Infinity Kappa 8.1

[Manuel64]

I put the 8.1's back into duty lastnight. I'm really enjoying these speakers, they so remind me of the day I went to buy a turntable and first heard the CS 3009 in a fellow's garage, it was a life changing moment for me.

In response to okeeteekid and jazzman, i believe i'm understanding the coloration you guys are talking about. While I totally agree that the Ren 90 is the superior speaker for what do we call it "truth" of audio reproduction ? And my componets are probably mid fi at best, and i know many are not fans of the pro audio amps. I believe what i've assembled is fairly good.

The 8.1 to me is the more pleasing speaker, while we all listen on our own terms, I find that 90% of the time I do not critically listen to my music. I push a few buttons and jam getting ready for the day, relaxing fooling around in the house etc.

For that purpose, these are literally perfect ! While I appreciate the attributes of both speakers and feel very lucky to own them both now, a little coloration isn't bad

The 8's and 8.1's are my favorite speakers in the Kappa lines. For most rooms, in my opinion, the 9's are just too big and produce too much bass. In my opinion, the 8.1's are about equal to the CS-3009's. The 3009's may be a bit better for rock, movie soundtracks, and other dynamic music, but the Kappa's are a bit better for jazz and softer stuff. Overall, both speakers are roughly equal. The only thing that I have never liked about the .1 series was the front facing port and the Polydome. Now don't get me wrong, I think Polydomes sound great, but the ones in the Kappa Series have a tendency to go bad over time. I also prefer rear firing ports, but that is a personal preference.

The Polydomes on your 8.1's look to be in truly excellent shape. Congratulations.

By the way, I am a big fan of the Ren's 90's too. A truly great speaker that works in all room sizes. The 90's have a very similar sound signature to the much more expensive Infinities. After messing around with a whole lot a of different Infinities over the years, I've come to believe that the really good ones have a mid bass coupler. This single driver adds a lot of separation and space to the sound signature.

Keep those Polydomes in good condition. Good ones are very hard to find these days.

 

[Bahamayellow]

The 8's and 8.1's are my favorite speakers in the Kappa lines. For most rooms, in my opinion, the 9's are just too big and produce too much bass. In my opinion, the 8.1's are about equal to the CS-3009's. The 3009's may be a bit better for rock, movie soundtracks, and other dynamic music, but the Kappa's are a bit better for jazz and softer stuff. Overall, both speakers are roughly equal. The only thing that I have never liked about the .1 series was the front facing port and the Polydome. Now don't get me wrong, I think Polydomes sound great, but the ones in the Kappa Series have a tendency to go bad over time. I also prefer rear firing ports, but that is a personal preference.

The Polydomes on your 8.1's look to be in truly excellent shape. Congratulations.

By the way, I am a big fan of the Ren's 90's too. A truly great speaker that works in all room sizes. The 90's have a very similar sound signature to the much more expensive Infinities. After messing around with a whole lot a of different Infinities over the years, I've come to believe that the really good ones have a mid bass coupler. This single driver adds a lot of separation and space to the sound signature.

Keep those Polydomes in good condition. Good ones are very hard to find these days.

Are you saying my butts to big in this small room. Lol

 

[7.62]

Nice Bahama !

I'd have to agree on the front facing port, just on look's. I'd much prefer it to be in rear. What I don't understand is why it's even there. I took a quick peek and it's stuffed with 2 kinds of poly material ? really it looks like it's sealed off with the stuff and not a whole lot of air moving past it.

 

[uvafan420]

Nice Bahama !

I'd have to agree on the front facing port, just on look's. I'd much prefer it to be in rear. What I don't understand is why it's even there. I took a quick peek and it's stuffed with 2 kinds of poly material ? really it looks like it's sealed off with the stuff and not a whole lot of air moving past it.

Not sure why Infinity did that with the 8.1 either. The 9.1 is ported to the rear. So strange they did one a different way than the other. But of course they had sound rooms, measuring equipment, etc... So I am sure there was some purpose to the madness.

 

[Manuel64]

The European Kappa lines, the.2's were all ported to the rear. Years back, I had the pleasure of listening to some 8.2's that were brought over from Germany and I recall that they were exactly the same as the 8.1's, except with the port in the rear.

Yeah, the Kappas are pretty stuffed with polyfill. The Crescendos are too. I prefer it that way. The ports work, but it's a much more controlled bass than with an opened port and hollow interior. When I re-foam my speakers, I always add more polyfill - even if it already has some inside. I used to play around a lot with different types of bass control using the ports, using different kinds of plugs and materials, but over the last few years, I just stuff them with polyfill. Rear ports also reflect off the back wall of the room, which I prefer over a port that points at you. But that is a matter of personal taste.

