Can WiFi Bro Printer Connect To Airport (iMac, 10.4.11) Without Router

OK, for someone whose been using Macs since the mid 90's, this should be a no-brainer, guess I'm getting old... have a Brother MFC-490CW all-in-one and want to connect it to my iMac 20" 2GHz Intel Core Duo 2G 667MHz SDRAM(Early'06)... have had it USB for a few years now, decent printer, but I now have a brand new 27" iMac Intel Quad-Core i7 2.93GHz 1333 MHz, 12GB RAM, 1TB HD. A true beast, at least for iMacs. I got tired of waiting for my grandkids' family movies to render in iMovie and iDvd, plus am buying better video recording cameras. Want to connect the printer to my 2006 model iMac (printer has working 802.11g and iMac has Airport Extreme built in (0x14E4, 0x89)... since I've heard of problems going through wireless routers, (I internet through both ethernet cables and a Linksys WRT160Nv2 router)... the issue sometimes is that if you mix your wireless router signals (n,b,g) it can slow down your n transfers... anyway, I can't seem to do an ad hoc connect from printer directly to my internal Airport card... is it necessary (I know it's possible) to go through my wireless router? Any help will be greatly appreciated, and hopefully I can be helpful to some of you, having used so many different apps over the years... Thanks, Dan