I can think of three other swords that proc song effects. Singing Short Sword (Bard Epic) procs Dance of the Blade that lasts a few minutes, Nature's Melody procs Song of the Deep Seas that lasts a few minutes, and Siren Song, Dagger of the Sea also procs Song of the Deep Seas that lasts 3 ticks (18 seconds) but will be buffed in a later patch to be a few minutes I believe.
Singing Short Sword procs Dance of the Blade -
10 : Increase Attack Speed by 55%
11 : Increase STR by 30
12 : Increase ATK by 30
http://wiki.project1999.com/Singing_Short_Sword
Siren Song, Dagger of the Sea and Nature's Melody proc Song of the Deep Seas -
9 : Increase AC by 15
10 : Increase STR by 30
11 : Increase AGI by 30
12 : Increase Attack Speed by 60%
http://wiki.project1999.com/Siren_So...ger_of_the_Sea
http://wiki.project1999.com/Nature%27s_Melody
All three weapons are rather difficult to get though.