Time to produce a sound file: < 1 Minute (with a bit of routine)

If you have an Apple Mac and want to create your own quality voice sound files using macOS Siri voices – read on…

There is an existing, vast downloadable collection of OpenTX sound files called “OpenTX Soundpack Joanne“, which might be more than enough for most of us. But if you have specific tracks to record, it is fast and easy to do it yourself as described here below.

For sound files to run on OpenTX 2.2.x or later, the following official OpenTX specs apply – this is just FYI:

  1. File Name: 123456.wav (up to 6 characters plus .wav)
  2. Sample Rate: 32 kHz
  3. Bits / Sample: 16
  4. Tracks: 1, mono
  5. Compression Codec: PCM (or u-law, a-law)

Don’t be put off by the technicality of those specs above. We will use a conversion website that will take care of all that. I have no idea, what exactly those specs mean neither.

First Step: Let’s have Siri produce the voice file

  • Open the Terminal application on your mac (CMD + space, type terminal)
  • in Terminal type cd desktop, to make sure the sound files produced will be saved on your computer’s desktop.
  • To produce a file with the name “a2roff” containing the sentence “ail to rudder, off” paste
    say -o “a2roff” “ail to rudder, off”
    into the terminal application. Paste the whole line including the quotation marks, press enter and the voice file is created. It takes no time. You won’t get any confirmation that the file was created. It’s just done. Check your desktop. The file will be called a2roff.aiff. We will convert the file to the OpenTX specifications in the second step.
  • You obviously can replace the file name and the sentence you want Siri to say to whatever you like. If you add a “,” (comma) in the text, it will create a slight delay between the words.

Second Step: Convert the .aiff file to .wav using the correct specs

  • Done. Place this newly created sound file in the usual directory on your TX sd-card (E.g. SOUNDS/en/).

This is the ail to rudder, off wav file spoken by Siri:

Side Note

To keep a record of the sound files created and to speed up the process, I use an Excel sheet that puts together the line to paste based on my entry of file name and text I want Siri to speak. If interested, give me a shout. I am happy to share it. It looks like this:

If you want to create the Excel file yourself, the only tricky line is in column E, the formula is:     =B9&” “””&C9&””””&” “””&D9&””””   and combines the info in columns B, C and D. All you need to do is to copy the line in Column E into Terminal.