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
On the other hand if you find an Audio Research M300 you might be in heaven. Arnie has developed the Kappa 9's with that amp.
own kappa 9s run them with a bryston 4 nrb and bryston pre amp and 2 powered subs. Have the speakerers set on normal on back which reduces the low end while keeping everything else same. This makes the amp use less power making it more efficient. This is were the subs come in to pick up the lost bass. This made a HUGE difference. Have looked to trade in the kappas but havent found anything yet that sounds the same even at 3500+ but this is just my opinion what ever sounds good to you is the way you go.
I'm quite happy running my K9's with a pair of Threshold SA/2 monos. 100w/ch but plenty of current. I have run the speakers with a pair of Threshold S/500 II's in bi-amp mode as well and honestly the SA/2s sound way better.
I have to add that Mitch is right here.

if you do not biamply and put a Threshold S/1000 or SA/2 in front of them and use a good tube amp Audio Research SP11 or solid state Threshold FET 10e or 11 or SP15 this loudspeaker is going to blow you away!

They are real life keepers if you do not have the room for the RS-1, Gamma's or Betas.
Believe it, I bi-amped Kappa 9s with a pair of Sony TA-N80ES amplifiers together with a Sony TA-E80ES pre-amp for the last twenty years without any problem. I was in love with the Kappa 9s and decided to buy them even though the salesperson at the local high end electronics store has warned me they will destroy my Sony amps in few minutes. At first I was very careful with the volume level, then after playing the first album I cranked up the volume level and went through couple more albums without any problem, I was happy enough to call the salesperson and let him know my Sony amps could drive the Kappa 9s and also invited him over to my house and with my permission he cranked up volume to the highest level our ears could handle and by the look at his face, I knew he was shocked to see my Sony amps could happily run the Kappa 9s. Anyway, I highly recommend any Kappa 9s owners out there to look for a pair of Sony TA-N80ES amps on Ebay or Craiglist, and depend on condition might cost between $400 to $600 each.

Here's my email address if you have any questions about Sony amps: 7matchpoint@gmail.com

Specifications:

1. General
System: analog
Color: 1=Silver, 2=Black: 2 (Wood Sides)
Power consumption: 510 W @ 120/240 V

Power Amplifier
Speaker Outputs: 2 x 2 Speakers; Phones
Continuous Power 4Ω: 270 +270 (THD 0.006%)
230 + 230 (6Ω, THD 0.005%) Watts
Continuous power 8Ω: 200 + 200 (THD 0.004%)
1 x 610 (Mono) Watts
Frequency Response: 1-200,000 HZ
Input Sensitivity: 1,000 (balanced)
500 (balanced) mV
Input Impedance: 30 (unbalanced)
0.6 (balanced) kΩ
Harmonic Distortion: 0.004 (4Ω)
0.003 (6Ω)
0.0018 (8Ω) % at rated output

2. Physical
Dimensions in Inches: 18.50 x 7.28 x 17.32 (w) x (h) x (d)
Dimensions in mm: 470 x 185 x 440 (w) x (h) x (d)
Weight in lbs: 52.91 lbs
Weight in Kg: 24 Kg