help needed: in-walls & low ceiling

[Kosta27]

hi all,
my question concerns adding first reflection point acoustic panels to treat my new home’s pre-existing basement 5.1 theater set up.
Now for the fun part, It’s a 14 x 14.5 x 7.7 ft space with in wall speakers centers located 1.5ft from the ceiling. this tends to cause slap echo effects, although currently due to sitting placement (couch 4ft from back wall) the base is fine. it’s like the i’m treat a upside down room Appreciate any advice thank you again!

 

[ryanosaur]

hi all,
my question concerns adding first reflection point acoustic panels to treat my new home’s pre-existing basement 5.1 theater set up.
Now for the fun part, It’s a 14 x 14.5 x 7.7 ft space with in wall speakers centers located 1.5ft from the ceiling. this tends to cause slap echo effects, although currently due to sitting placement (couch 4ft from back wall) the base is fine. it’s like the i’m treat a upside down room Appreciate any advice thank you again!

It's not the position of the speaker that creates a slap echo: it is the boundaries of the room that do it.

Please describe the finishing and furnishing of your room. Drywall? Ceiling? Carpeting? Furnishings? Appointments like artwork or tapestries?

 

[Kosta27]

It's not the position of the speaker that creates a slap echo: it is the boundaries of the room that do it.

Please describe the finishing and furnishing of your room. Drywall? Ceiling? Carpeting? Furnishings? Appointments like artwork or tapestries?

Thank you for your quick reply! i’ve attached pics of my room. I’m willing to rearrange the furniture but would rather keep the in wall locations (10in sub behind the couch).

 

[TLS Guy]

Thank you for your quick reply! i’ve attached pics of my room. I’m willing to rearrange the furniture but would rather keep the in wall locations (10in sub behind the couch).

Unfortunately that room is close to a worst case scenario. The room is basically square, and that is a terrible start. The next problem is that your speakers are far too close together. You would be far better off without the center speaker.

Room dimension ratios have a disprporionat effect on sound quaility. There is no remedy for that apart from pushing walls out, moving to a different room or moving residence.

What are those in wall speakers? They will be exacerbating the situation most likely causing bass reinforcement. In walls are tricky, but a lot depends on the design of the speaker.

 

[Kosta27]

Unfortunately that room is close to a worst case scenario. The room is basically square, and that is a terrible start. The next problem is that your speakers are far too close together. You would be far better off without the center speaker.

Room dimension ratios have a disprporionat effect on sound quaility. There is no remedy for that apart from pushing walls out, moving to a different room or moving residence.

What are those in wall speakers? They will be exacerbating the situation most likely causing bass reinforcement. In walls are tricky, but a lot depends on the design of the speaker.

Thank you for the reply, as for the speakers: 2 way Boston Acoustic. I’ll look into turning the fwd right channel into the center channel and moving the other speaker to other side of the fire place for a retractable projector setup. Although I would i’m not experiencing boominess, probably since i’m not playing at thx reference levels, usually under 80db. I’m still looking at treatment recommendations for under the vent for the left channel.

 

[TLS Guy]

Thank you for the reply, as for the speakers: 2 way Boston Acoustic. I’ll look into turning the fwd right channel into the center channel and moving the other speaker to other side of the fire place for a retractable projector setup. Although I would i’m not experiencing boominess, probably since i’m not playing at thx reference levels, usually under 80db. I’m still looking at treatment recommendations for under the vent for the left channel.

Here I think we see the cause of your problem. I don't think those speakers are actually in walls. This is a big issue as in wall speakers have to be designed without Baffle Step compensation. The reason is that an in wall speaker has no half space/full space transition. So if you use a speaker designed to be free standing and put it in wall you have a major problem. If they are not in wall designs, then I bet you have a really "chesty" sound.

 

[Kosta27]

You’re wrong, they are indeed in walls, see link below:

Boston Acoustics CS 275

In-wall speaker

www.crutchfield.com

 

[TLS Guy]

You’re wrong, they are indeed in walls, see link below:

Boston Acoustics CS 275

In-wall speaker

www.crutchfield.com

It does not mean they actually designed them as in walls though.

That is the problem, there are a lot of in walls that are not. They just change the cabinet and not the crossover.

Anyhow your best way forward, is to put the speaker furtther apart and make you front a dead end if the aesthetics will tolerate it.

As a last comment, even if you have no BSC in the design, you still get some low frequency gain from the font baffle reinforcement of the wall. In a room of your dimensions that is a problem, unless you are prepared to convert the speakers to an active design with electonic crossovers.