Do these dented woofers need to be replaced?

[jimroge]

Hi,
Looking for some expert opinions on this. Infinity Primus 360, bought knowing I may need to do some repairs. Two woofers are dented a bit, one worse then the other. The woofers are said to extend up to around 350 Hz. Do you think it will be noticeable? Is it possible to repair, by say trying to bend it back? Looks like some parts are available online or could buy a 160 to donate woofers. Thoughts?

 

[Mikig]

I've seen crushed and damaged domes, but a driver's cone this dented, almost never. What happened to it?

 

[kemmler3D]

Have you tried listening to them yet? I think the main thing to worry about is damaged voice coils, which I think could happen here.

 

[DVDdoug]

Do you think it will be noticeable?

You tell us. If the sound is damaged it will probably sound terrible.

Is it possible to repair, by say trying to bend it back?

No. There are specialty shops that "recone" speakers but the result probably wouldn't be identical. I think those shops are good, but that seems to be a unique cone so it's hard to know how well they could match the characteristics.

 

[jcarys]

What DVDdoug said. Your ears will tell you if there is a problem. If you want to got further you could test them with frequency sweeps and check the spectrum response in the woofer region. My guess is that you'll want to replace the woofers. You should be able to find parts listed at Ebay or other sellers.

 

[Vini darko]

Run a slow frequency sweep on each speaker and listen for anything nasty coming from the woofers. They may be fine.

 

[Old_School_Brad]

Hmm. The cones are made of anodized aluminum, which makes me concerned about the force required to cause such extreme deformation in the first one -not just dented but significantly misshapen. I wouldn’t be surprised if this had offset the voice coil.

Does it make any unusual noises when you gently push the cone inward?

As others have suggested, I’d recommend running slow frequency sweeps at gradually increasing volume and listening carefully for any odd sounds.

 

[EERecordist]

Once it is deformed, it is possible that there will be unwanted resonances. Those could lead to increased harmonic distortion. Those are decent speakers, worth reconing, or getting a good used replacement driver if the price is reasonable.

 

[terryforsythe]

Those are decent speakers, worth reconing if the price is reasonable.

IF the drivers need to be replaced (i.e., if the distortion is audible), the OP is better off trying to find the original drivers. That can be hit or miss, but worth a try.

The problem with reconing is that if the shop cannot get their hands on the original cone, the driver characteristics probably will change. Especially important is maintining the original cone mass so that the Thiele-Small parameters and efficiency are not changed. Also, the frequency response characteristics should not be changed, but different cones have different characteristics (e.g., breakup modes, etc.)

 

[jimroge]

Have you tried listening to them yet? I think the main thing to worry about is damaged voice coils, which I think could happen here.

Just a little, nothing serious yet, as others have said I will try a low frequency sweep and see if I hear anything nasty.

 

[jimroge]

I've seen crushed and damaged domes, but a driver's cone this dented, almost never. What happened to it?

Don't know bought cheap figuring I could fix if needed

 

[jimroge]

What DVDdoug said. Your ears will tell you if there is a problem. If you want to got further you could test them with frequency sweeps and check the spectrum response in the woofer region. My guess is that you'll want to replace the woofers. You should be able to find parts listed at Ebay or other sellers.

Any other suggestions besides EBay?

 

[Heinrich]

Hi,
Looking for some expert opinions on this. Infinity Primus 360, bought knowing I may need to do some repairs. Two woofers are dented a bit, one worse then the other. The woofers are said to extend up to around 350 Hz. Do you think it will be noticeable? Is it possible to repair, by say trying to bend it back? Looks like some parts are available online or could buy a 160 to donate woofers. Thoughts?

Looks more like self-destruct from too much excursion. May be that the voice coils got de-centered. A sweep will tell as others already mentioned. In case you want to get into terms with old speakers, an investment in a microphone might be worthwhile.

 

[jcarys]

Any other suggestions besides EBay?

If you find out that there's audible damage then I would recommend you take them to a professional speaker repair shop. If you are handy, you could get replacements and swap them yourself. But others have suggested there could be issues with the voice coils. Personally I don't have the background to check all failure points in a speaker. In terms of replacements, I would just do a web search. There are tons of places that sell replacement or used parts.

 

[Roland68]

Hi,
Looking for some expert opinions on this. Infinity Primus 360, bought knowing I may need to do some repairs. Two woofers are dented a bit, one worse then the other. The woofers are said to extend up to around 350 Hz. Do you think it will be noticeable? Is it possible to repair, by say trying to bend it back? Looks like some parts are available online or could buy a 160 to donate woofers. Thoughts?

Do not bend it back under any circumstances.
Check whether the voice coil "scratches" when moved. To do this, gently press on the center of the cone, only as far as the cone would move, of course.

What material are the cones made of?

 

[jimroge]

Do not bend it back under any circumstances.
Check whether the voice coil "scratches" when moved. To do this, gently press on the center of the cone, only as far as the cone would move, of course.

What material are the cones made of?

Not sure someone said aluminum.

 

[jimroge]

Well it gets worse , in listening and sweeping one of the tweeters is very distorted and probably needs replacing too, if it's not the crossover. I have a nice little project here!

 

[Heinrich]

Well it gets worse , in listening and sweeping one of the tweeters is very distorted and probably needs replacing too, if it's not the crossover. I have a nice little project here!

Party time! Maybe those have seen some misuse? Good luck, I've been there myself ...

 

[terryforsythe]

one of the tweeters is very distorted and probably needs replacing too, if it's not the crossover.

Probably it is the tweeter. But, check the crossover nonetheless. If the crossover happens to have an electrolytic capacitor in the tweeter filter, sometimes those go bad.

If the capactor(s) in the tweeter filter are metalized film, it is highly unlikely one of those went bad. They tend to be self-healing, and I have never seen one go bad in a crossover, even when there was enough power applied to blow the tweeter.

 

[Old_School_Brad]

If the tweeter is also damaged, I suspect the speakers have been subjected to abuse, and the deformations in the bass driver cones are likely caused by over-excursion.

I would also carefully inspect every component in the crossover, as something may have overheated there.

The voice coils in the seemingly functional drivers may have been excessively hot. While they might still measure as good, the lacquer and wire insulation could have partially melted, making them more prone to failure in the future if left unaddressed.