amplifiers for Kappa 9's

The impedance of those speakers gets very low which would probably be a problem with most tube amps. I know a Parasound HCA 3500 will drive those too but many amps won't due to the very low impedance. Do a search here and you'll find more info.

I was checking out the crossovers in these speakers a couple of weeks ago at a friend's home. WOW these things have a lot of real estate inside of them! Just from the looks you need a mammoth amplifier to get the best out of them. I bet a Carver ZR1600 would spank them like a red headed step child.:-)

Good luck with finding a tube amplifier for those monsters!

Those speakers would suck a Carver Pro ZR1600 dry. You need BIG power with those if you really want to raise the roof and keep things relatively clean. Sean
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Hey Sean how about two Carvers run as monolocks? You think it would suck them dry? I have no doubt they need some serious current. With all those parts, it's a wonder any signal ever makes it to the drivers.:-)

Or how about a Carver ZRx3200 1600 wpc into 2 ohms. Or two ZRx3200 monoblocked with 3200 wpc into 4 ohms! This model may do the trick.LOL

Unless you get an amp that can provide massive amperage, you will fry your Kappas. The best seem to be old Aragons, I think the 4004 or was it the 8008BB, my memory fails....they were designed by Krell. They continue doubling down to less than 1 ohm...very few amps can do this.

I am a little apprehensive of the Parasound 3500...some owners reported problems with humming transformers.

No digital amp, especially those with questionable power supplies will ever, NEVER, drive these beasts. It was commented to me by Rick Schutz from EVS, that digital amps have terrible power supply sections, they are overrated in the specs.

Go with the heaviest hitting SS, preferably Class A or similar that is heavy, especially to power the bottom.

The top, I would also recommend decent power.

Finally, make sure you can committ to spend some money in dedicated powerlines for the amps to run the Kappas. The harshness that you hear has a lot to do with current starved amps.

There are some mods you can do on those Amp Killers, cabling seem to be common to be exchanged and some people also talk about better stands than those pathetic slabs of MDF or something.

Decent, massive power and enough current is the key.

BTW, I have a pair of parked Kappa 9s that have been in my mother's garage for the past 16 years...mint, boxed sets.

The Kappas are amazing for what they do, and something similar to them today would go for $$$$$ more. Once you get them set up properly, very few speakers out there can do what they can. The last batch of speakers designed by Nuddel? who went on to found Genesis...see what the Genesis cost, ouch.

There's an Agon member here running two Sunfire Signature's for his Kappa 9's. At the low impedances that these speakers present, he has 1200+ wpc for the top end and 1200+ wpc for the bottom end. These ratings are based on a 4 ohm load. If you wanted to consider this speaker closer to a 2 ohm load, which may be somewhat conservative over much of the range of operation as it drops to below 1 ohm i think, he's got 2400+ wpc for the top end and 2400+ wpc for the bottom end per channel. This is without bridging, so damping factor is not compromised.

Having said that, i don't think that two ZR1600's could do the job here. The limited testing that i've seen on these amps wasn't very favourable. Most all of this can be found in the archives though as this speaker is notoriously hard to drive, hence the subject coming up a couple of times before. Sean
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Here is the impedance curve for the Kappa 9's.

http://f4.grp.yahoofs.com/v1/wLtQQtJS003JLQWVCsufEZM95gi5uACVW5ItP_G1a7hnt5eNa9-cVaCZNzyLVt_QjjNhT1i1M2Bt-JMajpCYlvqVDszIGdxD/Infinity%209%20Kappa%20Impedance%20Curve.jpg

Bemopti123
Are you sure about Digital amplifiers not ever never being able to drive such a load? Those are pretty strong words my friend. I know some of you fellas are from that old school.I seriously doubt an amplifier like the Carver ZRx3200 would have a problem driving these speakers. I've come to realize Paul you really dislike Carver products.
Even though these amplifiers aren't under Bob Carver's name, you seem to associate the two. Carver pro is a different company. I would love to see your face with this amplifier hooked up to those speakers. I guarantee you would have to eat those words! These amplifiers do use toroidal transformers if you didn't already know. Here we go again with the generalizations.

I'm so glad you mentioned Ric Shultz. I contacted him sometime back about his Beta amplifier which uses ICE power modules. Guess what power supplies it uses.. switching power supplies! Here's a qoute from his website.

Dual mono (each amplifier module has its own separate power supply). These modules use switching power supplies. Some people feel that switching supplies (like Peter at Acoustic Reality who uses linear supplies with his modded Ice Power modules) are less good than linear supplies.....then there are those who feel switching supplies have advantages over linear supplies.....My take is that whatever type of supply you use, it must be tweaked or you have no idea of what it is capable of. The stock Ice Power module sounds....well....lets say zippy and two dimensional.....after our tweaks and mods the module is perfoming better than the Ice Power modules that we were using that use linear supplies....these tweaks were to the power supply and other things. What matters in the end is how something sounds....this is what you guys will determine.

Either you or him isn't telling the truth. Which one is it?
Quoting from the great Homer Simpson..DALT! LOL

John Curl measured a Carver Pro ZR1600 and it was so distorted at 180 wpc @ 8 ohms, that he was afraid to push it any harder than that. Much of the distortion that he was seeing was high frequency artifacts from the very poorly designed power supply, but none the less, the amp wasn't performing up to rated spec. Since most amps produce measurably more distortion as impedance is reduced, trying to run such an amp with a very demanding low impedance speaker would only aggravate the problem.

