what kind of external speakers to get

i am about to purchase a messenger, what do i need to hook up speakers? looking at JBL under 400 for pr. what else do i need to get started? over ear headphones , can i use my apple airmax?

You can use the airmax if you have the add on cable to plug into the headphone out. I think that cable is also 1/8" jack so you would need a 1/8" to 1/4" adapter as well

Don’t know what you mean by the JBL speakers. If they are just passive speakers you would need a power amp of some sort to drive them. If they are powered speakers you would be fine.