foam for speaker holes.

[bubble_boy]

hey guys, might sound like a stupid question, but i got the little round foam cutouts with my speakers which you can put in those airholes. What does it do? something about bass changing. I tried to see if they have any info on it, but i only see pictures and i don't understand what they are showing.

thank you!

[Shonver]

Hehe.

It's the first time I hear of a manufacturer doing this. Kind of 50's/60's/70's throwback!! Back then, you were amost expected to tune (or even service!) your own system. (Mind you, I once auditioned a passive subwoofer that 3 different length ports for the user to select to his needs.)

I would guess it is to allow you to tune the bass by reducing (attenuating) the port's (a.k.a airholes) contribution, in order to achieve smoother integration with a subwoofer.

What make/model is it?

[chipwelder]

They do two things, lessen the noise from bassport (airholes) (the speaker gets bass output from the driver round thingy that moves, and the port) They will have a greater impact on the higher frequencies that exit the port, because you need denser and thicker plugs to stop lower frequencies, so depending on a lot of factors, they will probably have a larger impact on the midbass. Lower part of vocals and instuments, but not the lowest part. Bass is a pain to stop / absorb...

They will also change the tuning of the speaker box to a (I suspect) smaller extent, depending on the density of the plug, and the tuning of the box, so the type of Bass may change not only because port is now giving less output... but because the speaker system Q has changed. Q is a value calculated from a lot of variables and there are different Q's for different parts of a speaker system...

So in short they make the sound less boomy if the speakers are placed up against a wall, but they affect other aspects of the speakers as well, I would suggest only putting speakers close to the wall and using the foam if you can't place the speakers properly...

[bubble_boy]

thanks shonver.

it is the kef IQ7 floorstanders, but i got it with the centre IQ6c as well. how will these foam inserts affect the base? i have put them in to hear if i can hear a difference, but it just sounds the same to me.

thanks chipwelder, but in laymans terms what will the result in my sound be?

[Viagara]

It's the first time I hear of a manufacturer doing this. Kind of 50's/60's/70's throwback!!

B&W and Tannoy are some of the manufacturers that still supply the foam bungs with their speakers

[chipwelder]

Make the midbass less, possibly bass too.
Make it sound terrribly boxy if the speakers are placed well.
Make the sound less boomy if the speakers are against the wall or placed poorly.

[bubble_boy]

thank you chipwelder, now i understand.

[chipwelder]

  Coolness!