Window Rattle

[BigDan79]

I have 2 windows in my theater room that rattle pretty good when the bass kicks in. Any reasonable ideas on what I can do to reduce or stop the rattle?

 

[ddude003]

Do a frequency sweep with REW and discover the frequency that makes the windows rattle... Use that miniDSP to cut that frequency down...

 

[BigDan79]

They rattle at the lower frequencies. The problem is I want to feel the bass so I don’t want to cut the output. I was wondering if I got a foam diffuser the size of that window would it absorb the waves enough to reduce or stop the rattle.

 

[ddude003]

I doubt a "simple" foam _diffuser_ would _absorb_ unknown low frequencies... I would still suggest you use REW to discover what specific frequencie(s) range is needed to deal with the rattle... Once you know the specific frequencies, you can test by cutting those specifically with a filter using your miniDSP or buying/making a low frequency _absorber_ targeted for your specific window issue... You may be surprised that the cut needed could be so narrow you won't be able to hear a difference in your output...

By the way, do you currently have any acoustic room treatments?

 

[BigDan79]

I currently have 4 wall panels now

 

[Travis Ballstadt]

Depends on what type of Windows and where the rattle is coming from. Weather stripping, caulk, etc could help, if the pane is rattling against the frame. Tighten the seal and give everything less room to move.

 

[ddude003]

I assumed that @BigDan79 would have done the basics with standard window maintenance... Not knowing what the resonant frequency issue we are dealing with is, we could guess all day about how to deal with the issue...

After running across a photo of @BigDan79's HT room, in another thread, leads me to believe there is not enough base absorbers in the room... Nore enough broadband absorption for that matter... And that is pure guesswork...

Given so little information to go on, my best guess for the window issue would be some Mass Loaded Vinyl to hang over the window opening or even attach directly to the window glass...

It would still be nice to know the resonant frequencies we are dealing with so @BigDan79 does not waste his $$$ on pure conjecture and guesswork...

 

[lemoncadillac]

Hi
Window glazing. the Glass rattle because it is loose. Pickup some glaze at your local home store. Pack it all around the glass. Use a good putty knife.
Lemon

 

[BenToronto]

Just adding to the comments in posts 6 and 8, the point is that some part of the window assembly (visible or hidden away, the whole frame or just a pane, etc) is vibrating sympathetically with some frequency. Endless simple cheap fixes, once you know what part. So Step One is to learn the freq using a sweep first, so you can play it for testing.

Sometimes just a piece of origami stuck between the window and the frame will stop it cold.

But generally, it means you should be proud of how low your system goes.

BTW, it will do really horrible things to an FR in REW.

 

[BigDan79]

Thanks for all of the replies. My house is 3 years old so the windows are pretty new. I can see the windows moving in and out when there is heavy bass.
What do bass traps do? Reduce bass or vibration?
What would you recommend stuffing in the window?

i plan on running bass sweeps one of these weekends.

 

[BenToronto]

Bass traps are absorbers that are so broad-band that they even absorb bass. Some fancy ones are a bit tuned or are located to aim for the bass. Your room may possibly sound better but in general, a whacky idea to "fix" your room or EQ your sub when the problem is just the window which is resonating.

There are a million things that might be used to reduce movement by rigid fix or by adequately damping it. No movement, no rattle. Betcha' you can just fold-over a sheet of paper ("origami") and jam into the window jam gap.

 

[BigDan79]

Any recommendations on good reasonably priced bass traps?

 

[ddude003]

Pfft... No more "whacky" than "origami" or heck why not just try a spit-wad... And by the way, I did not say to kill all the base or sub base... What I said was to find out what the resonant frequency was and cut it... Just it... And his miniDSP is made for doing that... And yes, if the three year old window is having issues with its weathering then fix it with new grommets or rubber what-evers...

And my guess still stands that it is a resonant frequency issue with the window pane itself... We will never know until @BigDan79 takes the effort to see what's going on with REW...

Have a look at the GIK Soffit Bass Trap with the Range Limiter...

 

[BenToronto]

The resonant freq of the window is narrow but the narrowest tuning of a DSP will knock a major portion of the bass off kilter, as anyone who has tried spot-EQ in the bass can tell you. Like swatting a fly with a sledge hammer.

And anyone who has worked with gaskets and loose windows will also think folding paper until it is just the right thickness and just the right location for the gap in the jamb is plenty smart way to tame the window vibration.

But I should add another of the multitude of tools we audiophiles can use here: winter liquid weatherstripping in a caulking tube. It is like a bead of rubber cement (not RTV silicone but old-time rubber cement and pretty cheap too) made not to disfigure paint and can be easily pulled off when you want in one long strip. It would work like a charm. Great stuff for making irregular bases on speakers, lamp, etc mate intimately with flat surfaces.

 

[BigDan79]

Ok. These sound like easy enough things to try. I don’t think I can stop the windows from moving but I think there are ways to dampen that movement. Thanks for the advice! I also am shopping for bass traps. I am curious how they would affect the sound.

 

[BenToronto]

Bass traps are broad band - again the sledge hammer approach and expensive, at least apropos window resonance. It may help the over all sound in your bass but posted experience seems to be mostly unfavourable.. Which is what a review of the physics would lead you to expect unless you do some maximum redecorating. Active traps (kind of resembling motional feedback backwards) is really interesting concept.

In any case, great waste of time and money unless you understand your problem first. All it takes is a sweep sound and a thumb on the culprit.

 

[damic]

My large (130cm x 120cm) window used to rattle at about 40Hz, due to thin glass, I suppose 3mm. The widow is with double glass, not vacuumed. Simply, I stacked in the center soft rubber door stopper, so both glass are under light tension and solved the problem. I suppose, the vibration moved at 80Hz that are not audible.

 

[BenToronto]

Good news. Clever use of a rubber wedge.

While there must be some gap so windows can open, not right to have a pane loose enough to rattle. Check out the removable draft caulk ("draft" is the key google search term, not silicone unless you have a case of terminal audiophilia).

 

[BigDan79]

So I did a quick bass sweep. The rattle comes and goes from 15-35hz. I ordered some foam to stuff in the jams and the Dap seal and peal. I will look from some rubber wedges too. Hopefully one or all will help.

 

[BigDan79]

I was messing around with the window after getting some window air conditioner foam. I found that there is a metal piece that travels up and down with the window in the frame channel. I stuffed the foam to cushion the metal from contacting the frame when vibrating in and out. This has greatly reduced the rattle. I am going to shop around for some thinner foam with an adhesive back to cushion the metal piece from the window left to right movement. I think the ac foam is doing good isolating the frame contact.

 

[BigDan79]

Most of the vibration has been reduced except at the very low frequencies. I have stuffed the seams, shimmed the window and also added additional screws. I think my next step will be adding additional room acoustic treatment. More wall panels, maybe some bass traps, curtains etc. The sound is a little on the bright side so I don’t think adding treatment will make it dead sounding. I would like to warm the sound up a bit and reduce the rattle at the same time.

 

[BigDan79]

BigDan79 room treatment is a great idea. I see our systems are similar, you are going 9.3.6 and I am going 9.2.6, The results I got were better than buying a new processor and a lot less $$$. If you check youtube there are a series of videos from audioholics where they interview Anthony Grimani. I followed his "recipe" to the letter and it worked out great. For absorprtion I used inexpensive treatments from Troy Studios I bought on Amazon. For diffusion I used a variety of treatments from Auralex. If I were to do it again I would have simply purchased a room kit from Anthony's company and have skipped the trial and error. Let me know if you want me to post some pics.

Wow. Thanks for the info. Please post pics and provide links for the items you are talking about.