我的终端为何没有铃响？

[罗非鱼]

有一个教程：http://unix-cd.com/vc/www/39/2007-06/2409.html
# echo -e "\007your home is $HOME , you are connected on `tty`"
这个命令的执行结果是：
1、输出
# echo -e "\ayour home is $HOME , you are connected on `tty`"
your home is /root , you are connected on /dev/pts/1
2.终端铃响一声
我看见结果1，为何没有结果2？

[tusooa]

貌似是很老的写法了。