By the way, last year I had my Infinitesimals .2's rebuilt and was surprised that they had very little polyfill in them. Yes, I know that they are very small speakers, but all good quality Infinities, even the small ones that I've seen, are usually stuffed with poly. About the only Infinities that I have seen without much fill are speakers like the SM Series. I guess, less fill means more Boom!!!

 

[jazzmans]

Nice Bahama !

I'd have to agree on the front facing port, just on look's. I'd much prefer it to be in rear. What I don't understand is why it's even there. I took a quick peek and it's stuffed with 2 kinds of poly material ? really it looks like it's sealed off with the stuff and not a whole lot of air moving past it.

because stuffing it with polyfill 'fools' the speaker into acting like it's in a much larger enclosure. play some high db music, and you'll see, a lot of air is being moved through taht port.

I prefer a front port as it lets the speaker interact less with the back wall, then with a rear port.
rip Mr Nudell....

 

[7.62]

I've been screwing around with this DB meter on my Iphone, doubt it's very accurate but it's something to mess with anyway, hey 86db is pretty frickin loud on this thing !

At that level, which was almost more than I could handle, think I was playing Metallica "Whiskey in the Jarrow" IMHO has fantastic drums, NO air was coming out of that port that I could feel on the back of my hand from placed right on the face of the port.

Like uvafan says, I'm sure there was a method to the madness.

And it's been my experience that all of the cresendo line and the 8, 8.1 are all tightly stuffed with polyfill.

I would really like your guy's opinion on spiking these 8.1's. I promised Jazzman, and my wife I wouldn't modify or mess around with these in any way.

BUT.......the rear of the speaker has only little plastic nubs on them, they are deteriorated and broken, almost nothing is left. I have the rear of the speaker sitting on 1/2 mdf blocks. I'd really like to order some 1 1/4....1 1/2 tall adjustable spike set's with pads and expertly install them in the back of the speaker and use the existing holes in the front.

Which means, I have to drill 2 holes in the rear of the speaker, Thus it's modifying them .

So my options are for leveling them, remove the front spikes and put those felt pads underneath, take the front spikes off and just let them sit on the floor, an idea i don't like because the bases can still be damaged, or drill the rear and get them off the floor.

Jazzman, give it to me straight, and I think I know your answer, all opinions are welcome.

 

[Manuel64]

One thing that I forgot to mention about the original polyfill in the speakers. I've seen the same Infinity speaker models filled to different levels from the factory. I believe that this was simply due to the factory using different amounts for different production runs. Polyfill is not expensive, but perhaps this was part of cost cutting on certain production runs. You can get some differences when a speaker is produced for a few years. I've refoamed many Crescendos and Kappas and have seen differences in the same models. Two Kappa 7's that I refoamed come to mind; one set was stuffed completely and the other was only partially filled, having a sizable cavity around the woofer. I've seen the same thing with Crescendos and other Infinities. It's hard to believe that an owner would open up the speaker and take polyfill out, so differences from the factory is probably the answer. Perhaps the production worker simply didn't feel like filling the speaker completely that day.

 

[okeeteekid]

I think the chamber for the mids and mid bass are dacron I don't know if dacron was used to fill the whole speaker cabinet, my epsilon says dacron fill for the woofer.

 

[Manuel64]

I think the chamber for the mids and mid bass are dacron I don't know if dacron was used to fill the whole speaker cabinet, my epsilon says dacron fill for the woofer.

Interesting. Does the Dacron look similar to the white poly that is usually used? I have seen some polyfill that is a bit more like cotton than others around the mids and mid bass. Perhaps a bit denser. If it's white and fluffy, I call it polyfill.

Those Epsilons are pretty pricey, so maybe they used some different fill for those.

 

[okeeteekid]

Interesting. Does the Dacron look similar to the white poly that is usually used? I have seen some polyfill that is a bit more like cotton than others around the mids and mid bass. Perhaps a bit denser. If it's white and fluffy, I call it polyfill.

Those Epsilons are pretty pricey, so maybe they used some different fill for those.

It does look similar but is more coarse looking and feels more coarse to the touch, poly doesn't pull apart as easy as dacron.

 

[Manuel64]

It does look similar but is more coarse looking and feels more coarse to the touch, poly doesn't pull apart as easy as dacron.

