Recommendations for power Infinity Kappa 9's pease

[jtiesel]

I own a pair of Infinity Kappa 9's that I am trying to find power for.
Owners Manual Specs:
Nominal Impedance: 4 to 6 ohm (recommends amps that can go lower)
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 specs:
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
These speakers are 5ft tall and require lots of power. In the manual it says that each speaker can be bi-amped and recommends giving the most power to the woofers.

I'm looking for people who have experience powering heavy duty speakers to recommend a budget (I will be shopping ebay, craigslist, and sites like overstock.com) solution for the power needs of these speakers. Any thoughts, experiences, or words of wisdom would be much appreciated
Thanks

[Mr Peabody]

I've seen the 9's bring many a good amp to the tech bench. You need current, those babies drop low in impedance swings. They are cool speakers though if you find the amps to run them. Keep in mind it's not so much the power as the current the amp can produce. Not many mid-fi amps are going to do it, not Carver, NAD, Proton, Sumo, I've seen them all go down.

On the least expensive side you could try Adcom 5500 or 555, nothing less. The biamping may be a good idea. From there if you have the budget look for Krell or Bryston.

You might also try a XPA-2 from www.emotiva.com I don't have personal experience, they look good on paper and priced right. They give a 30 day trial.

As a side note that's the first time I've seen a sensitivity rating that high. I thought the 9's were in the 88dB range as the rest of the line. That seems to be the rating Infinity is showing now. The 12's in the sealed enclosure sure produces some low end. I used to have a pair of 7's.

[Mr Peabody]

I also heard of a guy who had some 8's that he drove with an Integra power amp. Any amp capable of producing enough current will also need plenty of ventilation so you should either have an open shelf or maybe place the amps in the open close to the speaker.

[jtiesel]

Thanks for the quick responses! I have already seen an adcom gfa 5500 for $400 online which is the top of my price range. This is probably a silly question but could someone please explain to me how current is measured? What should I be looking for in an amplifiers specs, or my speakers, that defines the provided/required current? Also I was planning to have a pioneer 40w/channel receiver power the mid-ranges and tweeters of both speakers, then use something like the adcom 5500 to power the woofers, does this sound like an ok setup?

[eisforelectronic]

current is usually expressed as amperage on specs for receivers. Harmon Kardon lists it as a spec. I think I've seen it on some Denon specs as well. Lots of receivers don't list it at all. Rule of thumb is if it's not listed, it's probably not very high.

[Mr Peabody]

The set up you want to use might work temporarily. I suspect the Pioneer will go into protection a lot or die. The 5500 is a good amp I'd probably just run the speakers full range with that until you can afford another amp for the top end. The 5500 will be far superior sound from the Pioneer.

As far as what to look for in "high current" I'd have to do some checking to see what amperage would be considered high but a rule of thumb is look at the power rating into 8 ohn and then into 4 ohm, if the power doubles or close to it into 4 ohms it's probably a high current amp.

If Adcom is your budget run the 5500 until saving up then look for a 5400, 545 or another big boy for the top. The top end will swing low in impedance as well. The 5500 may be all you need but if you biamp I suspect it will help the amps and may sound better. As stated earlier keep the Pioneer for another job biamping with that would really not be good.

[jtiesel]

There is an adcom 555II selling for 350$ in my area. Would that be able to run either the low or high pass or possibly both?

[blackraven]

Current is measured in amps and you may see it listed in peak amps. 30 or more would be considered high with 30 being on the low end. Generally, 45-60 peak amps is high.

Here's a used Van Alstine Omega III 200wpc power amp with a warranty for $595. It should drive anything you throw at it. Give Frank Van Alstine a call and discuss your concerns. He always answers the phone.

http://avahifi.com/index.php?option=com_content&view=article&id=125&Itemid=176&74a0ad6b5f7a1df0ef4ab98b8fffbb41=550cd645ec1be1c77 9cff8d9418108dc

[Mr Peabody]

The 555 and 5500 are both 200x2, the 555 is an older model. Both are good amps. If you could buy both it would be the best but I believe either could probably run the 9's in full range.

[efertheredfish]

Hello

it seems to be pretty amusing what was recommended above. There is one thing you can be sure. After having the crossover repaired to met its orginial specs and woofers refoamed you should consider that your louspeaker is like new, so I would enourage you to use newer eletronics, becouse they surpass the preformance with the loudspeaker.

