To have the system make an audible bell alert in Ruby use puts "\a" or puts 7.chr e.g.

To test the bell is audible on your system first try the following command from the shell

echo -en '\007'

If that test was successful then open an IRB session and try the following:

puts 7.chr

# or

puts "\a"

# or

puts ("%03d" % "0x07").to_i.chr


Resources:
- linux shell: making the shell alert or beep [dzone.com]
- Ruby Strings [tutorialspoint.com]

Read more: http://feeds.dzone.com/~r/dzone/snippets/~3/Fs_okESKdl8/11191