Need some help: Inherited kappa 6.1 series ii

Hi guys, I'm new here and came seeking advice about a pair of infinity kappa 6.1 series ii's I inherited. I am an audiophile novice so please bear with me.

There's quite a few problems and I guess I'll just list them, I'm not totally sure if it's an amp/receiver problem or a problem with the speakers themselves:

-so one of the polydome's is busted: the dome itself has a small tear and the metal mesh behind it is bent.
-both woofers need re-foaming which I've ordered and should be doing this weekend.
-one woofer seems misaligned, it "scratches" when i push it in. i saw a guide about how to realign the woofer so i will do that when refoaming unless advised not to.

-along with the kappa's I inherited a harmon kardon festival 500 (60wpc) which they're currently hooked up to. the left channel doesn't seem to work unless it's a very loud moment (in a movie for example). otherwise it kind of "crackles". not sure how to describe it better! however it doesnt seem to be a speaker issue because when i swap the speakers the same issue persists on the "new" speaker.

i've unscrewed the individual speakers and everything looks OK (aside from the busted polydome and the woofer issues), but i am a 100% novice so i am taking that with a grain of salt. my electrical experience has been building computers, i have no experience with speakers or magnetic components.

i don't know the best way to proceed aside from refoaming and realigning the woofers and am looking for advice...i will probably need a new amp i suppose? my budget isn't huge (~500 usd) so i am looking at the adcom gfa-555ii which i saw recommended here on AK.

any help is much, much appreciated! i want to bring these babies to life!

Welcome to AK. Great speakers. The polydome issue can be tackled two ways. Send them somewhere to be fixed. (you will want to send both) or buy another used one off of ebay. The latter will most likely be cheaper.

The crackle in the one channel is most likely a dirty volume knob or swith. While it's playing wiggle each knob and switch and I bet you find it. Then remove the cover and clean all switches with some contact cleaner. If that doesn't do it then you will need to have it serviced.

The rubbing woofer may be fine. Can you press on it and find the sweet spot where there is no rubbing? If no the dust cover will need to come off so you can look into the coil and magnet assembly. If the speaker was over driven the coil may be rinkled. If you are lucky you can flatten the rinkles out with a round object like a sharpie pen so theres no more rubbing.
Jim

for speaker repair :

Bill at

Millersound
1422 Taylor Rd
Lansdale PA 19446-1531

he has done work for a lot of people on this site...good guy..

@Jim:

Thank you for the helpful reply.
What worries me about the polydome is the busted metallic mesh. I don't see how this is repair-able. Might have to get one from ebay as you mention.

I will check the contacts and switches today as you suggest and post the results this evening.

Edit: I cleaned the back contacts on the speakers and still some crackling at high volumes on the EMIT-Rs. It doesn't seem to be a huge issue at the moment as they play fine and you can barely hear it when going between songs etc.

More worrisome are the woofers as I was incorrect in my initial assessment:

For the scratchy woofer, there is a "sweet spot" if I apply slight upwards pressure when moving it. I was planning on following the instructions here (http://www.goodhifi.com/Refoam Instructions/Refoam manual.htm) to refoam and re-align the woofer.

The other woofer, while it seems to be aligned correctly, just does not work. I tried both speakers on both channels, the one "scratchy" woofer works fine, the other woofer does not work at all. Not sure if it's the woofer or the crossover, though.

@Bkphoto:

Thank you for Millersound's information! Their name came up a few times in my reading of this forum before I posted. I will certainly use them if needed.

Measure the "bad" woofers resistance across the two speaker terminals on the woofer with a multi meter.
The number (or no number at all) will help with troubleshooting.

@goodolpg

I will get a multimeter and report back. Cheers!

Sounds like you may need a woofer too. They do come up on ebay. That 8" woofer is in a number of 90's Infinity speakers. Reference, Crescendo, Kappa... They may differ slightly between the models. Maybe someone can chime in.
Jim

TY for the tip Jim.

Hi guys, thanks for all the help thus far. I checked the woofer with the multimeter and surprisingly it read 3.5 ohms of resistance. I guess this means it's the crossover causing the issue?

The Harman might have dirty relay contacts causing the cracking, but it can be a million things including the old caps.

Use the test tone method for re-aligning the woofer when refoaming. There's plenty of videos and info regarding this. You obviously don't want to cut out the dustcap to shim it since you probably won't find another. I've always had good results using the test tone method. If you're not comfortable doing repairs you might want to just send the woofers out to a pro for a refoam and it's not too expensive.

If you move the non-operational woofer when the music is playing, does it work when you press it in? Strange it reads a resistance, wouldn't expect the x-over to have a failure like that.

Regarding the polydome, you're obviously going to need a replacement. From what you described it probably still works despite the damage so you could get the woofers repaired and see how they work in the meantime.

