Infinity kappa 8 verses RS 2.5 and RS IIIB??

geph0007

AK Member
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What would I notice sound wise if I went from the RSIIB or RS 2.5 to the Kappa 8. That would be an original Kappa 8? Thanks
 
The kappa 8 has excelent bass, its deep, tight and fast. The Polygraph can sound a little like someone hitting a plastic bottle if not set up properly. The Polydome is open and presents a large sound stage and blends with the Emit seamlessly which produces highs that are airy and smooth however can be fatiguing if not placed out from the wall or in to small of a room. In comparison the RSIIA/B will have a much better midrange in general; soundstage, transparency, pretty much in every way; however the K8s have a flatter/smoother midrange when compared to the RS2.5. The Kappa 8s need less space than the other two and can sound in smaller rooms. K8s are also MUCH harder to drive and having the proper gear upstream makes a dramatic difference. The bass I think is a little tighter and faster than than the RSIIA/B, but they don't get quite as low (close though).The k8s have a very different sound in comparison, mostly because you would be going from planar midranges to dome. If you have RSIIA/B or RS2.5s and like them make sure you spend some time demoing some kappa8s to make sure its what you want. They are excelent and I think make great Home Theatre speaker as well.
 
2.5's are orders of magnitude better. You don't see any Polydomes on an Infinity IRS system do you? 2.5's were a scaled down version of the 4.5, which was an attempt to make the best speaker in the world. The Kappa 8 is one of a multitude of mass produced speakers that came after Infinity made it big. EMIM's really are something special.
 
I have heard/owned 2.5's, II's, IIb's, III's, kappa 9,8,6, QLS 1's, and infinitesimal .1/.2's and i can pretty much agree with musicman95. I never have heard the IIIb's, but if I had to choose between the 3 you listed, i would say go for the Kappa 8's (if you have proper amps for them!) The original kappa series is so much more forgiving compared to anything that has an EMIM. Don't get me wrong, my IIb's sound freaking amazing if not better than k9's for single vocalists, jazz, and classical, but my my kappa 9's are able to play ANY type of music and still sound beyond words! There is no comparison between the kappa 8's and 2.5's when it comes to bass. The 8's hit lower and much louder than the watkins woofers, and they are more fuller sounding (ie: you can feel the bass). EMIM's are much faster and a little more accurate... but i always tend to listen to my kappa 9's more. Just my 2 cents.
 
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2.5's are orders of magnitude better. You don't see any Polydomes on an Infinity IRS system do you? 2.5's were a scaled down version of the 4.5, which was an attempt to make the best speaker in the world. The Kappa 8 is one of a multitude of mass produced speakers that came after Infinity made it big. EMIM's really are something special.

EMIM's ARE something special and i would never trade my IIb's for anything (maybe for something irs later on), but i'd have to disagree with them being 'better' than a polydome. They're definitely different, but not necessary better. Before owning kappa 9's, i had always thought that polydomes would never stack up to an EMIM, but they do and they sound pretty darn good. I will agree however that EMIM's are a little more accurate and faster.
 
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I have seen pro reviews on the 4.5 and they had issues with it. I hear the same issues on the 2.5. Lower midrange/upper bass. Good points and bad points. I now have the Kappa 8s and will do a proper head to head. My first impression is the 8 is more open and airy I use Analysis plus oval 9 wire. I have the terminals inside the 2.5 tied together so I do not need jumpers I HATE JUMPERS. The 8 is harder to do that on so I put in Anti Cable jumpers for the junk gold straps. By using the solid core Anti cable jumpers the sound of the 8 became way more focused (as solid cores tend to do) and the images sharper very very much like the 2.5 is because of the EMMs. With the gold straps the 8 is warmer and more blurred /softer image outlines.
 
The pro review everyone talks about being cridical of the rs4.5 midrange went on to say they were the best full range dynamic system they knew of and remained in their reference system....