If you want to drive the whole loudspeaker with one amplifier I would recommend you the Modwright KWA 150 power amplifier. It sounds better than the Pass amp and even more natural in the mids and highs.

If you want to biamply I would certainly encourage you to use a vaccum tube amplifier for thr midrange and tweeter. I have tried the Balanced Audio Technology BAT 150 VK Se and it sounded beyond my dreams.

For the preamp I'm thinking about an Asthetix Calypso or a Modwright SWL 9.0Se.

This amps aren't cheap, but the Kappa 9's are close to the Genesis 3 in preformance and they sound excellent with that amps. It is often said that the Polydome produces harshness or shrillness, but once you hear them with newer eletronics or tubes in the mids and highs it sounds almost totally different. (airy and spaceous)

Hope that helps.
Stefan

[efertheredfish]

The Emotiva 2 doesn't have the power to drive the Kappa 9's , but I was very impressed with the XPA-1 on the 9's.:hand:

[bfalls]

The Emotiva 2 doesn't have the power to drive the Kappa 9's , but I was very impressed with the XPA-1 on the 9's.:hand:

Wow! It must be quite the load. The XPA-2 is capable of 300w/ch, has a 1.2KVA transformer and additional 450,000uf secondary capacitance. The Kappa's spec say the load is 4-6 ohms. The output must be at some incredible phase angles.

I have the XPA-5 (200w/ch 8ohms) driving my Legacy Focus mains. They have three 12" woofers, 2 7" mids and two tweeters with only 94db efficiency instead of the Kappa's 102db. It has no problem driving the Focus. I've had them bi-amped before which helps with adjustments, but I didn't really notice a difference in power.

[Mr Peabody]

Glad we could amuse you Stefan, if you took in the entire thread you should have noticed the OP has a limited budget, so BAT is as out of range as the Krell or Bryston I mentioned in an earlier post. The Adcom and Emo are capable of producing decent amounts of current, may not be optimum but far better than a receiver. As I mentioned I personally haven't had hands on the XPA-2 but on paper and with the number of output devices it looks like it shouldn't do so bad at driving the 9's.

IMO if some one found the Poly Dome harsh there must have been a problem. I always found them to be very smooth. They were made by Vifa.

Bfalls, the 9's may be rated at 4 to 6 ohms but the impedance isn't stable and can dip dangerously low for all but quality amps capable of high current.

[bfalls]

[QUOTE=
Bfalls, the 9's may be rated at 4 to 6 ohms but the impedance isn't stable and can dip dangerously low for all but quality amps capable of high current.[/QUOTE]

I understand that completely, that's why I mentioned phase angle as well as impedance. I know it's not all about impedance. I've been reading speaker reviews for over 40yrs. Having an electronics degree I understand all the speaker graphs.

Still I believe the XPA-2 could handle the current requirements of the Kappa 9s. At least as well as the Adcoms.

[Mr Peabody]

The XPA-2 should actually be some better than the Adcom on paper. Now that I have more experience with higher end gear it would be fun to go back and hear the 9's again to see how they do.

[Feanor]

There is an adcom 555II selling for 350$ in my area. Would that be able to run either the low or high pass or possibly both?
I have owned the 555II. It's a fine, slightly dark sounding amp and capable of driving 2 Ohms. It would do the job quite well, and is a bargain at $350.

[efertheredfish]

@ Mr.Peabody.

Ok the cheapest working soloution is in my opinion a Parasound HCA2200 (500$) for the woofers. For the midrange and tweeter you can use a Sonic Frontiers Power 2 (1200$).
Then you need a gain controller to adjust the attenuation of the low frequency and high frequency ampliifers. ( FIRST WATT BUFFER B2 300$ if you email Nelson Pass)
As a preamp you can use a Prima Luna tube for 300$.

With the HCA220 you can drive the whole speaker too.

You do not need to buy all at once, but I would recommend this combination as a lower priced one. It doesn't make sense to buy a cheap Adcom that can't really drive those speakers and as I have talked with Arnie he still would recommend a tube amp for the midrange and tweeter becouse its sounds simply excellent on the Kappa 9's.

I hope this helps.

[efertheredfish]

If you do not have the budget at all start with the HCA2200 and drive the whole speaker with that power amp.
Any other amp inclduing the Adcoms and the Aragon's are unstable and cannot drive that speaker in extended mode. The HCA2200 works very well even at high volume levels.

