Bookshelf speakers + amp as computer speakers <$400

So you're asking about active speakers, like studio monitors with built in amps? The emotiva airmotiv 5 are on sale for $399 a pair right now. the audiengine a5 you mentioned are also recommended a lot.
http://emotivapro.com/products/powered_monitors/

Another option would be to use a cheap t-amp to power regular passive bookshelf speakers. I've used the dayton dta-100a amplifier and psb image b5 bookshelves and they worked fine with my pc. The dayton build quality is a little janky but it's the only amp I know of like that other than the ultra cheap lepai tripath amps which are lower power and even worse built.
the dta 100a is $99 from parts express, then you could spend the rest on speakers.. here's a couple of options
http://www.ascendacoustics.com/pages/products/speakers/cbm170/cbm170.html
http://www.theaudioinsider.com/product_info.php?products_id=65

The problem is that to do justice to a good $300 pair of speakers you will need to spend $500 or so on a an amplifier, for example the NAD C326BEE or the Music Hall A15.2.

I DO have a NAD C325BEE advertised in the classifieds here for only $225, however (like new), that would solve that problem. Put it with the S30 speakers and you would be good to go. Shipping to Canada is a problem, though, isn't it?

Or you could get the Audioengine 2 speakers for $200, and a small subwoofer for $100-200 to use with them. That is exactly what I have with my desktop PC and it is good. The amplifiers in those sound fine.

oh I see.. so you have $400 budgeted for speakers alone without a receiver?
These are good Focal Chorus 705v http://www.dedicatedaudio.com/inc/sdetail/34397 $399 on sale

IMO the Audioengine 2 speakers sound better than ANY speakers would with that amplifier; the sound of that amplifier does not impress me at all.

I suggest that you read the review Stereophile did on the Audioengine 2 speakers.

You don't need an external amp for most of the bookshelves in that price range. An AVR will work fine (I'm running mine off an old Sony).

I'd look first and foremost at the pro-style monitors. They are made for exactly this sort of listening setup (nearfield). The Behringer 2030 is an excellent speaker that will set you back about $200 a pair. It's major competition is easy to spot (Hit a Guitar Center, or the instrument section of your local BB, etc)

I use a pair of PSB 400i's that I got off Craigslist. They were about $400 a pair back in the 90s when they were new. They stood out for me in practice because of very good off-axis response on the vertical access (I've put $1600/pr speakers there and it was not as good). I've heard PSB mentioned in similar threads, so perhaps this nearfield response is a trait that persists in their modern bookshelves.

Destroy? What is it you want them to do? Get loud? Have good sound quality?

If sound quality is what you're after and that budget is firm, get the Dayton DTA-100a (see uncola's post above) or an Audiosource Amp-100 and spend the rest on the speakers.

http://www.parts-express.com/pe/showdetl.cfm?partnumber=300-383
http://www.amazon.com/AudioSource-AMP-100-Stereo-Power-Amplifier/dp/B00026BQJ6

The Mini-X is nice, and something you can use for years to come, as long as you have space for it and can find another $300 or so for speakers. It could be something you'd enjoy owning more so than the above, if having cool gear matters.

Or a used amp / avr if you run across one and have space.
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Edited by buzzy_ - 12/29/12 at 5:33pm