My internet is super slow if I use my wireless router. I did a test with my internet provider and it's only slow when i use my hi-speed router.
What comparative speeds are you getting?
Is Airport/Wifi showing a strong signal?
What encryption is it using, & which exact Mac?
Open Network Utility in Applications>Utilities>Info tab, select Airport/Wifi & what is the Link Speed & are there any Errors/Collisions on the right?
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