Infinity Speaker Choices: RS4 or 7 Kappa

[guscjr]

Need some help folks. I'm looking at possibly buying either a set of RS4 or 7 Kappa locally here in DFW. Don't know if the seller is an AK member, might be. I had wondered why the speakers haven't sold already, but doing some research the last few days I'm figuring 1: people are wanting the taller, bigger RS4b and 2: the replacement midrange in the 7 Kappa are a turn off - which the seller has acknowledged.

So 1: how much difference is their sonically in the RS4 vs the RS4b? I've heard the RS6b, owned the 8 Kappa and the 7 Kappa briefly, the RSb, the RS3b. The 6b stopped me in my tracks listening to them in an audio showroom years ago. RSb (with the old silver EMIT) were startling when I found I could CLEARLY hear the high end from almost a full 180 degrees in front of the other speaker.

2. The 7 Kappa have the M-330 midrange which seems to have negative reviews which is really awful for a $100 each driver. I read that Millersound does a rebuild of the old Kappa Polydomes with excellent results and reading through this post, wonder if there is a tweak outside of rebuilding the crossover network that could remedy the sound of the M-330 driver:
http://audiokarma.org/forums/index.php?threads/kappa-9-adoption.688952/page-2#post-10059952

That link mentions removing some of the damping material behind the driver. Any possibility of that having any change in the sound?

Both pairs of speakers look good and have freshly refoamed woofers. I'm leaning towards the 7 Kappa as they sounded great driven with a 300/wpc Sunfire amp in my apartment about 4 years ago. As far as prices $225 for the RS4, $340 for the 7 Kappa.

 

[chef free]

Kappa 7 was third from the TOTL while the RS4 was the early version of the fourth from the TOTL. I haven't heard either but I have heard their bigger siblings and I like the Kappa series better.

 

[swechsler]

Yeah, I'd go with the Kappas as well, assuming that the Polydomes are in good shape (otherwise budget another $100 each for repair). While the tweeters are essentially identical, the woofers improved in the time between the two models.

 

[goodolpg]

If you choose the Kappas and the polydomes do need repair, MillerSound will not disappoint.
Great people, great service.

 

[guscjr]

Just got in from work.... The Kappas have new foam on the woofers and new M-330 replacement drivers. I was wondering if there is anyone who has installed them and perhaps changed their opinion after using them for awhile. If all goes as planned, I'm to check them out in the morning. The pics show one very nice looking set of cabinets too.

 

[Bahamayellow]

Big fan of the Kappa line hope it sounds great for you. Let us know what u think and post pics if u get them.

 

[jazzmans]

I'm also a fan of the kappa line, but I like my RS 4b's just as much as my kappa 7.1s

 

[guscjr]

Considering the condition of the speakers and our conversations, I'm going to buy them. Postponed meeting today due to laziness and a work deadline for tomorrow morning. DC270 knows the seller and has done business with him. He does have one original Polydome midrange so my plan is to buy them as-is and look towards having the originals rebuilt from Millersound as has been suggested elsewhere here maybe with tax refund money. The other speakers are RS4 not RS4b. I'm not sure how great a difference in sound there is, but the RS4b was a nicely balanced speaker and had that 'just right' size to fit anywhere and look great too. My prior experience with the 7 Kappa was with a Sunfire 300/wpc amp and that combo was fantastic with striking dynamics and realism at modest levels in my old apartment.

 

[guscjr]

Okay.... well I spent about 30 - 45 minutes listening to the 7s in comparison to some RS3 - an original mirror image pair with a 5 (6?)" polypropylene midrange and polypropylene 8" woofers. The RS3 stand about 2 feet taller with the midrange and tweeter very much unaffected by furniture. They were place in the corners of the room for bass reinforcement with the 7 Kappas center about 3 feet apart; it was a small listening room. The seller had a Sony ES9000 preamp/processor, Pioneer CD player and an Onkyo M-504 amp for electronics, flat 2-channel stereo playback from the preamp. Now this again was a small room with a large recliner and not much else, vinyl/plastic blinds and carpet on the floor. A clap of my hands confirmed it was going to yield a bright sound.

I brought 3 of my own CDs for auditioning the speakers: Stanley Clarke 'Hideaway', Rachelle Ferrell 'Rachelle Ferrell', and Osamu Kitajima 'The Source' (find this just for the 25+ minute opening track 'Heavensent'). Chase - the seller - likes soundtracks primarily and instrumental music in general. He played a couple of tracks which were of a classical nature with strong percussion and brass. The RS3 sounded great, open, natural with no boominess despite being in the corners. Switching to the Kappa 7, the sound was close, maybe not quite as open but the bass was about the same if not a bit deeper. We were both standing and I don't know how much of a sonic difference there would have been sitting.

We switched to my CDs and the first test I wanted was how the guitars on the opening track of Hideaway would sound. In a word, good, very good in fact. About a third of the way into the song, there is a hard plucked phrase that is the highlight of the song and that came across very fine. We both were smiling as I told him that was what I was waiting to hear. We played 'Heavensent' from 'The Source' next and I told Chase to sit down and give a listen. I think he was a bit surprised at just how good the Kappas sounded. There's about a 3 to 5 minute opening harp solo followed by acoustic piano then dual guitars come in, one left, one right, playing strummed chords. I've heard this song several times and there was little too fault from my end. Loud piano notes didn't break up or sound irritating though we did respect the fact the room was small and the volume was just modestly loud.

I paid half down for the speakers and Chase has already taken the ad down off CL. Without another pair of 7 Kappa to have for an A-B comparison, I can't say just how much difference there is in the sound. But given the drivers are just maybe 8 months old and the woofer foam also and the fact that the cabinets have only minor blemishes and most of those to the rear corners, I think my $340 will be well spent. I found out he also has one of the original Polydome K drivers and dc270 might have the other one. One other thing was confirmed for me: the big Infinity speakers need big amps and when they get them, they open up and sing.

I'll post pics when I actually bring them home.

 

[guscjr]

 

[guscjr]

 

[guscjr]

Had them set up since Thursday. Rubbed down with Old English lemon oil polish. The right speaker has a very slight water stain on top. Other than that they are in good shape with very few blemishes. Fresh foam on the woofers and the new replacement drivers were just about the seller's asking price and I think the speakers are worth the investment.

And I'll tell you right now if there's one thing I have NO complaints about, it is the bass performance - clean, deep, and real tones. Plucked string bass is light and tight right up into the upper notes. I did detect a bit of an anomaly with electric guitar tones being a bit too 'warm', if that's the right word. So the midrange/upper bass blending is where I'll keep tweaking the settings. It's about as good as I can get right now and has been enjoyable on a wide range of music including classical as a test of a variety of instruments and percussion.

But hey, remember those little things called equalizers? You can find them at bargain prices everywhere now, even the 31 and 15 band models. I know you can really make a mess of things if you aren't careful, but that might be my next step with a minor tweak on the upper end, the bass (deep 30hz range), and the lower midrange.

 

[goodolpg]

Sounds like all is well.
Congrats!

 

[guscjr]

I'm going to follow the thread about the new 4-ohm Polydome replacement midrange from Madisound to see what the reviews are on it. It's not cheap either, but if it's a better match, I might have to save up for it.