Cheers
Stefan

[efertheredfish]

http://cgi.ebay.com/Parasound-HCA-2200-200-watt-ch-67-pound-amp-/170627057602?pt=LH_DefaultDomain_0&hash=item27ba2a47c2

Grab this one as long as you can!

[Mr Peabody]

If the 2200 is a Halo it may have a chance, if not, it's destine for the service bench.

[blackraven]

Have you guys looked at the date of the initial post?

[Mr Peabody]

Yeah, but I think I was involved back there some place.

[efertheredfish]

If the 2200 is a Halo it may have a chance, if not, it's destine for the service bench.

You have very nice humor my friend. The Adom and Aragon switch off prettily fast. The HCA2200 can drive the Kappa 9's quite well even at very high volume levels. The circuits are built for deliver the current that the Kappa's need hence it is a ultra high current design.
Even at the phase angels of minus 30 degrees the Kappa produces on that load cause the clipping lights to blink. It is usually very funny to watch, but the best thing of all the amplifier stays always on even under those conditions.
Test protocols have shown that the amp works pretty stable under these conditions if you do not pull the knob as far as it will go. :D

Cheers
Stefan

[Raj J]

Good day mate! welcome to the world of "difficult driving" Infinity dinasours...

No pun intended! but I've had many wonderful experiences driving classic speakers, especially Infinities! I used to own a pair of Renaissance 90's (the last true Inifinity classic made by Arnie Nudel); similar specs but sensitivity was far less somewhere around 89dB... nonetheless, as many of us have mentioned you will need a lot of high current and power to match it if you want the best out of your Kappa 9's!

I was using massive Manley 350 watt monoblocks (all tube design) and the preamp at the time was a conrad johnson PFR. Before the Manleys I tried numerous solid state power amps that never really did it for me, here are my ratings.
1. Adcom - crap!
2. Parasound - ok, no musicality at all, just noise...
3. Threshold - absolutely useless
4. Forte - another useless piece of capacitors & transformers...
5. tried out some older Haflers, & Sumo amps - ran out of steam within 30 mins, so did Carver, absolutely no go with any of these cheap amps.
6. Phase Linear - another load of bollocks, shut down after about two hours, cannot remember exactly when, but didn't turn on after that!
7. Accuphase - crap
8. NAD - forget it!
9. Audio Lab x 4 monoblocks - absolute nonsense!
10. B&W 600 watt monoblocks - drove ok, but didn't have the guts for bass, did not shut down held together quite well - yea it better specially at 600w/ch!
11. Carver Lightstar by carver research - drove quite fine, not so musical though.
12. Sunfire - held together quite well, overall balanced sound compared to the above.

All of the above were rated at around 250w to 300w/ch or more, however none of them gave me that musicality factor I was looking for. I went up a few notches, and tried some real quality amps from a few good friends who leant them for trials:
1. conrad johnson MF2300 - excellent! plenty of drive and very musical.
2. Krell KST - very good drive for just 100 watts, plenty of power in reserve, solid imaging.
3. Krell KSA 200 - very similar to the KST with double output and plenty of drive! well capable of driving the inifinities to true potential.
4. Bryston - older version of a 4B SST, capable of delivering somewhere close to 500w at 4ohm loads; excellent power amps to drive difficult loads.
5. Pass Labs older Aleph series, was outstanding! - probably the best overall sound, but the most expensive compared similar to an older Mark Levinson 450 watter that I tried out for a very short while since the owner didn't want to leave his amp over night, can't blame him; another beautiful amp indeed!

Out of all the above solid states, the Krell, Bryston, and Pass Labs amps were the best match! Then I tried some tube high-powered amps, and my golly! now this is what I call music & sound stage with a SLAM! Eventually I bought the Manley monoblocks 350 reference series, and they drove the Ren 90's to their true potential, absolutely no strain whatsoever effortless live scale of music. preamp and CD player were all conrad johnson design, did have a sonic frontiers SFL-1 for a very short while.

I understand that you have a limited budget, didn't we all ...
I must say this though; you have bought a speaker that needs good power to drive, matched with good stable output. The basic mistake you've done is bought the speakers first and now you don't have anything to drive them properly. Biggest mistake so many make! You must always plan to buy your amps first, then match your speakers around this. This way you will not fall short on power, and whatever speaker you upgrade to you will always have ample power to drive them...

