Infinity Kappa 8's

I did the removal of the 12.5mH (but did not bypass the caps) mod last night on my Kappa 8's. My Rotel 1090 can go quite a bit higher now before going into protection and it runs cooler. I did not notice any significant changes in the bass response.

I plan to put in a SPCO switch that will provide normal mode, extended mode and allow the 12.5mH coil to be bypassed. This will let me compare the mod's sonics quickly rather than though the half our change over memory.

The stock Normal/Extended mode switch simply bypasses the 5 ohm, 50W resistor. It does not bypass the 12.5mH inductor which is always in circuit.

The previous owner of my Kappas did some work on the xovers and got ohms law wrong. He replaced the 5 ohm resistors and apparently couldn't find 50Wer's. He correctly put two 25Wer's in parallel to cover the 50 watts but incorrectly used 2.5 ohms think the value summed like the wattage. So the resistive value was 1.25 ohms rather than 5 which meant they were always running closer to extended mode. Explains why I didn't hear a difference and my amps still went into protection mode at the volume setting, regardless of the switch's setting.

Are these mods only for the kappa 8 or is it also beneficial with the kappa 8.1's?

I rand my 8.1's from a adcom gfa-5500.... Never a issue but not enough volume

Married a girl who had 5 parasound hca1500's (4 of which work) and tried a hca1500 in place of the adcom.... Much better everywhere. Then decided to bi amp the speakers and again a nice improvement. Each speaker gets 200-220w x 2..... But I have been debating on upgrading my amplifiers. Thinking of the wyredforsound sx1000 amp..... But I can't decide if it would be a improvement in sound going with a new class d amp..... And also being able to use Xlr inputs on the amp

Doing some house cleaning yesterday realized the foam surround on my kappa videos and kappa 5.1's is failing.... And suggestion on where to get new foam surrounds? Or but replacement speakers?

The Kappa 8.1's do not have the 12.5mH inductor and present a higher impedance load to the amp than the 8's.

I would keep the stock driver and just replace the surround. It's cheaper and you will maintain the designer's voicing and specs. There are bunch of folks that sell kits, with the foam glue and instructions...check eBay or goggle.

Hi All,

What do you all think about using more budget Class H and Class D amps....say Behringer Europower EP4000 and Crown XLS series?  I am using a EP4000 for my Kappa 7's and they sound excellent, maybe a little midrange 'breakup' or distortion at high volume, but really excellent control of the 7's.  The EP4000 however cannot handle my newly purchased Kappa 9's. 

Any suggestions of what amp might be a nice mid/high amp for the Kappa 9's in a bi-amped setup? I am looking for excellent holographic imaging and silky suite highs. ;-)

Also, I am confused as to how to split the signal coming from my pre amp for proper bi-amping.  Do I just buy a split balanced or RCA cable? Or do I use the additional outs on my preamp? My preamp is a Sonic Frontiers Line 2. Please let me know.

Thanks,
Brett

The speaker crossovers take care of filtering out the frequencies for the lows, mids and highs, so that is taken care of.
For pre-outs, if your preamp has multiple outputs, run 1 pair to your bass amp and the other pair to your mid/high amp. If it has a single output you can use a quality Y connector or cable to achieve the same result.

There is some interesting information in this discussion, glad I came across it.
I'm a long time Infinity owner since the late 70s, and have had Quantum 5s, Kappa 8s, Kappa 9s, IRS Deltas & IRS Betas as well as an assortment of center channel and bookshelf Infinity models.

I have had good results with Threshold S300, S300MK2, S350e, S500e and Hafler DH200, DH220 (stock and modified) amps, as well as a high powered class D amp from Class D Audio. With the Class D Audio amp, the Kappa 8s would trip the protection mode if pushed to too high a level though, but it does sound nice. Currently testing a pair of Doge Audio Tube mono amps, but have not tried them on 8s yet.

After reading some of the above posts, the 12.5 mH bypass sounds like a good idea, no matter what amp you end up using. A good approach might be to re-purpose the extended/normal switch, leave the circuit in either the default extended mode or optional normal mode, and then use the switch to remove/include the 12.5mH inductor from the circuit. That way you are not altering the cabinet in any way, and can restore the speaker back to factory configuration if desired. I am just in the process of selling a pair of Kappa 8s in Santos, and will recommend that the new owner perform that mod if he is open to it.