From what i know, this amp was given to him by Brian Cheney of VMPS to test. Brian had verified that the amp was working and sounding "quite good" when Curl received it. As such, one can only speculate that this wasn't a defective model or anything like that.

Supposedly, "Carver Pro" ( who is reallythe car stereo company known as "Phoenix Gold" ) have made some design revisions to these amps based on "audiophile feedback". Given that i've never seen any follow-up on the amps after that point, i don't know if they will actually meet and possibly exceed spec or if they are still in the same boat. As such, buying another model that is rated for more power from Carver Pro may get you more power, it may not actually get you the amount that they are rated to produce with a reasonable amount of distortion. This is strictly conjecture on my part though, as i've stated that i've not seen any further follow-ups on this brand. Sean
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Sean with all do respect. That would be the same if I drove a Ford over to Chevrolet for inspection. And ask them to give me an honest assesment on it.LOL

Seriously though..I've seen this beat to death about the distortion ratings. One guy claims distortion from the tripaths chips at 50 khz and 70 khz. Who the hell listens to anything at that frequency ? :-)

Some of the same proponents against switching power supplies and digital amplifiers go to live concerts where these are the only amplifiers used. Then they come home and brag about how good things sounded.

I never see anyone downing David Bernings amplifiers. Some of the same audiophools that generalize about switching power supplies. Can't wait to drop $4500 on this tube amplifier that uses basically a switching power supply.
Go figure! I've come to the conclusion ..listening is the only way to know. The measurments have their place but it's not with this type of technology IMHO. Maybe someone needs to come up with a different type of measurements for this technology. You seem like a good candidate Sean.Your super technically inclined. How about it ? Let me not leave Eldartford out, you guys should team up. :-)

I challenged statements made in a Berning based thread where both David Berning and one of his cohorts responded. After a series of exchanges that built upon the foundations of where we were all coming from, i asked further questions / made further statements pertaining to the Berning amps and how they would interact with various loudspeaker loads. For some reason, those questions went unanswered even though the other parties continued to post in that thread. Somehow, the points that they couldn't refute or explain were conveniently overlooked.

As to bringing a Ford to a Chevy dealership, etc... Curl has designed gear for dozens upon dozens of manufacturers. Believe me, from his point of view, a design or circuitry that is new to him is a chance to learn about something that he may not be familiar with. Nothing more, nothing less.

As to high frequency artifacts not affecting what we hear, this isn't completely true. High frequency response above the audible band can directly alter in-band response in the ways of transient response, phase shifts, various types of distortion, etc... This is why i've said that spec's ARE important, but you have to look at ALL the spec's and be able to interpret them effectively. Looking at a few individual spec's here and there can be phenomenally misleading, good or bad. Sean
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Kjak67,

Sean was referring to me running Kappa 9's wirh a pair of Sunfire Signature amps in a vertical biamp setup. I also ran them with 4 Carver Silver 9t monoblocks. As far as I'm concerned, biamping them is the only way to go to get the most mileage out of those boys if you don't have a lot of money to spend on amps. The Sunfire Signature stereo amps can be had here on Agon for $1500 to $1800. The Carver Silver 9t monoblocks can be had for $1200 to $1500 per pair.

One pair of Carver monoblocks or one Sunfire Signature stereo amp will drive the Kappa 9's satisfactorally, however, biamp them and it's a different world.

The Sunfire amps were better all around from top to bottom, the bass was very good with the Sunfire amps, but could not duplicate the bass slam of the Carver monoblocks.

Whe I was running my Kappa 9's, I lived in a loft that was 22 x 70 ft with 20 ft ceilings. The Kappa 9's using the 4 Carver monoblocks or the two Sunfire amps filled the room with music to the brim with lots of headroom to spare.

I own two pair of Kappa 9's. I have lent one pair to a friend and the other pair is in storage. Hopefully, one day I'll own a room big enough again to let them stretch out and do their thing again with some serious high end amplification. My current room is 17 x 20 feet with 9 ft ceilings....the Kappa 9's were just too physically dominant in my current room and my wife wouldn't have it......so I am now biamping a pair of Infinity Rennaisance 90's with a pair of Sunfire Signature amps and life is good.

good luck in your quest

Gmood, I do not dispute your info on the Carvers, but then, why isn't there a Kappa 9 owner out there that is driving these ampeaters with the latest holy grail in audio amplification? I trust that these owners have been experimenting with older SS behemots as most Kappa 9 owners will try. I personally do not believe that I would ever try to let them run fullrange with an amp like the Carver Pro.

One word on caution: play with underbuilt amplifiers and the Kappa 9 and you are risking massive failure of either the amp or the Kappas, I would not risk the Kappas with inadequate amplification.

Remember another word: dedicated power supplies!

The last time I remember running the Kappas, it really juiced up the electricity of my outlets....could even see the lights pulsating with the volume going up and down.

hehehehe.

Kjak67, I just went through the same thing that you are now going thru. Seems like all the same posters are still here. AS a ownwer of a set of Kappa 9s I can say that Bemopti 123 knows what he is talking about. The Aragon 8008 or palladium amps are a good way to go for sure. There are no speakers out there that these Aragons will not drive (END OF CONVERSATION) I'm not saying that the Carver amps will not do the job I'm just saying you need to look no further then the Aragons that are availible right here on the "gon" for 3K a pair brand new. I would like to try Mitch4ts idea of Bi-amping these speakers but right now I don't have enough A.C. power in my room for addtional amps. This summer I will be remodeling my house and I will pull more circuits and give it a try.