You may have the best speaker in the world, but they are only as good as the amps driving them!
The infinity Kappa series are NOT mickey mouse speakers, they are true infinity classics, and require quality gear to get the best out of them. each time I have auditioned a Kappa series speaker they were all driven with some serious Krell gear or Bryston amps on solid state, and massive tube amps from Audio research, Manley, VTL or McIntosh.

Now that you've bought these, you will have to start from scratch; there is absolutely nothing out there of solid state for "cheap prices" that's going to do justice to your Kappa 9's. if there is any amp as I have listed above that is a real bargain in the high-end brands, carefully check it out make sure there is nothing wrong with it, or it has had a major repair...

If I were you, I would invest in a good 100 watt tube power amp to begin with, capable of driving the Kappa 9's within reasonable levels. some where around $1000 to $1500 should get you a good tube amp between 100w to 150w/ch that can easily drive the kappas. after you have saved enough, I would then upgrade to either a higher output tube amp somewhere around 300 to 450w/ch and you will be amazed at what the kappa's can really do! At the moment you don't have any idea, hence the reason I said you've bought these speakers without considering some serious amplification...

If you do eventually want to go solid state, I would save enough for either Krell, Pass Labs, Mark Levinson or Bryston on a more affordable scale.
All the other makes as mentioned in my previous list, will probably drive the Kappa's to some degree, but will never make your Kappa's sound like a "real Kappa!"
Ask Arnie, and he will tell you directly what he has created; the Kappa series can deliver a true live performance if partnered with the right equipment, and it is a beast to drive - period!

If you are on tight budget, I would plan the following:
(tube power)
(1) 100 to 150 watt tube amp to begin with, for a good second hand value with matching preamp.
(2) upgrading to 200 to 250w in step two with better preamp in the long run and your Kappas will sing!
(3) eventually getting the big monoblocks to drive your kappas, 300 to 400w and you will be performing with the band on the stage itself!

Solid state power:
(1) get hold of either Bryston, Krell, MacIntosh, or Conrad Johnson will easily match well, special bargains may be out there with a good preamp.
(2) aim to upgrade to around 400w plus on solid state gear and you will begin to notice what the Kappa's are about.

Once you've reached this level, you'd probably think there is nothing better..., until you've tried some high-powered tube amps!
All the best and let us know how it goes...
Cheers, Raj J

[efertheredfish]

Good day mate! welcome to the world of "difficult driving" Infinity dinasours...

No pun intended! but I've had many wonderful experiences driving classic speakers, especially Infinities! I used to own a pair of Renaissance 90's (the last true Inifinity classic made by Arnie Nudel); similar specs but sensitivity was far less somewhere around 89dB... nonetheless, as many of us have mentioned you will need a lot of high current and power to match it if you want the best out of your Kappa 9's!

I was using massive Manley 350 watt monoblocks (all tube design) and the preamp at the time was a conrad johnson PFR. Before the Manleys I tried numerous solid state power amps that never really did it for me, here are my ratings.
1. Adcom - crap!
2. Parasound - ok, no musicality at all, just noise...
3. Threshold - absolutely useless
4. Forte - another useless piece of capacitors & transformers...
5. tried out some older Haflers, & Sumo amps - ran out of steam within 30 mins, so did Carver, absolutely no go with any of these cheap amps.
6. Phase Linear - another load of bollocks, shut down after about two hours, cannot remember exactly when, but didn't turn on after that!
7. Accuphase - crap
8. NAD - forget it!
9. Audio Lab x 4 monoblocks - absolute nonsense!
10. B&W 600 watt monoblocks - drove ok, but didn't have the guts for bass, did not shut down held together quite well - yea it better specially at 600w/ch!
11. Carver Lightstar by carver research - drove quite fine, not so musical though.
12. Sunfire - held together quite well, overall balanced sound compared to the above.

All of the above were rated at around 250w to 300w/ch or more, however none of them gave me that musicality factor I was looking for. I went up a few notches, and tried some real quality amps from a few good friends who leant them for trials:
1. conrad johnson MF2300 - excellent! plenty of drive and very musical.
2. Krell KST - very good drive for just 100 watts, plenty of power in reserve, solid imaging.
3. Krell KSA 200 - very similar to the KST with double output and plenty of drive! well capable of driving the inifinities to true potential.
4. Bryston - older version of a 4B SST, capable of delivering somewhere close to 500w at 4ohm loads; excellent power amps to drive difficult loads.
5. Pass Labs older Aleph series, was outstanding! - probably the best overall sound, but the most expensive compared similar to an older Mark Levinson 450 watter that I tried out for a very short while since the owner didn't want to leave his amp over night, can't blame him; another beautiful amp indeed!

