Question

What is "Hoenn Sound"??

Comments

Oh, jeez, I can see why this was edited, the old title was "A question about Pokemon....?"
No offense XX-Ohsawott-xX, but if it wasn't a Pokémon question, you'd be in trouble.

Answer 1

After you get the national Pokedex Hoenn Sound plays on the Radio on Wednesdays.

In Union Cave, make sure the Hoenn Sound music is playing and then find a Pokemon. If not Makuhita, rinse and repeat.

Source: http://bulbapedia.bulbagarden.net/wiki/Pokémon_Music_Channel and personal experience.