Carpet underlay, felt or foam?

[LemonTree]

Just wondering if one product is better than another. My attic studio is near completion and should be ready to carpet by the weekend. I was just wondering if carpet underlay was a factor.

I seen some felt underlay on ebay claiming it was 10 times more efficient than foam underlay in the sound and heat transmission department. Sound transmissions aren't a problem for me but if this stuff will cut them down a bit for the same price then why not I'm asking. Here are some stats from the ebay page..

TOG RATING 4.5 APPROX, IMPACT SOUND ABSORBTION 52 DECIBELS, THICKNESS 14 MM

Now, there is no chart or anything and I'm thinking 52db...at what frequency? I'll email and ask. Is there other products like this on the market sold solely as acoustic treatment with frequency absorbtion charts anywhere?

It's only £25 for 15m2..can't go wrong really. Just wondered if anyone had an opinion, thanks

Alex

[Supercreep]

Because of structural transmission and flanking I doubt you'll acheive much in the way of isolation.

But having a nice comfy surface to walk on is nice.

[LemonTree]

Thanks super, we get away with flanking noise by using V-drums...space was a factor too. Before putting carpet and underlay down there is a mild thud downstairs from the kick beater and it's masked by TV volume at conversation level. We have 8" joists up there with 6" of rigid 60kg/m2 rockwool in between, rubber pucks, 2"x2" joists in opposite direction on top and 18mm tonge & groove particle board flooring over the top..all building inspector approved incase you caught the thread I posted a while back with my intentions where a lot of people said the ceiling would fall in and I'd be killed

Did you know you LPC link to wiki gave up this... http://en.wikipedia.org/wiki/Little_People_of_Canada

[tmix]

My only thoughts about it are the felt may be more dense and hense would block sound better than the foam, which won't block anything.
The foam may decouple better, but I doubt it.

I'd probably go with the felt for pad for the density and if you truly need to decouple the kick pad from the floor, build a small platform that rides on something (Compressed fiberglass?) that actually does a decent job of decoupling.

[VSpaceBoy]

I would go for the pad. I doubt either would carry much value for sound absorption. Impact absorption would be like walking on it with hard shoes or dropping stuff on it. Not sound waves through the air.


I would definately use pad instead of felt. The padding will make it feel nice to walk on instead of feeling like youre walking on plywood. It will also help your carpet last longer. With the felt, your carpet will crush down from walking on it in no time at all.