Out of all the above solid states, the Krell, Bryston, and Pass Labs amps were the best match! Then I tried some tube high-powered amps, and my golly! now this is what I call music & sound stage with a SLAM! Eventually I bought the Manley monoblocks 350 reference series, and they drove the Ren 90's to their true potential, absolutely no strain whatsoever effortless live scale of music. preamp and CD player were all conrad johnson design, did have a sonic frontiers SFL-1 for a very short while.

I understand that you have a limited budget, didn't we all ...
I must say this though; you have bought a speaker that needs good power to drive, matched with good stable output. The basic mistake you've done is bought the speakers first and now you don't have anything to drive them properly. Biggest mistake so many make! You must always plan to buy your amps first, then match your speakers around this. This way you will not fall short on power, and whatever speaker you upgrade to you will always have ample power to drive them...

You may have the best speaker in the world, but they are only as good as the amps driving them!
The infinity Kappa series are NOT mickey mouse speakers, they are true infinity classics, and require quality gear to get the best out of them. each time I have auditioned a Kappa series speaker they were all driven with some serious Krell gear or Bryston amps on solid state, and massive tube amps from Audio research, Manley, VTL or McIntosh.

Now that you've bought these, you will have to start from scratch; there is absolutely nothing out there of solid state for "cheap prices" that's going to do justice to your Kappa 9's. if there is any amp as I have listed above that is a real bargain in the high-end brands, carefully check it out make sure there is nothing wrong with it, or it has had a major repair...

If I were you, I would invest in a good 100 watt tube power amp to begin with, capable of driving the Kappa 9's within reasonable levels. some where around $1000 to $1500 should get you a good tube amp between 100w to 150w/ch that can easily drive the kappas. after you have saved enough, I would then upgrade to either a higher output tube amp somewhere around 300 to 450w/ch and you will be amazed at what the kappa's can really do! At the moment you don't have any idea, hence the reason I said you've bought these speakers without considering some serious amplification...

If you do eventually want to go solid state, I would save enough for either Krell, Pass Labs, Mark Levinson or Bryston on a more affordable scale.
All the other makes as mentioned in my previous list, will probably drive the Kappa's to some degree, but will never make your Kappa's sound like a "real Kappa!"
Ask Arnie, and he will tell you directly what he has created; the Kappa series can deliver a true live performance if partnered with the right equipment, and it is a beast to drive - period!

If you are on tight budget, I would plan the following:
(tube power)
(1) 100 to 150 watt tube amp to begin with, for a good second hand value with matching preamp.
(2) upgrading to 200 to 250w in step two with better preamp in the long run and your Kappas will sing!
(3) eventually getting the big monoblocks to drive your kappas, 300 to 400w and you will be performing with the band on the stage itself!

Solid state power:
(1) get hold of either Bryston, Krell, MacIntosh, or Conrad Johnson will easily match well, special bargains may be out there with a good preamp.
(2) aim to upgrade to around 400w plus on solid state gear and you will begin to notice what the Kappa's are about.

Once you've reached this level, you'd probably think there is nothing better..., until you've tried some high-powered tube amps!
All the best and let us know how it goes...
Cheers, Raj J



Paul and Arnie told me that they don't like and recommend the sound of the Krells for this speaker. They work pretty well for the woofers, but they are at least unmusical for the midrange and tweeter. If you have the budget and want the amp the Kappa 9's have been developed with you might look for an Audio Research M300.

I agree with most of your statements expect one. I do not know why you say the Threshold's are useless. They are still at the forefront amps when you look to match Genesis and Infinitys to the midrange and tweeter panel and they sound pretty similar to my M300's.