"So, the 4.5 isn't perfect yet. So, some other, cheaper, systems do a better job with trombones and cellos than the 4.5. It is still one of the best speaker systems available today, regardless of cost—one that is quite capable of making most instruments sound palpably alive and just as gorgeously rich and smooth as they do in a live situation. Perhaps we are making too much of its one, really minor shortcoming, but much music does lose some of its dramatic impact because of that shortcoming. Despite it, we are adopting the RS-4.5 as our reference test system simply because it is now the best full-range dynamic system we know of (and is thus ideal for power-amplifier testing), and because—all cavils aside—it does everything else so blessedly well. It has been added to our "Recommended Components" list in Class A, with that one little reservation."
Read more at http://www.stereophile.com/content/infinity-rs-45-loudspeaker-system-jgh-returns#MF9gbs3Yck0MOkvm.99
 
I have not been able to find a pair of Kappa 8 or 9, so I cannot really compare them against the RS-4.5. I do have a pair of kappa-7 but that is no real comparison, both the 2.5s and 4.5s are far superior. I could never really notice an issue with midbase in my RS-4.5 (but probaly Im not competent as a listener to spot it). When I updated the EMIMs in the 4.5s, it seemed to me that the whole speakers became a bit smoother so perhaps the hole gets filled in with the EMIMs. Compared to the 2.5s the 4.5s seem to give the EMIMs a much easier time as there was far less rippling on the traces with the 4.5s c/w their smaller relatives. I still have the original EMIMs from mine as spares and they look perfect. It seems to me that the EMIMS may be around for a longer time than the Polydomes and seem easier to obtain - Im sure I have several lifetimes worth of EMIMs hanging about but only 1 spare set of poydomes that I have sealed up well out of any light (which may not help much in any case).

The RS-4.5s also sound more impressive than the RS-2.5 by quite a lot. I don't biamp and have not needed to use the external crossover, just run a really large single amp. They take up rather a lot of space and have low WAF, so they have been banished from the main living area and I get to have a large downstairs music room/study/office/library/cave well out of the way to keep them. The other problem is that they collect dust at a huge rate and the grilles are incredibly fragile.
 
That is not the review I am talking about and reviews are not the end all be all anyway so no big deal . I have the 2.5 and 8 and will compare FYI that extended switch is a bit much on the 8s.
 
For sure the reviews are not the end all but when read tend to get repeated and embellished. This "hole" in the midrange of the rs2.5 and 4.5 if never written about may have never been heard by everyone and they would just simply enjoy their speakers.

Tube reviews are the worst for this. One well known audiophile reviews a tube and "hears" some virtue or flaw and everyone jumps on the band wagon trashing or praising said tube. Next thing you know the tube prices are going through the roof or the "inferior" tube is no longer made making reasonably priced replacements even more hard to find.

For the rs2.5 and 8 kappa I'd say if either were near me and I was in the market I buy them. But for one to replace the other is a toss up imho. Wait for something further up the chain for replacement. Rs1, kappa9 rs4.5, and so on.
Jim
 
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Anyone out there know who can upgrade the capacitors on Kappa 8 and Kappa 9 crossovers? Is there a vintage infinity specialist out there somewhere? Please be in touch.

Thanks!
Brett
www.brettmc.com
 
Hey Brett, that's a tuff one. Most guys will do it themselves. Are you having a problem? I'm sure the guys here could help you if you would wish to take them apart yourself. Hardest part might be getting the xo apart as it is a circuit board and not point to point...
 
Old but still I had every single kappa out there series I and II, and also the rs1b (14 emims)

Just buy a magnepan with a pair of subs it destroys anything emim hands down at a fraction of the cost.

My time with the (restored) rs1b was anything but great. The emims got taxed way to easy , they definitely didn't do what my magnepan Tympani I did at a fraction of the cost.

