Infinity Kappa 9's sound terrible...HELP

Recently I got a pair of Kappa 8's. Plugged them into Adcom 860 preamp and to an old HK Citation 16, GFA-555 and GFA-565's. They sounded...beyond my wildest dreams! Absolutely amazing!

A week later I bought a pair of Kappa 9's. Was really excited thinking they would out preform the k-8's! Plugged them into the same system and they sounded like crap. Tried running each k-9 to 1 GFA-565 and bi-wire them, changed all knobs to flat, experimented with the adjustments on the back of the k-9's in every conceivable position, ran them in standard and extended bass modes...and they still sounded terrible!

Has anyone experienced this before? Any tests or checks I can do to eliminate any doubts of anything? If I can't resolve this on my own, I guess I'll have to take the speakers somewhere...if I can a reliable source between the Philadelphia to Harrisburg, PA area.

Also, if any can suggest any good techs between the Phila and Harrisburg area for amplifier rebuilds (Adcom GFA-555 II models) I would also appreciate getting a name and address.

Thanks guys...appreciate your help!
Please explain what is wrong with the sound so we can advise. No highs? Loud scratchy noise? No bass? Just not to your liking or terribly distorted?
Did you sell the Kappa 8's yet...? I mean, why pull your hair out trying to get the 9s to sound good in your room if you like the Kappa 8s better?
If they are the 9.1 series 2, I have heard that they draw some serious low ohm loads. If your amp cannnot handle the draw that could add some strain on the system. There are a couple of Infinity Classics groups that have some good information available & some knowledgeable folks.
Here is one link;
The one above is in German, but there is a english forum as well.
The other site is on Yahoo in their forums group.
Good luck, John
Call Bill at Millersound just outside of Philly (215-412-7700). He is THE MAN when it comes to Infinity speakers.
He will make yours sound better than the original.
Tell him Vinh Vu sent you.
Good luck.
I always liked the 8's better. Friend of mine bought the 9's after hearing my 8's and gave up on them because he couldn't find an amp to drive them that he could afford or liked. Yours might be broken. They might make good organ donors for the 8's.

I never got around to doing the surgery on the xovers. There is an RS1b active xover listed now that might help tame the 9's one ohm impedance dip. Paradigm X-30's could work too. Ask an expert. All I know is that the top of the line Infinity/Genesis are active biamped.
Surprised the 8's sound that good with adcoms in the first place.. so obviously you found a rare match that works that smoothly with adcom amps and I would leave it that way.. however you will probably need far better amps for the 9's unless there is just something wrong with them. If keeping the 9's I would look at selling the adcom gear and getting a vintage or newer Mcintosh amp, should be no problems then.
The Kappa 8's sound great no matter what amp I use. The Kappa 9's sound a little muffled and offer no imaging, presence or clarity. I first heard the 9's driven by Adcom equipment in 1987 and that is what sold me on the combination, plus the overall economics. I do understand you get what you pay for as well!

I will contact Bill @ Millersound and drop them off if needed. I assume, until I speak with Bill that he has amps that will drive the 9's even for testing purposes.
If it is an amp issue, that is an easy fix. If it's a speaker issue, I can't offer them for sale in this state and I won't part them out. I maybe stuborn, but it's my nature to find out and know what the problem is good or bad.

In the mean time, I will check the other sites some of you mentioned and see if there's any feed back or experience with the combination of Adcom and Infinity, or more particulars about driving the 9's. Really appreciate everyones help and will keep ya posted.
OK...I got this stright from Bills mouth at Miller Sound!

FIRST...Bill wanted to thank all his friends at Audiogon, for their support and recognition, especially Vinh Vu.

SECOND...Bill said the Adcom GFA-565 was more than sufficient to drive the Kappa 9's...provided they is ample line current and the ability to maintain that current.

THIRD...Bill said the Kappa 8's general much superior speakers than the 9's, without all the fuss!

FOURTH...I should send Bill a digital photo of the woofers. If the foam was replaced and the proper foam was not used, that would considerably inhibit the performance of the 2 - 12" woofers in each cabinet.

FIFTH...Hold some wire leads to the binding posts, + to + and - to -, and lightly contact the + after the - is secure. The 2 woofers should move in the same direction at the same time. If not, they were wired wrong.

SIXTH...absolutely, unequivically, the woofers should be balanced!!! Due to the very narrow profile of the cabinet and it's unforgiving design, if the woofers are not balanced, the before and after sound will be noticeably different. The woofers should take a week or two after receiving to balance.

Looks like I have my homework to do now. Really appreciate everyones thoughts and comments and will post again as things develope!
The Kappa 8's are very good, but they are not in the same league with the Kappa contest. The Kappa 8's are much easier to drive. The bass, highs, midrange and dynamics of the Kappa 9 completely overwhelm the Kappa 8 if the rest of your system is up to it.

To get the best out of the Kappa 9's, you need to biamp them and have amps that are stable down to one ohm. I currently own the the Kappas 7,8 and 9, the Infinity Rennaisance 90 and the Infinity IRS Betas. I own four sets of of the Kappa 9 and will never sell them.

If you don't feed them lots of kickass power, they simply won't respond. Either something was already wrong with the speakers when you bought them or your amp doesn't have the testicular fortitude to get the job done.

I've biamped the Kappa 9 with two pair of Carver Silver 9t monoblocs (900 wpc @ 4 ohms) and they sounded great. I used a pair of Sunfire Signature amps (1200 wpc @4 ohms) to biamp them and they sounded great....and I've used two pair of Pass Labs X-600 monoblocs to power them and they sounded excellent. I used Audio Research LS-10, Reference 1, Ref 2 mk2 and Reference 3 preamps in front of them and the Kappa 9's sang like beautifully.

