KEF Q 300 CRACK IN DRIVERS

[A K Bhattacharjee]

Hi, My KEF Q 300 has developed cracks in the rubber/foam sheet attached to the diaphragms of the drivers. I am using them for the last eight years. I do not use to listen in high volume, therefore reason behind the cracks is unknown. Any of the forum members who has come across such situation pl share their experience. Forum members are also requested to share their views on the probable effect of this cracks in near future & what is the remedy? I am attaching two images of the drivers. Many many thanks in advance.

 

[efernand1]

Hi, My KEF Q 300 has developed cracks in the rubber/foam sheet attached to the diaphragms of the drivers. I am using them for the last eight years. I do not use to listen in high volume, therefore reason behind the cracks is unknown. Any of the forum members who has come across such situation pl share their experience. Forum members are also requested to share their views on the probable effect of this cracks in near future & what is the remedy? I am attaching two images of the drivers. Many many thanks in advance.

Hi

It all depends on how much the speakers are used and also the weather / room conditions the speakers are placed in. It is said Kevlar cones last longer including the rubber surround. For Example, I am still using Bose 301s Series III which are more than 24 years old and till date the speakers are running fine ...no issues with the cones or their surrounds...

The best thing to do is to get them replaced at the earliest...although there are many videos on youtube to repair rubber surrounds or replace, see what works best.

Dust (with moisture or dry) is the main culprit to wear and tear speaker cones / surround rings as time passes by. Suggest you refer to the guidance available to clean these speakers carefully as and when required to avoid such a situation again.

 

[Passive_audio_enthusiast]

Hi

It all depends on how much the speakers are used and also the weather / room conditions the speakers are placed in. It is said Kevlar cones last longer including the rubber surround. For Example, I am still using Bose 301s Series III which are more than 24 years old and till date the speakers are running fine ...no issues with the cones or their surrounds...

The best thing to do is to get them replaced at the earliest...although there are many videos on youtube to repair rubber surrounds or replace, see what works best.

Dust (with moisture or dry) is the main culprit to wear and tear speaker cones / surround rings as time passes by. Suggest you refer to the guidance available to clean these speakers carefully as and when required to avoid such a situation again.

Depends on where you use it. Certain surrounds crack over time. Depending on the material used the reason can be mostly moisture in your area. Only solution is replacing the surrounds. Get kefs support on this. Do not replace the surrounds with a a generic surround, as the kefs rubbed ones are made that way for a reason. If both speakers don’t have it, you might have to suspect that someone accidentally damaged your speaker by pushing the cone really hard.

 

[MaSh]

Talk to profx Bangalore service center. See if you can just replace the rubber or the entire driver needs to be changed.

MaSh

 

[A K Bhattacharjee]

Hi

It all depends on how much the speakers are used and also the weather / room conditions the speakers are placed in. It is said Kevlar cones last longer including the rubber surround. For Example, I am still using Bose 301s Series III which are more than 24 years old and till date the speakers are running fine ...no issues with the cones or their surrounds...

The best thing to do is to get them replaced at the earliest...although there are many videos on youtube to repair rubber surrounds or replace, see what works best.

Dust (with moisture or dry) is the main culprit to wear and tear speaker cones / surround rings as time passes by. Suggest you refer to the guidance available to clean these speakers carefully as and when required to avoid such a situation again.

Thanks for your reply. PROFX is quoting a very high rate, Rs. 16800 each driver. They are saying that the driver is not repairable so it has to be replaced. Replacing both the drivers is equal to purchasing Polk audio RTIA3. What do you suggest? Shall I go for replacement or think for alternatives.

 

[efernand1]

Thanks for your reply. PROFX is quoting a very high rate, Rs. 16800 each driver. They are saying that the driver is not repairable so it has to be replaced. Replacing both the drivers is equal to purchasing Polk audio RTIA3. What do you suggest? Shall I go for replacement or think for alternatives.

For now use as is...minimum ..see if other alternatives are available which would suit your requirement. Check if the drivers can be sourced through other means...I am sure Profx are not the only ones......they inturn would be sourcing it from some vendor...

 

[MaSh]

Thanks for your reply. PROFX is quoting a very high rate, Rs. 16800 each driver. They are saying that the driver is not repairable so it has to be replaced. Replacing both the drivers is equal to purchasing Polk audio RTIA3. What do you suggest? Shall I go for replacement or think for alternatives.

Oh is that from Pro FX Bangalore? Thats quite an expensive driver. However, move to RTi A3 would be a big downgrade from the Kef. Compare the price difference to speakers at its level or higher.

Do you feel any distortion due to this? Are the cracks deep?