As far as kappas goes, the Cary christie 8.1 exceeds my old nudells k8. Especially on the upper end and mid range. The mid coupler in the 8.1 and 9.2 are superior over the older polygraphs. The same cone couplers are used in the ren90 and sigma and such. So no surprise there that it sound just a bit more dynamic.

In short. Not a huge emim fan especially not after owning maggies. I run my kappas all day long with 0 fatique these days. I think emims are a very subpar version of what a planar driver is supposed to be

To even reinforce that , nudell himself favored the LEMIM over his emims due to the size of the driver itself. Which is definitely a big thing with planar drivers. I had a good amount of time with the IRS beta (friend of mine owned two sets)

To me the best infinity I've heard to date hands down. But way beyond my system and budget ..
 
Old but still I had every single kappa out there series I and II, and also the rs1b (14 emims)

Just buy a magnepan with a pair of subs it destroys anything emim hands down at a fraction of the cost.

My time with the (restored) rs1b was anything but great. The emims got taxed way to easy , they definitely didn't do what my magnepan Tympani I did at a fraction of the cost.

As far as kappas goes, the Cary christie 8.1 exceeds my old nudells k8. Especially on the upper end and mid range. The mid coupler in the 8.1 and 9.2 are superior over the older polygraphs. The same cone couplers are used in the ren90 and sigma and such. So no surprise there that it sound just a bit more dynamic.

In short. Not a huge emim fan especially not after owning maggies. I run my kappas all day long with 0 fatique these days. I think emims are a very subpar version of what a planar driver is supposed to be

To even reinforce that , nudell himself favored the LEMIM over his emims due to the size of the driver itself. Which is definitely a big thing with planar drivers. I had a good amount of time with the IRS beta (friend of mine owned two sets)

To me the best infinity I've heard to date hands down. But way beyond my system and budget ..
disagree. the IRS Delta/Gammas easily bested my maggies, even with Fathom and M&K subwoofers. There's something about dual 12" woofs in each cabinet that just can't be matched.

I am a huge fan of magnepan, but the delta/gammas were better in every way.
 
Yes, but that Magnepan ribbon...I mean, I love the EMIT, but the 6' ribbon is something else.
the only true maggie ribbon model I have is the 2.5R, and there's a big difference in sound between the ribbon and the rest of the speaker. to my ears. (don't hate me!) the 1.6QR is a more coherent speaker, with wider frequency response.

now if I owned a pair of 3.7........
 
disagree. the IRS Delta/Gammas easily bested my maggies, even with Fathom and M&K subwoofers. There's something about dual 12" woofs in each cabinet that just can't be matched.

I am a huge fan of magnepan, but the delta/gammas were better in every way.
I'd take a Tympani 1 with subs all day long over them easily . Hands down bested the rs1b with ease way better mid range it's not even in the same league .

At nearly 6ft tall line array dipole drivers vs what infinity has to offer, not even the IRS beta (by far even over the IRS v I've heard) I preffered the lemims and to me definitely leaps the emims.

We went over to the Tympani....it's not even close. The mgIIIa same story the true ribbon bested the emits in clarity and definition. The midrange of the mgIIIa was for me lackluster.

The mg 2.5q was fantastic, way better midrange than anything emim loaded including my renaissance. It's again , not even close with the size the maggies could project midrange in a room. I never heard any gap between the drivers (that I did have with the mgIIIa, I absolutely could not listen to them)

Not sure how much space you have to play with but I totally experienced it differently. I had pretty much every mg model and Tympani out there.

The issues I had with maggies and that's why I totally prefer my kappas.

It's not a complete full range system, you will need subs and you will need space. My space could house the Tympani 6x4 stature. But that doesn't take away they are buttugly. And off axis response is just horrible. So we went back to cones with definitely more low end fortitude and no need for subs .

Kappas are definitely not the most defined speakers they color. But to me that equates to a more forgiving speaker overall speaking.

It's very situational I'd say
 
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