I've been playing with espeak tts, and I found this wonderful tutorial for how to improve the voice quality:

http://linuxsake.tumblr.com/post/276...e-sound-better

However, when I try to run
espeak “Hello robots” —stdout | play -
I get the following error:
play FAIL formats: can't determine type of `-'

Does anybody have any idea for why this might happen? I'm pretty new to sox and Linux audio in general.

If it make a difference, I'm running raspbian on a Raspberry Pi, using PulseAudio.

Be careful when copying commands directly from the net. The "—" in the above is an em dash, not the ascii hyphen the command needs.

1 members found this post helpful.

Awesome, I had never heard of that before. How do I type that on my keyboard/copy it correctly?
I copied it from midori, which might copy differently than other browsers.

After pasting it you'll have to go in and manually correct it, of course. Shell syntax only needs the standard ascii characters produced by the basic keyboard keys.

Also be on the lookout for the less common EN DASH (–) and "smart" quotation marks (“”|‘’), among others. Word processing software will often convert the ascii characters into the fancier literary versions.

http://en.wikipedia.org/wiki/Dash
http://en.wikipedia.org/wiki/Quotation_mark
...etc...

If you want to actually produce fancy characters like these you can use the same multi-key input system used for fancy characters in other languages. The combination "<multi><minus><minus><minus>" produces the em dash, for example. Your "/usr/share/X11/locale/en_US.UTF-8/Compose" file will contain the definitions of all the characters it can produce. It's a long file. Change the locale to the one you use if it isn't English.

There are also character selection tools and input methods available, but the multi-key is the most convenient. Look it up.