Sending pulses to a 1531 strobotac stroboscope with external trigger

Hey I'm an artist working and know little about physical computing and arduino for that matter. I'm not completely oblivious since I do do a lot of research but I don't know how to proceed with this one so I'm asking for your help please.

I want to control the 1531 strobotac from it's external trigger. It takes a quarter inch phono jack. I need to trigger the strobes inbetween a threshold of about 59-61 hz per sec. I want to be able to control the value in Hz with an EEG device. I was told that maybe I need to get a relay switch because the Arduino may not be fast enough? Can anyone confirm this? I've attached a youtube link on this guy discussing the external trigger and the data sheet for the 1531 strobotac. Please help this assignment is due on tuesday!