Best,
Stefan

[blackraven]

You might want to consider this AVA amp with the double die option rated at 220wpc @ 8 ohms and can drive 1ohm loads.

http://avahifi.com/index.php?option=com_content&view=article&id=166&Itemid=209

or this FET Valve hybrid amp with the triple Die option rated at 280wpc at 8ohms, over 500wpc at 4ohms and can drive 2 ohm loads.

http://avahifi.com/index.php?option=com_content&view=article&id=153&Itemid=209

[efertheredfish]

At 500$ there is no amplifier on the market expect the HCA2200 that can drive such low impedance loads the Kappa 9's will visit.
The guy doesn't want to spend more than 400$, so I think a better suggestion like the HCA2200 in that price range doesn't even exitst.

Its not the most musical amp, but it works....

[Feanor]

At 500$ there is no amplifier on the market expect the HCA2200 that can drive such low impedance loads the Kappa 9's will visit.
The guy doesn't want to spend more than 400$, so I think a better suggestion like the HCA2200 in that price range doesn't even exitst.

Its not the most musical amp, but it works....
Or maybe there is if you're will to consider a pro amp, e.g. this Yamaha P2500S, here (http://www.bhphotovideo.com/c/product/274444-REG/Yamaha_P2500S_P2500S_Two_Channel.html).

http://www.bhphotovideo.com/images/images345x345/274444.jpg

[Raj J]

Hey Stefan,

Funny thing this post was initially done somewhere in Sept 2010... and here we are still giving our expert advice, this guy has probably forgotten us by now!
Driving Kappa's with some mediocre amp, trying to get the best out of it will no doubt result in blown up units or will completely shut down; I truly hope he manages to find someting decent eventually...

Speaking of Krells: they don't really tickle me, they just have enough muscle to drive about anything, other than that the musicality factor is missing a great deal!
With regards to solid state I prefer Mark Levinson or Pass Labs, or Bryston on a more affordable level that can also drive about anything out there. However, I personally don't like solid state sound!
To me Threshold is really not up to the mark when compared to any of the other top brands I just mentioned, even MacIntosh or McCormack sounds far better to my tastes. I also happened to listen to a pair of massive 800watt Threshold monoblocks driving a pair of huge B&W Matrix 800 (7ft tree trunks!); in terms of power, dynamics, guts, bass to rip your clothes off and of course bring down a few tiles from the roof it was all there. BUT there was absolutely no MUSIC! My 60watt conrad johnson MV60SE with KT120 tubes beats the overall sound by a FAR margin; Tubes rule!

I understand you have the Audio research M300 amps, nice! They are very fine amps, and is a hybrind design of course which I have had the pleasure of listening to driving a glorious pair of Apogee Divas. They were in mint condition, and the sound was very musical indeed. Compared to Threshold, no way not even close! There really is no point trying to compare solid state with tubes...

There are many music lovers, audiophiles, enthusiasts etc who will strongly stand for solid state - so be it! They enjoy there music through transistors and enjoy listening to their favorite tracks via solid state gear, that's great mate!
As for me and the other vast majority of true music lovers, there will always be tubes somewhere in the chain, you cannot deny that! In all of my 25 years & over dealing with 2 channel audio systems in various forms, shapes & sizes - I can still place a little tube amp side by side against a massive solid state monster, and at once notice the natural tones of music through that tube amp regardless of the brand.

I now have the Quad ESL 2905's being driven with a simple pre-power combination from conrad johnson and a vacuum tube CD player; this is musicality at it's finest!

We all sincerely know, and cannot deny it that "under driving" quality speakers will get you no where... That's why I keep telling those enthusiasts to first get your amplifiers; build your system around the amp and not the speaker, unless you have the big bucks!

Trust you are enjoying your music to the max and very satisfied with those lovely M300's!
What speakers and preamp are you using by the way?
Have a good one,
cheers, Raj J

[Mr Peabody]

I understand where you are coming from Raj, but "musicality" is in the ear of the beholder. The thing that Krell does that I have yet to hear tubes match is bone jarring transient response. The sound is also very quick and nimble. Just saying some may feel that type of presentation is more musical.

