amplifiers for Kappa 9's

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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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

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

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. :-)