#4 is a musician's ear plug , attenuates the level, but doesn't entirely block it.
Like an industrial hearing protection ear plug should.

You want to hear your tunes ? an in ear stage monitor may suit

http://pro-audio.musiciansfriend.com/product?sku=H72276

or cheaper
http://pro-audio.musiciansfriend.com...uds?sku=500976

though not hearing rear approaching traffic may not be the best.