[efertheredfish]

Hello Raj,


They are good amps for the woofers, but they can't handle the transparency in the midrange and tweeter region.
The Thresholds are almost perfect and becouse the STASIS circuit makes them sound like a tube amp. If you do not want to have retube and it is a perfect match for Infinity hence it makes appear the ribbon to become crystallic clear which on the other hand doesn't work with the Krells.
John Gordon Holdt and Arnie Nudell seleted therefore the Thresholds as an fabolous soloution to the Infinitys if you do not like to have a tube amp. If you use a tube pre your as good as with the M300's. There is not much sound difference in my setup no matter what i use becouse i pair it correctly. ( tube pre)
The STASIS Series were tested on the IRS, Gamma, Beta, RS-1 and they sounded like a dream!
The M300's have many disadvantages they are not working stable at 230V here in Europe and if the tests points aren't set correctly they are a disaster. They are expensive in repair. I retube once a year and the costs aren't cheap. They aren't my favourite stuff. Conrad Johnson is better, but you can also use a tube pre and the Threshold for the Kappa 9's and they sang as good in the lower frequency region even better than the M300's.
Match the components right. Thats the glue.
When Arnie selected Threshold as an option you can't go wrong. You just do not like the sound of this amp, but its pairs nearly perfect!
What you want with Bryston. They are far too low powered for all the Infinitys and noone would recommend them.
The Adcoms cannot drive this speaker. They have a good circuit, but they are not a high current design. My suggestion for 500$ on Craigslist, the HCA2200 works nearly perfect and it was tested during that time with the Kappa 9's. It is not a new amp where nobody knows if it works or not. It does pretty well. It isn't the most musical option, but I understand this guy.
We here have an Inflation about 4%. Its pretty silly to drive to car wash and pay 12$ when you select the cheapest washing programm. SILLY???
The Pass nearly have the same circuit and I agree that they sound well on the Kappas.
Also your infos that a 200 Watt tube amp sounds fine and a higher powered one better.
Man, the output transformer has to be designed with two ohm windings switched with another one parallel or one ohm windings at the output tap to match the low impedance with the Kappa 9's.
There are 50 watt tube amp outside that sound better than your suggestions here in the forum!

We all know there are a lot possibilities, but we should come back to the origin of this post to recommend very low priced affordable electronics to drive the K9's. Anything else is good to hear, but wont help this guy much.

My suggestion is a 300$ tube pre from Prima Luna and the HCA2200 to drive the whole speaker.

That should work and shound quite fine!
Cheers
Stefan

[efertheredfish]

Some other working amps come in my mind, but i do not know how they are dealt in the US.

Nakamichi PA7E
FORTE 1A ( a pair to drive the kappa 9's)
Vincent D150

[Mr Peabody]

I have to disagree, the larger Adcom 5500/555/545/5400 are high current design, that's a fact, whether enough to drive K9's not sure. Interesting you'd put them down since they too are Pass designed. I used the 5400 & 5500 on Dynaudio 4 ohm speakers, which are pretty stable, the amps rocked them without breaking a sweat.

Also, Bryston are rock solid high current amps which are in an entire higher level from Adcom.

[efertheredfish]

I have to disagree, the larger Adcom 5500/555/545/5400 are high current design, that's a fact, whether enough to drive K9's not sure. Interesting you'd put them down since they too are Pass designed. I used the 5400 & 5500 on Dynaudio 4 ohm speakers, which are pretty stable, the amps rocked them without breaking a sweat.

Also, Bryston are rock solid high current amps which are in an entire higher level from Adcom.

Both the Adcom and the Bryston cannot deliver the current Kappa's need. If you drive them in extended mode, it switches off pretty fast. The Parasound and Vincent still work very well.


The Adcoms and Brystons are good amps, but they can't handle the low impedance the Kappa 9's will visit. I have two of them here for repair :-)


Cheers
Stefan

[Feanor]

Both the Adcom and the Bryston cannot deliver the current Kappa's need. If you drive them in extended mode, it switches off pretty fast. The Parasound and Vincent still work very well.


The Adcoms and Brystons are good amps, but they can't handle the low impedance the Kappa 9's will visit. I have two of them here for repair :-)


Cheers
Stefan
I'm bemused by this whole topic. If the Kappa 9's are indeed as difficult to drive as Efertheredfish makes them out to be, then I suggest they're more trouble than they're worth, (given the huge variety of great speakers out there).

As ever, it's not just the impedence range but also the volumes that count -- an amp might handle 2 ohms at 20% of rated output but not at 100%. Cooling is a factor too; fans might be necessary.

If one must live with such an impractical speaker and, at the same time, have a limited budget, then consider a good professional amp. E.g. a QSC PLX1802 (http://www.qscaudio.com/products/amps/plx2/plx1802_specifications.htm) that can deliver 900 wpc into 2 ohms.continuously; about US$900.

http://www.qscaudio.com/images/products/plx2/plx1802_front.jpg

[Mr Peabody]

The 9's are, a bear. I don't believe amps like Vincent or regular Parasound deliver more current than Bryston.