MaSh

 

[Prodigy]

I found this website and looks like they ship the drivers world wide. Reach out to them and see how much it costs and what’s the difference in price between them and Pro FX. I am thinking even with customs paid they should not cost as much as Profx.

KEF Replacement Parts

KEF Replacement Parts & KEF repairing | Speaker Exchange authorized KEF service centre & repair speakers with original manufacturer’s parts

reconingspeakers.com

 

[Passive_audio_enthusiast]

Oh is that from Pro FX Bangalore? Thats quite an expensive driver. However, move to RTi A3 would be a big downgrade from the Kef. Compare the price difference to speakers at its level or higher.

Do you feel any distortion due to this? Are the cracks deep?

MaSh

It must have distortion now as air can easily get out through the gap and also the vibration pattern of the woofer will theoretically be different from what is expected. But one solution could be to use a rubber based glue to fill the gaps as thin films so the effect of a foreign substance is minimal. Logically it’s not worth the quoted repair price. The q300 has almost nothing other than that coaxial driver . I would use this glue method and use it to the core.

 

[A K Bhattacharjee]

Oh is that from Pro FX Bangalore? Thats quite an expensive driver. However, move to RTi A3 would be a big downgrade from the Kef. Compare the price difference to speakers at its level or higher.

Do you feel any distortion due to this? Are the cracks deep?

MaSh

Yes, yesterday I tried to get the sound from either of the speakers. Sound from the damaged one was distorted & that too with low output. I too have thought of applying rubber glue. I have asked Profx to quote price without Twitter. Let me see. Thanks.

 

[venkatcr]

You don't necessarily have to use the 'original' drivers. You should check with a local repairman or a good AV shop as to what to do.

In my case, for example, in my 15 year old Wharfedale 9.5s, two mid range drivers just got torn on both speakers. I took it to the local Wharfedale dealer. He checked with the national distributor, procured specified drivers, and fitted them for me. Now the Wharfedale sing as well as before or even better.

Fitting the 'original' parts is a mind set that all of us have. There could be even better drivers available in the market at half the price.

 

[raghupb]

@venkatcr
This method won't work OP's speaker drivers. They are Uni-Q

Cheers,
Raghu

 

[venkatcr]

My bad. Then there are few options left.

 

[Anshul_J]

Can you not change just the rubber surrounds on kefs?

 

[robin3989]

You don't necessarily have to use the 'original' drivers. You should check with a local repairman or a good AV shop as to what to do.

In my case, for example, in my 15 year old Wharfedale 9.5s, two mid range drivers just got torn on both speakers. I took it to the local Wharfedale dealer. He checked with the national distributor, procured specified drivers, and fitted them for me. Now the Wharfedale sing as well as before or even better.

Fitting the 'original' parts is a mind set that all of us have. There could be even better drivers available in the market at half the price.

Are those replacement drivers the same as the original drivers? If the drivers were different, didn't the crossover or cabinet need changes?

 

[A K Bhattacharjee]

PROFX says that the replacement driver will be the same & original but they will despatch it once they receive the existing one & amount. They have agreed for a discount of Rs.4000 for exchange.

 

[venkatcr]

Are those replacement drivers the same as the original drivers? If the drivers were different, didn't the crossover or cabinet need changes?

They were exactly the same in terms of size, specs and fitment. The technician just removed the old drivers and fitted the new ones in their place.

Maybe one day, when I am not feeling lazy, I will see if I can get 'original' replacement. For now, I am happy with the sound.

 

[Sean de Silva]

PROFX says that the replacement driver will be the same & original but they will despatch it once they receive the existing one & amount. They have agreed for a discount of Rs.4000 for exchange.

Even with that discount it's quite a bit! I'd say time to move on and get yourself a new speaker. Just my two cents.

 

[A K Bhattacharjee]

Can you not change just the rubber surrounds on kefs?

KEF rubber surrounds are not available locally & PROFX does not replace only the rubber. I do not know whether other rubber surround will work on it. I can glue it & fill the cracks. I have not yet decided on replacement.

 

[Anshul_J]

KEF rubber surrounds are not available locally & PROFX does not replace only the rubber. I do not know whether other rubber surround will work on it. I can glue it & fill the cracks. I have not yet decided on replacement.

I asked because I recently got my JBLs repaired, was quoted between 4-6k for 8 inch rubber surrounds, so I find it hard to believe that the whole driver needs to be replaced just because the surrounds have gone bad. I realize that the kef surrounds are a bit different, maybe original KEF surrounds can be sourced from abroad. I am using the kef q150, hence the concern apart from curiosity.