Help power pair of Infinity Kappa 9's please


Hi all!
I have a pair of Infinity Kappa 9's:
Nominal Impedance: 4 to 6 ohm
Power Rating: 60-340 watts RMS
Efficiency: 102 dB SPL @1 watt, 1 meter
Crossover Frequencies: 80Hz, 800Hz, 4500Hz
Frequency Response: 29Hz-45kHz +/-3dB
Physical Attributes:
1x - SEMIT Supertweeter
1x - EMIT Tweeter
1x - 3" Edgewound Voice Coil Polydome Midrange Driver
1x - 5" Polypropylene/graphite Diaphram Polygraph
2x - 12" Cast Frame , L/C Tuned Woofers
Dimensions: 59.5"H x 21.5"W" x 8"D

My room is 12'x12', I have $2500 budget and would like to play music off my computer. I need amp(s), a preamp, and a DAC i guess (is the DAC necessary at my low of a budget range?). I know my budget is low so I will be shopping for very used/old equipment. If anyone has any experience, suggestions, or words of wisdom, they would be very much so appreciated.
Thanks,
JT
jtiesel2
This speaker is way too big for your room. There is an error in your specs. The efficiency is not 102db. It is more like 88db, but the Kappa 9 has a volume threshold and refuses to play loud with most amplifiers. Besides that it is a difficult load for amplifiers. Your budget of $2500 will most likely be spent on a used Krell or Levinson amplifier in an effort to drive your Kappa 9 speakers properly.

If you like Infinity speakers I recommend you sell the Kappa 9 and buy a much smaller Infinity speaker more suited to the size of your room and less finicky about electronics and you will have much better sound.
The room opens up to the rest of the house, we party loud, very loud. If I could sell the Kappa 9's for let's say $2000 what speakers, in that price range, would have "much better sound"? Also the efficiency rating I posted is directly out of the owners manual:
http://www.infinity-classics.de/infinity/technik/manuals/Kappa_9_technical_sheet.pdf
I should have acknowledged that the room is not ideal for the speakers. But letting them go is not really an option for me, because in my opinion there is no better sound for the money. I appreciate your input, I will look into some Krells and Levinsons.
Agree with above post,those speakers are amp-killers.Anything besides a high current amp will melt.2500$ will barely find one worthwhile.Good luck,Bob