I checked it out online and Dacron is a brand name of polyester synthetic fiber. So basically it's a type of poly. If it's the cotton like poly that I've seen mostly around the mids of some speakers, you are right in that it feels courser and maybe a bit thicker. Whenever I saw a different kind of poly, I just figured that Infinity sometimes changes it's suppliers and therefore the poly is not always made by the same company.

 

[slimpikkins]

https://www.aliexpress.com/item/10P...-for-Fender-Ampeg-vox-AH3-AH2/1934781834.html
No drilling needed. I made a couple pair similar to these and like them a lot.

 

[jazzmans]

I think whichever you choose is fine, but those stick on spikes are very interesting.
So, since I was sitting here reading your post, AND Metallica 'Blackened' from ...And Justice for All had just come on, I went over to my Crescendo 3009s, turned the volume up till it was LOUD which to my ears is exactly in the 80s db-wise, and put my hand on the rear port.
No doubt, there was air flow going on due to the kick drum and bass, not a ton, but definitely air flow.

The tapered insert that is the port for the Kappas was designed precisely to controll the 'chuffing' effect from the bass, it's one of the very few places you can see the cost cutting in the Crescendo line vs the Kappas, and that ever widening throat of the kappas does what it says it does very, very, well IMO.
That's my theory on why you couldn't feel much air-flow, anyway, the fill diffracts the airflow and the port tube allows it to escape without building much velocity, which is (again, imo) why some ports 'chuff' and distort the sound.

Remember, a ported speaker is using the rear wave, just delaying it enough to be in phase with the front wave, instead of simply absorbing the entire rear wave, as an acoustic suspension does. any velocity airflow that increases due to cabinet dimensions has got to distort the sound if you think about it.
To truly test, you could scotch tape a piece of paper in front of the port taping only the top, and watch the paper move(as it will) it'll probably take lots of volume, but it'll move.

Example.... (weird example but it'll do)
at EDC this year, my stage, 5, (basspod) when music was playing at 120 db, when the front (finger) pyro went off, (it was placed directly in front of the hanging audio array)

The heat and flames totally changed the sound from the high stacks, it was a very, very odd thing acoustically to hear, like a wide filter was just splitting the highs up, diffracting them.

and, the song is Whisky in the Jar, a traditional that's OLD. Metallicas version is one of my least favorite, but I fell out of love with them decades ago, ever since the napster debackle, and especially after they fired Jason even Though I absolutely adore Trujillos bass playing, (Suicidal Tendancies forever!)

Check out Jerry Garcias version off of Shady Grove, that whole album is absolute magic, as is the Pizza Tapes.

I've been screwing around with this DB meter on my Iphone, doubt it's very accurate but it's something to mess with anyway, hey 86db is pretty frickin loud on this thing !

At that level, which was almost more than I could handle, think I was playing Metallica "Whiskey in the Jarrow" IMHO has fantastic drums, NO air was coming out of that port that I could feel on the back of my hand from placed right on the face of the port.

Like uvafan says, I'm sure there was a method to the madness.

And it's been my experience that all of the cresendo line and the 8, 8.1 are all tightly stuffed with polyfill.

I would really like your guy's opinion on spiking these 8.1's. I promised Jazzman, and my wife I wouldn't modify or mess around with these in any way.

BUT.......the rear of the speaker has only little plastic nubs on them, they are deteriorated and broken, almost nothing is left. I have the rear of the speaker sitting on 1/2 mdf blocks. I'd really like to order some 1 1/4....1 1/2 tall adjustable spike set's with pads and expertly install them in the back of the speaker and use the existing holes in the front.

Which means, I have to drill 2 holes in the rear of the speaker, Thus it's modifying them .

So my options are for leveling them, remove the front spikes and put those felt pads underneath, take the front spikes off and just let them sit on the floor, an idea i don't like because the bases can still be damaged, or drill the rear and get them off the floor.

Jazzman, give it to me straight, and I think I know your answer, all opinions are welcome.

 

[7.62]

slimpikkins, thank you for that recommendation. it's a possibility but I'd like a little adjustability if possible.

I love this stuff, Jazz that's awesome I have never heard that version. alway's learning am I. The difference between the version you posted and Metaliica is this for me, at 4 in the morning when I have to get my ASS out the door and the coffee isn't doing it, their version get's the blood flowing .

The entire cresendo line, 6, 7, 8 and 9 is this, the cabinet is filled with the polyfill. The port is not, and they all fire, vent in the rear. The 8 is sealed but stuffed pretty tightly. The 8.1, or at least this pair has a disk of something and more polyfill below it, IN the port, it's just far enough down you can't see it if the grills are off and your looking at the port.

