Introducing the espeak-ruby gem

require 'espeak'

include ESpeak

# Speaks "YO!"
speech = Speech.new("YO!")
speech.speak # invokes espeak

# Creates hello-de.mp3 file
speech = Speech.new("Hallo Welt", voice: "de")
speech.save("hello-de.mp3") # invokes espeak + lame

# Lists voices
Voice.all.map { |v| v.language } # ["af", "bs", "ca", "cs", "cy", "da", "de", "el", "en", "en-sc", "en-uk", "en-uk-north", "en-uk-rp", "en-uk-wmids", "en-us", "en-wi", "eo", "es", "es-la", "fi", "fr", "fr-be", "grc", "hi", "hr", "hu", "hy", "hy", "id", "is", "it", "jbo", "ka", "kn", "ku", "la", "lv", "mk", "ml", "nci", "nl", "no", "pap", "pl", "pt", "pt-pt", "ro", "ru", "sk", "sq", "sr", "sv", "sw", "ta", "tr", "vi", "zh", "zh-yue"]

# Find particular voice 
Voice.find_by_language('en') #<ESpeak::Voice:0x007fe1d3806be8 @language="en", @name="default", @gender="M", @file="default">