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

For these speakers you need amps that give current with (Bi-Polar output stage) that can almost keep double their wattage down to 2ohms.

Look at the impedance graph and you'll see, it a pity there is no phase angle graph done on these as then combined with the impedance dips you may find even more horror scenario's.

http://emotivalounge.proboards.com/post/600160

Cheers George

I agree with George and again to tomlab.

The speaker was developed in conjunction with Audio Research M-300 amplfiers.
However Arnie used the SP-11 as a pre and various Threshold models to drive them full range.

For you info the Adcom wont do the job. The Kappas 9 impednace is below 1 ohm in the mid and highs and at the woofer region producing phase angels with minus 70 to 80 degrees. This is near a total short.

Therefore biamplfiying takes aout the stress produced by those angels.

I agree with micthforte that only very high current designs should be used and lower powered amps like the Adcom wont do it. The Parasound works quite well and if you have alow budget you might go for it, but do not expect that it will sound like Audio Nirvana.

For full range I would go with the big Threshold SA series and agood vaccum tube pre or an CJ Premier 5, Audio Research M-300, VTL Deluxe 300 or a McIntosh MC 275.

If your really low on bduget you can go with the Parasound I still would use a tube pre.

Should you ant to biamply you will need a Goldpoint stepped attenuator for matching the gains.

You can use the Prasound for the whole speaker, later use the Parasound for the bottom and apply a tube amp for the mid and highs. You need a seperate passive preamp for matching gains like the Goldpoint stepped attenuator.

Another soloution would be a Mark Levinson No.23 for just 2000$ bucks and use a tube pre like an Audio Research SP-6B or SP-8.


The Martin Logan CLSII does not produce difficuilt phase angels like the Kappa 9's and therefore they are much easier to drive.

I have experienced myself that a lot of money is necessary to keep the speaker work properly and if it is too expensive an Infinity RS2b has much lower requirements.

Hi
I ve had lots of amps on my k9's and all sound great. I'm running the kappa's with a musical fidelity a308cr power amp and that sounds very good. But even with a rotel 1080 it did a great job with no problem. 

Hello,
i bought some k9’s last year. I am running Phase Linear 400 on top and 700 on bottom.
I drove those speakers past concert levels but my power management system broke down taking my 700 with it. I use Signature AVS 2000 w/ HTPS Signature 7000. The 7000 failed reset itself and came back but I was left with a left channel out in the 700.
I sent the amp out and had it reworked to White Oak inwards. Fired it up and the Kappa’s sounded like they had subs inside of them. I know what subs do cause I got a spot in my house I call subcity and there are 3 subs over there.
I bought a C-19 and had it overhauled and modded by Carver repair west coast. Got another 7000 out of storage but overlooked the fact I didn’t grab a Signature and refired the system. Running about 10:30 I moved the gain up one spot right and turned the bass right channel max. I never made it to the left as the 700 main fuse died the 10amp one. Supply fuses still good. So been reading what you guys are saying and I’m not getting rid of the Kappa 9’s. Why? Where can I find speakers that sound like subs and have the satisfaction that I’m running amp killers. So I gotta order the fuses 10 amp and see how much damage has been done. And I’ve come to this conclusion, maybe I should get Audio Research M300 for bass side and move the 700 on top replacing the bullet proof 400.
I need to point one thing out the HTPS 7000 is rated out to 1440 watts which I exceeded that amount the night I blew it but didn’t know at that time. I never heard you guys talk about Phase Linear amps on this thread but mine had to push past 1440 that night to kill the 7000. Which will find its way back to Monster.
So what say all of you since I’m not selling?
One thing I left out went from 10:30 to 11:30 but the night I blew the 7000 I was out past 2pm.
I said I’d never run that hard but geez the Kappa’s make me do it.
i got gobs of will power but the Kappa’s say turn the knob...