And as far as stuffing goes, infinity used several types. If you pull the plates off from your 90's midrange emim tunnel, your going to find something that resembles, if it is not wool, very dense material, very densely packed. It amazes me that sound is able to pass through it, but it does.

Actually their should be 2 kinds, the first layer is some sort of polyfill, then behind it up to the back of the driver will be the woolish looking stuff. Same in the 80's.

 

[goodolpg]

Partsexpress has these on sale TODAY, available in 3 or 4 colors I think
https://www.parts-express.com/dayton-audio-iso-4g-gold-isolation-cone-set-4-pcs--240-720

 

[Manuel64]

The tapered insert that is the port for the Kappas was designed precisely to controll the 'chuffing' effect from the bass, it's one of the very few places you can see the cost cutting in the Crescendo line vs the Kappas, and that ever widening throat of the kappas does what it says it does very, very, well IMO.
That's my theory on why you couldn't feel much air-flow, anyway, the fill diffracts the airflow and the port tube allows it to escape without building much velocity, which is (again, imo) why some ports 'chuff' and distort the sound.



Yes, I agree. Infinity did some cost cutting on the ports of the Crescendo line vs. the Kappas. I do think that if the ports would have been located in the front, Infinity would have used the same ports that the Kappas used.

On my own 3009's, the area around the ports were left without polyfill, so that air moved more easily. Since these are my main home theater speakers, that also get a lot of audio use, I have played around with the ports many times. At one time, I completely plugged them and at other times, I would leave them open or partially stuff them. In my opinion, wide open/unstuffed ports do make movie soundtracks better. The bass response is more spread out and more bloated. This makes for a more immersive home theater experience. On the other hand, for listening to audio, less air movement out of the ports is preferable. This tightens up the bass.

I've been using my speakers mostly for audio lately, so I went back and completely stuffed all of my speakers with polyfill. My 3009's sound better than I ever heard them. There is still some air movement from the ports, but while I can hear bass coming out of the ports, I can't really feel much air coming out. I added an Infinity subwoofer to my system that only gets used for movies.

The only speakers that I haven't filled with polyfill are my Infinitesimals. They are very small and have no ports. They are also heavy little suckers, so I am fine with them the way they are. There's not a lot of space inside, as the new components that replaced the original parts, take up more space inside. But I do have some unused poly fill around here, so I may yet fill them.

 

[7.62]

I hate my built in clock, couldn't sleep in if i wanted too. So I'm up trying to get the motivation to replace the heater core in my 4x4 4 runner......ugh.

I'm jamming some classic talking jeads, alan parsons etc. Decided to fire up the turntable with the new to me Little bear T10. Thanks Specman !!!

Put on my Nirvana 180 gram Nevermind album the boy gave me last christmas, he has my 8's. Anyway turned it UP...Way UP. Pulled a piece of paper out of the printer and held it against that port and it is dead still ? I don't know what I'm trying to prove other than that port isn't letting much air out.

Oh, and slimpikkins, the more i look at those spikes the more i'm liking that option. probably going to pull the trigger on a set of 8.

And these speakers Rock

 

[uvafan420]

And these speakers Rock

I know one thing, and I do not need my Krell amp back to even say, my set of Kappa 9.1 SII are not going anywhere.

 

[jazzmans]

I hate my built in clock, couldn't sleep in if i wanted too. So I'm up trying to get the motivation to replace the heater core in my 4x4 4 runner......ugh.

I'm jamming some classic talking jeads, alan parsons etc. Decided to fire up the turntable with the new to me Little bear T10. Thanks Specman !!!

Put on my Nirvana 180 gram Nevermind album the boy gave me last christmas, he has my 8's. Anyway turned it UP...Way UP. Pulled a piece of paper out of the printer and held it against that port and it is dead still ? I don't know what I'm trying to prove other than that port isn't letting much air out.

Oh, and slimpikkins, the more i look at those spikes the more i'm liking that option. probably going to pull the trigger on a set of 8.

And these speakers Rock

tape the paper to the speaker on the top only, letting it hang naturally. That way the tape acts like a hinge. Like I said, the whole point of that tapered port is to keep it from chuffing, but if you hang a piece of paper there and watch it, you'll see some movement. I can't speak for the vinyl, but Nevermind is a terrible master with little bass, btw. it sounds bassy, but that's mostly midrange mid-bass.

Happy T-day, everyone!