Rock Wool or OC 703, which is preferred?

[NuSkoolTone]

Hey, I'm about to venture into acoustic treatment for my small room (Like 9x9).

I am comparing to companies products and the Prices are comparable. One uses Rock Wool in their products while the other uses OC 703. Both their lab results appear to show effectiveness. Is one preferred over the other? Do they perform any different sonically? Can either be just as good compensated by the design?

Thanks.

[planet red]

If you can find them for about the same price I'd say get 703 because its easier to work with.

I found rockwool here in town thats 8lbs per cubic foot thats super cheap and very effective, but not fun to cut or place in traps. So far I've used 42 pieces of it and have another 42 to go this week. The difference in sound quality is indescribable.

[cramseur]

check the absorption coefficients here:

http://www.bobgolds.com/AbsorptionCoefficients.htm

If they're similar then either use the cheapest or the easiest to work with. I used multiple layers of a lower density rockwool, because I got it for free!.

[Glenn Kuras]

Welcome to the world of acoustics.
We where just talking about this here http://messageboard.tapeop.com/viewt...17c958c20e3ea6
It is a lot to read but pretty good info for yourself.

Glenn

[NuSkoolTone]

Originally Posted by myfipie

Welcome to the world of acoustics.
We where just talking about this here http://messageboard.tapeop.com/viewt...17c958c20e3ea6
It is a lot to read but pretty good info for yourself.

Glenn

Hey thanks. The only thing that concerns me in that thread is that Rock Wool could "get lumpy and sag over time". To what extent are we talking here? Would it start to deform the trap, or lose performance?

[Ethan Winer]

Originally Posted by NuSkoolTone

Hey thanks. The only thing that concerns me in that thread is that Rock Wool could "get lumpy and sag over time". To what extent are we talking here? Would it start to deform the trap, or lose performance?

I don't think the performance will degrade unless the material is so poorly supported that it actually falls apart.

--Ethan

[6strings]

Originally Posted by NuSkoolTone

I am comparing to companies products and the Prices are comparable. One uses Rock Wool in their products while the other uses OC 703. Both their lab results appear to show effectiveness. Is one preferred over the other? Do they perform any different sonically?

As said above, Rock wool/mineral fiber can be found in 8pcf while 703 is 3pcf.

This means rock wool can theoretically be a better product for trapping low end (it's denser), but is MUCH heavier. I used mineral fiber panels for corner bass traps but went with lighter 703 for an acoustical cloud and velcro-mounting 2" panels on floating walls I didn't want to put holes in.

[mdsmith64]

I used the 8lb rockwool myself. It was a bit looser than I would have liked, but still manageable. I haven't noticed any sagging yet. Thinking off the cuff here, I suppose one could fashion some sort of cloth strap system to support the middle section to prevent sagging (I actually used cloth straps on the tops and sides of my frames for support - http://pariah-now.com/images/Bass%20Trap%202.jpg and http://pariah-now.com/images/Bass%20Trap%201.jpg ). Maybe not so pretty, but it would work (by the way, I tightened up the fabric and pinned it back to make a more profession look before I hung the traps. The above pictures don't do them justice). The traps I made out of 8lb rockwool have made a stunning difference in my room. I had to completely readjust my ears to the room and at first I didn't like the sound. Now that I'm readjusted I'm a happy camper. It's funny, you notice the difference just from the way your footsteps sound as you cross the threshold into the room. Of course the bass freqs are tight, tight, tight and my monitors now have a more distinct sweetspot. They sound like nearfields now.

Best Regards,

Mike.

[scrubs]

Dunno what brand of mineral wool you're using, but I've found the 8pcf mineral board (Delta/Rock Wool) to be very sturdy. I can't imagine that it would sag. Yeah, it's a little messy to cut, but a drywall saw makes pretty quick work of it.

FWIW, I think the original poster was looking to buy pre-made panels, so all that stuff about "easier to work with" is moot. The acoustic properties are similar at similar densities and not different enough to fret over (703 is 3pcf, 705 is 6pcf, I think). The higher density mineral wool is quite heavy for clouds, though.

[NuSkoolTone]

Originally Posted by scrubs

FWIW, I think the original poster was looking to buy pre-made panels, so all that stuff about "easier to work with" is moot.

That is correct. I am not going the DIY route. The offerings I'm looking at seem reasonably priced. Frankly I just don't have the time for another project on my plate, unless it's an hour or two project.

[dtucker]

I used Rock Wool when I made my traps about three years ago. I've moved since then and only have a few up right now. On one I have noticed some sagging, but the others seem to be just fine. And they work REAL well, too. When I first installed them in the first studio they really did wonders for my low end. I would recommend them.

But, truthfully, either that or the rigid fiberglass would do just fine.

[mdsmith64]

Just for fun, here are some pics of my Roxul rockwool bass traps installed in my box...er, project studio (10x12x8):


http://www.pariah-now.com/studio_traps.htm

Best Regards,

Mike.

[Earwitness]

I used both... mostly pannels with 703 but lower toward where the drum kick is some rock wool in a few smaller 4' X 4' pannels.

you can see mine at
www.myspace.com/earwitness