There is nothing wrong with the Kappa 9

Below are some links to Audiogon testimonials about how good the Kappa 9 sound to very satisfied owners. need a big room for Kappa 9. For small to medium rooms they are overkill.

Mitch4t is correct, I had a set of Kappa 8's and then 9's years ago. I ran the 8's with Bryston 3b's bi-amped and the sounded great. Then I upgraded to the Kappa 9's with thies amp's and the speakers did not preform at all, they sounded withheld and a harsh top end. I did not know what was wrong with them, I heard and read that they need lots of power so I bought a pair of Bryston 4bST's and the speakers came to life, I had a large living room at the time so I also had to play with the positioning as well. they where definitely a superior speaker over the Kappa 8's. Then I bought a pair of Infinity Reference RS1b's and found out the same way that I had to upgrade the power again.
Before I sold my Kappa 9's I tried my Conrad Johnson Preimer 5's(200/ch-85lbs each)mono block tube amp's on the top end and my Perreaux 5150b (500/ch@8ohms-1000@4ohms-140lbs) on the bottom end, their was a big difference again in the sound from the Bryston 4bST's. The bass was aw-some out of them, the mid was smooth and the top was clear and sweet. So of course i demoed the 9's with the big amps to sell them.

I have found with these big infinity speakers, that you have to have a big rooms, position them away from the corners and form the back walls. You have to spend money on high power big current amp's, other wise you will not get the benefit's out of them.

Good luck and have fun with them,
If the crossover netwok is in great condition you should notice that arnie designs all loudspeaker with tube eletronics. Most customers were satisfied when they used a tube amp
Hi All,

so so I have fallen almost all the way down the Infinity Kappa rabbit hole...  I am now the proud owner of Infinity Kappa 7's, 8's and 9's.  I started at 7, jumped to 9 and have kinda landed on 8.  7's do a bit better imaging as they are more simple 3-way, 8's are pretty close on the imaging but feel more effortless, airy, inviting. The Kappa 9's suck!  Honest.  I am using a Carver Sunfire Signature which I believe is 625watts x 2 into 8ohms and should be more than enough but I've also have used in bi-amp configuration a Behringer Europower Ep4000 which I believe is 2000watts x 2 into 2ohms (class H) and a Crown XLS1500 (class D) 775watts x 2 into 2ohms. Using this in a bi-amp configuration I can almost get the 9's to sound reasonable, but not good.  In general the 9's are all midrange (polydome mostly) and nothing else? Can anyone tell me what the steps are for troubleshooting the 9's?

The previous owner had the polydomes recovered with that silly transparent silicone material and I have since dropped in the 4ohm Western Speaker replacements and have swapped in some of my Millersound polydomes. Both of which are way better than the silicone Polydomes. The previous owner also refoamed the woofers himself.

So why am I getting no bass and all midrange? Am I correct that I am using enough amp to drive these?

...I just don't understand why the 9's sound so much worse than the 8's and 7's. Any help would be greatly appreciated.


Usually the issue folks have with the bass on the Kappa 9s is the the woofers are wired wrong. The should be wired in series. The positive wire will go to the + terminal of the first woofer then a short wire will go to the - terminal of the first woofer and then to the + terminal of the second and of course the negative wire will go to the - of the second woofer.
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I own A set of Kappa 9 and when I rotate them into my main system ( powered by 2 Krell Fpb400cx) the bass slam is incredible 
I know another issue some have had is no polyfill inside the cabinet. It makes quite a difference.
dstechlabs on the Bay has new and improved crossovers for the Kappa 6, 7, 8 and 9. Prices range from $345, 395, 445 and 495 - with free shipping within the lower 48! These address and remedy the below-2 ohms impedance of the stock x-overs. Overall improvement in sound quality and a more amplifier- friendly load for the amplifier! If I owned any of the Kappa's I would buy a pair of these x-overs!
Personally, I wouldn't recommend the DS Tech Labs crossovers.  They totally disregard the original designs, with their crossovers.  In the case of the 9's, they turn a 5-way system into a 3-way.  The Semits and Emits are combined together, and the Polydome and Polygraph domes are combined together as well, with their boards.  You might as well buy Kappa 6's or 7's, and not waste your money.

Also, I wonder if the OP ever resolved his Kappa 9 issues?  Did Bill LeGall help out?  It sounded like the woofers might have been miswired too.  Out of phase?
Mr. Legall and his organization appear to no longer want to speak with me (via email) since I alerted them they sent back polydomes with a crack in one of the mount plates. 


I will open up the 9’s at some point to check the wiring on the 9’s. Something is wrong. A Carver Signature Sunfire at 635watts should push them but doesn’t. The 9’s are too big for my room as well 12x17.

For now I am enjoying my 8’s and a Crown XLS1500 amp...amazing an amp I picked up for $75 generally sounds better than Adcom 555ii and the Carver. More three dimensional...Carvers highs were more pleasant, Adcom mid bass was tighter.

Added a second Crown amp today...each speaker is now getting 1500watts (4ohms) of Class D power.  Three-dimensionality increased, bass presence increased, a bit
more ‘relaxed’ sounding in the middle.

Still think there is something wrong with my room as I have trouble resolving male voices and snares sometimes... Mid cohesion seems to be a problem.  Any ideas anyone?

Going to try the bridged Crowns on just the highs, engaging their high-pass filters and throw my Behringer EP4000 on the lows. Should really help the mid and high resolution. 
 Infinity Kappa 9's sound terrible...HELP

These could need a very good amp that can deliver gobs of current, if we could see what the -phase angle graph looks like.

As they look to be an evil load to an amp at 35hz and again at 7hkz already, this is just the impedance plot of them, with a -phase angle plot as well combined they could look even worse.

Cheers George