There's a perfect solution to your budget and hunt for quality.
I purchased the
Swan M10s after reading all over the internet about them. They're literally the 'sleeper' of desktop speakers. I ordered a set on Tuesday this week.. looking for them to arrive tomorrow or Monday at latest.
The only downside is.. the sub must be placed on the desk (because it's directional.. for best results). But you honestly cannot beat the Swans in their price range. If you google the Swan M10s, you'll find a huge wealth of information on audiophile forums all over the internet.
If you are looking for a sub to blow tiles off of your roof, then go for the Logitechs/Klipsch/Bose. The Swans triumph in sound and build quality (and they are cheaper too.. came out to $124 shipped).
They're pearl white/black housing with golden cones and gloss black tweeters. They will look beautiful with your mac.
Hope this helps. I'll try to get a few set-up shots posted when it arrives

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