[efertheredfish]

The 9's are, a bear. I don't believe amps like Vincent or regular Parasound deliver more current than Bryston.

I had it on the bench and they are able to handle the short musical transiens better and for a longer time. The slew rate seems to be better fitted within the tolearance of the capable current than on the other amps. This is what i measured here in my home.
I also noticed that the caps at the .78 ohm load @ 38 Hz have still enough enegry.

Harnman in Germany tested those amps during the early 90's and they worked pretty well. Measurement and protcols can be ordered via mail from harman in Germany, but only for payment as far as i know.

If you do not believe, its up to you.

No, this loudspeaker isa joy to listen if you pair them right. I never said that Infinitys are cheap. They preformance is beyond most other speakers even the most expensive ones if you power them right

I only know the Bryston 4B and 3 and they don't have the power to drive the Kappa's quite well. The larger models can do that, but I assume they are far over 500$???

Cheers
Stefan

[Raj J]

thanks for your messages and advice folks, no doubt seems like this guy has a dinasour to drive...
which is excatly my point; doesn't have the budget to spend on a good quality amp to drive the kappa's to their true full potential - therefore it will never be a Kappa! and that is my point.
he's better off selling the thing and getting a pair of fine mini-monitors with a sweet tube amp that will give him endless hours of musical perfection, but it seems like musicality is probably not the factor here so forget that!

Manley monoblocks 350 watt tube design, mac amps, or even the big VTL's will drive these babies with ease. solid state I would think Krell's, Pass Labs, ok Threshold for crying out loud, and of course none other than Audio Research - tube or solid state AR will defintely drive Kappa's no sweat.
anything else, forget it! not even interested...
cheers, and have a good one!
RJ

[Panagiotis Melas]

Hello from Greece.

May 2012 be a Prosperous, Healthy, Peaceful and Happy Year for everyone in this community.

This is ny first post and the thread drew my attention, when I was searching for information about the Infinity 9 Kappa speakers impedance.

I am also an owner of an Infinity RS 9 Kappa pair. I purchased these speaker from a hi-end store in Orleans, back in December 1991. I loaded them on a tanker vessel, a ship under my responsibility, when I was working as a sup't engineer in a shipping company. They travelled North Atlantic up to Italy, and from there by truck all the way to Greece. Since then, they have been my reference speakers (together with a pair of Mirage M3-si ones, which are located in a different space).

I tried first to drive them with a Sansui AUX-911DG integrated amplifier, a very fine one (110 WRMS/ch), but it was obviously inadequate for them. Then, I tried a powerful Carver TFM-45 (375 WRMS/ch), but its sound was fairly muddy. Then I obtained a Hafler XL-600 (305 WRMS/ch), which seemed to drive them much better, but still something was missing.

Soon I got a second XL-600 and I hooked both Haflers with bi-amping configuration. The sound became much more open, not because there was more power, but probably because the mid and high frequency sections had their own amplification unit to drive them, ditto with the bass units.

Then I discovered Musical Concepts. I ordered my first modification kit, the PA-1 and I modified one of the XL-600's, leaving the other as it was. I used the modified Hafler alone to drive the Infinities. The sound was indeed bettered. Unfortunately, I had to sell this execellent modified XL-600, which later on turned to be a big mistake. But I couldn't settle.

After about one or two years from that event, the PA-3B Elite kit became available from Musical Concepts. This was a major improvement of the first (and second) generation kits. The Elite kit, except the electronics (boards, transistors, resistors, capacitors, etc.), it also included a pair of toroidal transformers, to replace the original "boxy" transformer in the XL-600. When I found myself again in the US, I ordered that kit and I carried it back home. I modified the remaining Hafler with it and there it was:

A sound revelation with full details and glory!!

I tried the Infinities again with a newer Hafler, the 9500 TransNova (250 WRMS/ch). The TransNova drove them well, but not like the modified XL-600. I settled with the XL-600 since then.

Certainly, I expect that much more expensive units, coming from Krell, ML, Audio Research, McIntosh, Threshold etc. would add a lot to the sound of these speakers, but........we live in hard times and I believe that an afoordable AND good solution, a real "value for money", can be everybody's target.

Good day to all.
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