I'm using my Klipsch Quartet (the heritage 8" woofer "Forte" design with a passive radiator on the back) in a very compromised location. Recently moved into a small one room (studio style) guest house to help family and have to put speakers and stereo into an 8 foot wide closet area. No other wall space is available. The speakers front baffles are pulled out in front of the opening, and there are no doors or coverings on the front.
I know it will never sound good, and I do plan on demolishing the closet, but I want to keep using these speakers. For the time being I'm looking for a way to eliminate the passive radiator on the back. I could construct small boxes around the passives with dampening material, but I thought I would ask the group if there are better strategies. The closet material is textured plaster, and I could line the interior of the closet with dampening material. Any thoughts?
I know it will never sound good, and I do plan on demolishing the closet, but I want to keep using these speakers. For the time being I'm looking for a way to eliminate the passive radiator on the back. I could construct small boxes around the passives with dampening material, but I thought I would ask the group if there are better strategies. The closet material is textured plaster, and I could line the interior of the closet with dampening material. Any thoughts?
Are you trying to minimize bass because they're close to the rear wall or is there something else going on that prompted the desire to eliminate the passive radiator?
And are you intending to absorb bass frequencies with your damping material or are you just trying to stop rattles?
Instead of building a box over the radiator, it would probably make more sense to replace the passive radiator with a disk of MDF. You can mount it using the same holes that the passive radiator used. Find some nice cardboard boxes the passive radiators can go in, and store them somewhere for future reversal of the process. Maybe they'll fit in the closet behind the speakers 🙂
And are you intending to absorb bass frequencies with your damping material or are you just trying to stop rattles?
Instead of building a box over the radiator, it would probably make more sense to replace the passive radiator with a disk of MDF. You can mount it using the same holes that the passive radiator used. Find some nice cardboard boxes the passive radiators can go in, and store them somewhere for future reversal of the process. Maybe they'll fit in the closet behind the speakers 🙂
Because the space is semi-enclosed, the rear facing passive is muddying the bass with reflections. The speakers are about 18" from the rear wall, so it's the side walls for the closet that are the biggest problem.
I considered replacing the passive, but I was worried that would effect the proper functioning of the woofer. Anyone think it would be a bad idea to try?
I considered replacing the passive, but I was worried that would effect the proper functioning of the woofer. Anyone think it would be a bad idea to try?
Absorbing bass is a little difficult to do with typical foam, if that's what you're intending. Most sheet foam charts don't go below 125 Hz (and typical 4-inch foam only has an absorption coefficient of around 0.2 at 125 Hz, with decreasing absorption as frequency goes down).
Absorbing/foam bass traps are normally pretty deep and designed to go in corners.
Diaphragmatic/panel/Helmholtz absorbers are another option, but they take some work if you want to roll your own.
Sealing your enclosure won't hurt the woofer directly, but it obviously changes the behavior of the system. Whether that's a happy result for you is up to your tastes and desired listening levels. The sealed box will have more excursion compared to the passive radiator box around the radiator's tuning frequency. But sealed will have less excursion and more stability below that frequency.
Some KEF speakers come with partial and full port plugging foam to achieve basically the same thing. I've read reviews where other manufacturers also tell people to plug ports to tune response in an unruly room. It's a pretty common method.
Assuming you can do it easily, just running a quick test of the passive radiator removal/hole cover on one speaker is probably the quickest way to decide if it's the right answer for you.
Absorbing/foam bass traps are normally pretty deep and designed to go in corners.
Diaphragmatic/panel/Helmholtz absorbers are another option, but they take some work if you want to roll your own.
Sealing your enclosure won't hurt the woofer directly, but it obviously changes the behavior of the system. Whether that's a happy result for you is up to your tastes and desired listening levels. The sealed box will have more excursion compared to the passive radiator box around the radiator's tuning frequency. But sealed will have less excursion and more stability below that frequency.
Some KEF speakers come with partial and full port plugging foam to achieve basically the same thing. I've read reviews where other manufacturers also tell people to plug ports to tune response in an unruly room. It's a pretty common method.
Assuming you can do it easily, just running a quick test of the passive radiator removal/hole cover on one speaker is probably the quickest way to decide if it's the right answer for you.
