GR20s too big ?

[vatulele]

This is my first ever thread posting so pl excuse any shortcomings !
Ive just moved to a 400year old timber framed building which means i have a listening room that is 17'x14' with a low ( 7' ) ceiling, solid floor with brick wall behind speakers but the rest timber framed with lathe and plaster. The reason for such detailed room info is that my Monitor Audio GR20s which used to sound superb in my old house ( stone walls and 28'x17' ) suddenly sound dreadful with booming loose bass and a feeling that the whole house is shaking with its substantial low bass. I have tried blocking the ports and moving the speaker around with minimal success. Can anyone help with other things I can try, advice on potential damage to the buildings structure and if it ends up with me buying some smaller speakers, any suggestions ?

[ThomasW]

It's not the speakers it's the geometry of the room. The only solution to this is bass traps. These links will get you started

http://home.comcast.net/~thomasw-2/SubwooferSetupandEQpage2.html

http://home.comcast.net/~thomasw-2/SubwooferSetupandEQpage9.html

[vatulele]

ok thanks, how about the shaking house feel, anyone ever heard of a house being damaged by loud music ?

[gianni]

ok thanks, how about the shaking house feel, anyone ever heard of a house being damaged by loud music ?

Yes, but only houses which are more than 375 years old. :W

Your hearing damage will be an issue long before you need to worry about the structure.

[warnerwh]

With that much hard surface area I'd not only add bass traps but some room treatment. In case you aren't aware room acoustics are as important as speakers. It can have a HUGE effect on the sound. Fortunately it's relatively inexpensive and has a great return on the investment. They can be made or purchased depending on your handiness.

If you're not familiar with room acoustics you should go to realtraps.com and read plus watch the videos. Soundwaves are launched in various lengths depending on the frequency. Depending on the dimensions of your room you'll have various peaks and nulls varying alot. Peaks of 8db and nulls of 25 db are common. This is what happened to your bass response. They can cancel each other as well as exaggerate frequencies also.

Imagine letting a little kid adjust a graphic equalizer for you, that's what the room does to sound in all rooms with walls!

[ThomasW]

anyone ever heard of a house being damaged by loud music ?

Timber framed houses are incredibly strong. Since it's been standing for ~400 yrs, I don't think you need to worry about anything, as long as the local termites don't take a shine to high quality music ......

The room is close to being a square. And square rooms are really problematic for bass.

Enter the dimensions of the room in this calculator. It will give you some idea of what you're dealing with.

http://www.mcsquared.com/modecalc.htm

Next you probably want to invest in some test gear to "map" the room modes.

[vatulele]

Thanks guys, sounds like ive got a lot of reading and experimentation to do plus a bit of carpentry ! Will keep you in touch with developments and results. I,m looking forward to the challenge and it will make a nice change from reviewing hifi gear.

[David Meek]

Ive just moved to a 400year old timber framed building

That's awesome in and of itself! :T Can you post some pictures?

One thing you may want to consider is a computer program called C.A.R.A. You "build" your room in the application, "build" or select your speakers, throw in the furniture/acoustic treatments, select the level of detail you want and hit the Run key. It models the acoustics of your room for you. You can re-arrange things over and over 'til you get something that looks good. It's inexpensive and powerful.

[vatulele]

that sounds like a very high tech way to tune a room. I will try the trial and error method with some bass traps and panels first, I like the interactiveness of that. If I cant get a sound I liek that way then C.A.R.A will be my next route. I am having fun trying to find the curved style insulation that i need to make DIY bass traps, there are not many suppliers here in the UK.

Re the house, u seemed quite surprised by the 400 years, thats nothing, my previous house was a converted chapel with stonework and flooring nearly 1000 years old. Those 3 foot thick stone walls and brick floor were great accoustically !

[David Meek]

Hehe, that's one of the true differences between the US and the "Old Countries". When I was in Rome several years back, I was having a conversation with a couple about their recently renovated home. It turns out that their place was several hundred years old and the renovatation was over a hundred!

Here in the 'States we have a real hard time coming up with a building - other than archeological relics - much over 200.

[vatulele]

It looks like its going to be difficult to get hold of large bore pipe insulation here in the UK, so I may have to go down a DIY route. Is there any reason why I cant just use normal loft type fibreglass insulation if i can find a way of compressing and stiffening it around a tube of the bore I need ? A comparison of densities should give me an idea of the thickness of loft insulation I need to start with if I,m looking a final thickness of 1 inch. I am thinking I should be able to soak the loft insulation in some sort of sizing solution then compress it around a tube and allow to dry. Sounds simple but I bet it turns out to be a right mess !