@ jindra

thank you for the response. the non-operational woofer does not work if i press it in when music is playing.

i will look into youtube videos about the test tone method to realign the woofer and report back. i love doing my own repairs so i will probably attempt it myself unless it seems too damaging if i make a mistake.

the polydome works so i will put that on the back-burner until i have the woofer issue fixed! will most likely have to get another one.

If the dead woofer is basically a write off and you need a replacement, I would encourage you to take it apart. You might be able to find where the tinsel wire burned up fairly easily. If the foam is already disintegrating around the cone all you need to do to pull the whole cone and VC assembly out would be to separate the spider from the voice coil in the middle. To really dig in, I'd wet the gap around the dustcap with some 70% alcohol to soften the glue and separate carefully with a razor blade or something similar. Alcohol will blemish the glossy plastic of the IMG woofer though so be careful, but if its a junk woofer who cares right? If you do rescue it though it would be nice to keep it in good condition.

I've had to just add some solder to these leads and repaired some woofers before:


This is a Technics Tweeter that had the tinsel wire burn, you can sort of see where I soldered the pieces back together.


I'd wager it's fixable but it might cost you some grey hairs.

I would remove the woofer that does not make any sound and attach it directly to your speaker wires from the back of your amp to see if it makes any sound, if it makes sound check for any loose wires coming from the crossover board and also the wires that attach the woofer section of the crossover to the speaker terminals on the back of the speaker cabinet, check for dry solder joints on the crossover board and any loose parts on the crossover board, the crossover section for the woofer has only 3 parts, L5 2.50mH coil, L6 0.70mH coil, C7 140.0 uF NPE capacitor, I doubt any of those parts are bad but you never know, most likely a loose part or dry solder joint.

okeeteekid said:

I would remove the woofer that does not make any sound and attach it directly to your speaker wires from the back of your amp to see if it makes any sound, if it makes sound check for any loose wires coming from the crossover board and also the wires that attach the woofer section of the crossover to the speaker terminals on the back of the speaker cabinet, check for dry solder joints on the crossover board and any loose parts on the crossover board, the crossover section for the woofer has only 3 parts, L5 2.50mH coil, L6 0.70mH coil, C7 140.0 uF NPE capacitor, I doubt any of those parts are bad but you never know, most likely a loose part or dry solder joint.

Click to expand...

I forgot OP mentioned the woofer was reading a resistance. DISREGARD my advice on tearing the woofer apart UNTIL you isolate the issue to the woofer and it's 100% not the x-over!

WOW thank you both for your advice, jindra for the excellent pictures and okeeteekid for your advice regarding the crossover.

I will spend the next day or so investigating.

I believe these woofer connectors are soldered in place so that will be hassle to undo and then redo. I think my two options (taken from this thread here, thank you Talk_Louder: http://www.audiokarma.org/forums/showthread.php?t=638813) are to unsolder the spade connectors and then re-solder once the woofers are refoamed/aligned/inspected, or to clip the wires connecting the woofer to the crossover and then use a butt splice to reconnect afterwards.

Boy I am learning new techniques!

No problem buddy. Not sure if you've come across my threads about these speakers yet, I deal with the polydomes a bit more though since I never really had issues with the woofers:

http://www.audiokarma.org/forums/showthread.php?t=614034
http://www.audiokarma.org/forums/showthread.php?t=630878

okeeteekid said:

I would remove the woofer that does not make any sound and attach it directly to your speaker wires from the back of your amp to see if it makes any sound, if it makes sound check for any loose wires coming from the crossover board and also the wires that attach the woofer section of the crossover to the speaker terminals on the back of the speaker cabinet, check for dry solder joints on the crossover board and any loose parts on the crossover board, the crossover section for the woofer has only 3 parts, L5 2.50mH coil, L6 0.70mH coil, C7 140.0 uF NPE capacitor, I doubt any of those parts are bad but you never know, most likely a loose part or dry solder joint.

Click to expand...

^ I was going to suggest "hot wiring" the woofer too. A little more difficult since it is soldered to the wiring, but can be tried when you unsolder for the refoaming process.
You can do it with LOW volume, bass turned down, for just long enough to see if it produces sound.
Based on the ohm reading it "should" work.
Maybe the voice coil is seized?

Hi guys,

Sorry for such a late reply, life has been busy.

So today I spent the day re-foaming the non-responsive woofer. While I had it out of the frame I also "hot wired" it per goodolpg above. Good news, it worked perfectly.

So the woofer apparently is not the issue. I examined the cords and connections from the woofer to the crossover and those appear in good shape as well.

I suppose the problem must be in the crossover!

I bought 2 pairs of Kappa 6.1s recently and one of the pairs had a bad crossover. Actually looked like something fried all the wiring because it was all discolored. I never found out what the issue was. The cabinet with the bad crossover was actually the nicest of the 4 so I ended up pulling out the wiring and crossover from a good unit and placed it into the nicer cabinet. It's an easy job. Took about 5 minutes.

The weird part is that nothing on the crossover looks obviously out of sorts. I'm going to compare it to the other crossover tonight and see if there's a glaring difference.