Happy Birthday is NOT a Public Domain song. It's actually still in copyright, that's why you rarely hear it on TV or the movies.
Smartsound is a very good option, but you missed the big $29/album sale, they have them 2-3 times a year.
HP Envy Phoenix/4thGen i7-4770(4@3.4GHz~turbo>3.9)
Nvidia GTX 960(4GB)/16GB DDR3/
Canon Vixia HV30/HF-M40/HF-M41/HF-G20/Olympus E-PL5.
Tape capture using 6 VCR, TBC-1000, Elite BVP4+, Sony D8 camcorder with TBC.
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