Ircle is the leading IRC chat client available for Macintosh. Ircle is very robust in features. The entire application is scriptable via AppleScript - which makes the functional possibilities endless, and makes products such as IRCmagic possible. You can download Ircle from The Official Ircle Homepage.
IRCmagic uses AppleScript to do it's magic. Information on AppleScript can be found at Apple's AppleScript Website.
IRCmagic currently supports SoundJam, SoundApp, and Audion as media players. Media players must support AppleScript to be compatible with IRCmagic. At the very least a player must support the open AppleEvent for playing sound files. If your favorite media player is not scriptable, write the author requesting that scriptability be added to it. Other media players may or may not work with IRCmagic. If you would like me to support your favorite media player, and I will take a look at it.