# Foam vs. Rubber Surrounds



## Chiliman

Is there any reason why foam surrounds have been basically abandoned in favor of newer rubber/silicone surrounds? I was just told by someone i work with that foam has a more 'true sound' and wanted to know if there was any truth in that as well.

 - Chiliman


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## phergus_25

Quote:


  Originally Posted by *Chiliman* /img/forum/go_quote.gif 
_Is there any reason why foam surrounds have been basically abandoned in favor of newer rubber/silicone surrounds? I was just told by someone i work with that foam has a more 'true sound' and wanted to know if there was any truth in that as well.

 - Chiliman_

 

I think its mostly that foam surrounds can rip and desenegrate over time
 that being said my speakers have foam, and I like it that way


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## Wodgy

Yes, it's because foam rots over time. People who claim there is an audible advantage to foam are just trying to sell substandard product. There's no reason to put up with foam surrounds these days.


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## Chiliman

so, there is no sonic improvement of foam over rubber i take it?


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## Wodgy

Quote:


  Originally Posted by *Chiliman* /img/forum/go_quote.gif 
_so, there is no sonic improvement of foam over rubber i take it?_

 

It's impossible to know for sure, since you're always comparing apples and oranges. You can't swap a foam surround with a rubber surround and listen to the change; even if you did, it would change the TS params. However, all high end drivers (in terms of price) use rubber, so drivers with rubber are likely to have higher performance and thus sound better. Foam points to cost-cutting measures.


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## RedLeader

I like the rubber in my titans... and I like the foam in my 9SE, though on one cone its wearing out. So... I like the rubber better


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## phergus_25

Quote:


  Originally Posted by *Wodgy* /img/forum/go_quote.gif 
_It's impossible to know for sure, since you're always comparing apples and oranges. You can't swap a foam surround with a rubber surround and listen to the change; even if you did, it would change the TS params. However, all high end drivers (in terms of price) use rubber, so drivers with rubber are likely to have higher performance and thus sound better. Foam points to cost-cutting measures._

 

there are $1000 full range drivers with foam, well alot of speakers with foam. So I think that is alittle overboard.


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## Sovkiller

Foam were lighter than butyl and rubber surrounds, and fabric also, though the extended use during the past years, as all you want is to minimize the weight to move the cone faster, but foam has a huge disadvantage as many had stated, it rots over time, and need to be replaced, maybe every 10-15 years (that is a lot of time if you ask me)
	

	
	
		
		

		
		
	


	



 Aslo in downfiring subwoofers you need low mass cones, butyl and rubber usually weight too much, and once you place them upside down...forgetabout it!!!! 

 Note: it was used in really expensive drivers as well, not only in cheap ones, just one that I recall, my Shiva Avatar 12" subwoofer, that at that time beat the dust of many good competitors, with an insane (at that time) excursion, and other parameters, was made by Adire audio, is rocking now its 10 year mark and keep on rocking, foam is literally like new, and the sound is extremelly good and smooth...


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## roadtonowhere08

I have a foam surround on my sub woofer and rubber surrounds on my speakers drivers. It will be interesting to see what lasts longer. I do rub my speaker surrounds with Mink Oil every now and then. Really makes them look like new. 

 Whatever you do, keep speakers away from those Ionic Breezes. The ozone they emit eats away at surrounds.


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## Ligeia

Foam is a little bit more compliant than an NBR surround, but certainly less durable. Just like all materials in a speaker, it is not their individual performance that matters, but the performance of the summed parts. For example, I mentioned foam is a little bit more compliant, but using NBR is of no concern if the spider is compliant enough that you meet the Cms/Kms target for your design.


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## phon-o-phile

I agree.
 It comes down to the speaker designers parameter for what he/she wants out of the speaker and then ultimately the cost.
 Foam or rubber for surrounds?
 Keep it in perspective. Some maufacturers use (doped or treated) paper cones, some use metal or Kevlar. So just saying that one type lasts longer than the others, my give you idea of their half-life but does not make one sound any better than another. 
 If you plan on keeping them until you are 85, look at lifespan. On the other hand, get what sounds best.


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