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cookl09
02-05-2013, 04:46 PM
My ported L110 has thin fiberglass insulation lining the inside of cabinet. Was this designed to absorb sound waves? I read that fiberglass insulation does not absorb sound waves (only open-cell foam, mineral wool will do that). Can I replace the fiberglass insulation with another material to do whatever the original design was intended to do (and possibly improve bass response)?

The bass (when standing close to speakers and at distance) can be a little out of control (overpower the other drivers) and boomy (poorly defined) on some CDs and has to be tamed. Are there options to improve this? Stuff the port and add some fill? (I don't want to do that because that will raise the lowest frequency but I will if it will give me a smoother response and better sound.) I do love these speakers very, very much.

grumpy
02-05-2013, 09:23 PM
Tried them on stands? ...18-24" off the floor

cookl09
02-06-2013, 08:46 AM
My main concern is to just replace the fill with the proper material first. Then take it from there. The fiberglass insulation does not absorb sound. I don't know what the designer's original intention was when designing the port, enclosure, fill, etc. I'd like to find out.

Earl K
02-06-2013, 09:01 AM
Your statements about the acoustic properties of fiberglass batting are way, way off the mark .

I suggest that you spend a day ( or so ) reading threads about acoustic control ( as practised ) over at GS's ; Studio-Building-Acoustics . (http://www.gearslutz.com/board/studio-building-acoustics/)

There , you can educate yourself about the various sound absorption efficacies for the materials that you've just mentioned .

:)

just4kinks
02-06-2013, 09:25 AM
Yes, also Vance Dickason's "Loudspeaker Design Cookbook" covers the subject in detail. Summary: leave the fiberglass alone.

DavidF
02-06-2013, 09:17 PM
My ported L110 has thin fiberglass insulation lining the inside of cabinet. Was this designed to absorb sound waves? I read that fiberglass insulation does not absorb sound waves (only open-cell foam, mineral wool will do that). Can I replace the fiberglass insulation with another material to do whatever the original design was intended to do (and possibly improve bass response)?

The bass (when standing close to speakers and at distance) can be a little out of control (overpower the other drivers) and boomy (poorly defined) on some CDs and has to be tamed. Are there options to improve this? Stuff the port and add some fill? (I don't want to do that because that will raise the lowest frequency but I will if it will give me a smoother response and better sound.) I do love these speakers very, very much.

The fill is included to convert some of the sound energy to heat and mitigate the tendancy for sound to keep bouncing around in the enclosure. It is not used to tune the Q of the cabinet which you mention in adding fill or stuffing the port. Fiberglass is actually the better material for the application. Open foam cell is not as efficient in the process. Wool can be used but it needs to be loose fiber and that brings up the question on how to keep it in place (no need to fill the entire enclosure, counterproductive).

Are the L110s new to you? What are, or were, you comparing them to?

Where are they in terms of placement? Near walls, on the floor, etc.