I.G.
You don't need this! In fact you can sit down for a half an hour every day and read your unborn child a story or play him or her some music/sing songs. It will even be more effective, since it is YOUR voice and free, too.
In addition it will give you some time to bond with your baby and reflect on your emotions, expectations and hopes... kind of a meditation with your unborn child.
Congrats on the pregnancy and good luck.
PS: most "novelty" items for babies are either useless or can easily be replaced by something that is free. Some have even been shown to do more harm than good, when in doubt... you likely won't need it.