so of silence at the end so each repeat sounds separate.
What speed is best for a Morse ringtone?
Between about 15 and 20 WPM. That keeps each letter’s rhythm intact and is slow enough for anyone who reads Morse to follow.
Can other people read my ringtone?
Anyone who copies Morse at that speed can, so pick a message you are happy to announce in public. Initials or a short word like HI are safe choices.
Can I use the same file on the iPhone and the Mac?
Not always as it is. The classic iPhone ringtone is AAC audio in an .m4r file and AIFF is the safe choice for a Mac alert sound, but afconvert can make both from the same original.