Infinity Kappa 5.1 Series II woofer replacement

[slawaguznow]

Any suggestions on which woofers I can use to replace the original ones with?
The original ones have 4 ohm resistance, 90db sensitivity, crossed at 350 Hz. The internal volume is about 25 liters
I'm thinking of using Dayton RS225-4, which has similar parameters.

[johnnyrichards]

I would scour eBay for a replacement, or have the originals repaired.

[johnastockman]

Any suggestions on which woofers I can use to replace the original ones with?
The original ones have 4 ohm resistance, 90db sensitivity, crossed at 350 Hz. The internal volume is about 25 liters
I'm thinking of using Dayton RS225-4, which has similar parameters.

An original woofer or yours, repaired, is the only way to preserve the SQ that you're familiar with...if you're happy with how they sound in their stock form. Unfortunately, there's too many variables at work here, much more than matching T/S parameters and specs so it will work in your enclosure. The XO is a big consideration. Trying to get an aftermarket woofer to work in the box could be done, but even if you can get a match on the specs, the XO that's in there now won't work. Which leads to worse SQ than you have now. Are the originals damaged or are you just looking to improve the current SQ? To improve the SQ, you'll need a XO that's specifically designed for your replacement driver(s). The stock XO that's in there now is minimilist at best. Manufacturers have to think about cost-of-manufacture and many compromises are made, mostly with the stuff you can't see, like the XO and cabinet construction. They use the least amount of parts possible. Some just run the woofer full-range, with no XO components, or just a single inductor. You could just try to match up the specs and slap one in there, but IME, this leads to a poorer SQ than what you had before. The original XO, what there is of one, is designed to work with the stock drivers. No easy fix here...but if you'd like a better explanation, Paul has a couple of write-ups that can tell you why this doesn't work well:

http://undefinition.googlepages.com/diy

The "Getting Started", "MFAQ's Pt. I & II" and "More MFAQ's" go into more detail. If you have any more ?'s, feel free to ask, as there isn't really any dumb questions. I had a ton of 'em when I first showed up here over 9 years ago asking the same things. If you're after better SQ, then a DIY design with a specific-to-the-drivers XO can work in the Infinity enclosures. I've done this many times, taking a commercial speaker, adding some internal bracing (which are not in these types of retail speakers) and making a new baffle to fit over the old one to house the new drivers. Sounds like a lot of work, especially if you don't have a shop and tools. But it's really the only way to "improve" on the SQ of the original.

John A.

[kevinr]

I bought the Parts Express re foam kit for Infinity woofers a while back and it didn't fit my Infinity 10's quite right . Plus the Infinity woofers had a hard tough plastic shell that was non removeable without tools and brute force . Seemed like a lot of work so I returned the refoam kit and bought 2 new woofers instead .

[cpcarter]

I agree that finding a replacement driver is hit and miss. If it's just the surrounds then you can just refoam them. I refoamed the 12" woofers in my Kappa 7's and was very happy with the results. SQ was back to original. I made sure to get the kits made specifically for the Infinitys with the right lip angle and the right glue for that Carbon Fiber or Kevlar cone material. Not familiar with the 5.1 but get the right kits and you'll be back to good-as-new.
Good luck!
CC

[philiparcario]

orangecounty speaker will be your best bet for repair. here is the link



http://www.speakerrepair.com/

send them an email and ask if they can do them

[cpcarter]

Just a quick correction. The woofer cones were injection molded graphite not carbon fiber. Still pretty high tech for 1989. The woofs were cast frames too. These were the Infinity Reference Standard 7 Kappa model. Kind of their flagship series at the time

John A. I agree with your comment on most retail speakers but the Infinity 7 Kappa x-overs were well designed and used quality components. Solen and Wonder caps, Air core coils etc and the cabinets were pretty substantial too. I'll try to attach the data sheet.
CC

[Wolf]

Just a quick correction. The woofer cones were injection molded graphite not carbon fiber. Still pretty high tech for 1989. The woofs were cast frames too. These were the Infinity Reference Standard 7 Kappa model. Kind of their flagship series at the time

John A. I agree with your comment on most retail speakers but the Infinity 7 Kappa x-overs were well designed and used quality components. Solen and Wonder caps, Air core coils etc and the cabinets were pretty substantial too. I'll try to attach the data sheet.
CC

Alright- what are the diodes for? They are opposed I assume to operate bipolarly for AC passage, but what is it they are doing?
Later,
Wolf