Treatment Ideas for dedicated HT room

[Mattlock]

Now that I've got my sub built with BFD filters set, my curve is "good enough" given the fact that I cannot locate my sub anywhere but in the rear due to size , now I am considering possibly building some traps just to enhance my overall sound quality.

SteveCallas suggested the following:
As for bass traps, in order to affect frequencies below 80hz, the traps would have to be extremely thick. I doubt that is a realistic option. However, adding some absorption to the room in the form of pannels or corner traps should help the overall sound quality, even if it isn't really affecting the low end bass.

Based on my pics, what specifically would be some good starting places for traps. (corner traps is obvious but what about panel locations??)

Btw...I have a large sonosub sitting in rear where the left surround is located in the pic (next to the lamp)...actually moved the surround to the left a little further above door.

all suggestions welcome..

thanks in advance
Matt

[bpape]

Hey Matt.

I don't know the dimensions and seating location of the room so hard to be specific. In general, I would offer the following:

- The front speakers are IN the corners. You MUST treat those corners. I would suggest pulling them out a bit and working with some chunk style absorbers. 17x17x24" is a good size that will perform will down into the 40's. You may have to cut back to 12x12x17 due to screen size.

- The front wall needs to be dead 100% in a multi-channel room. Since the screen is so large for the room width, the only additional place is below the screen. 2" will be a good starting point. This will help with boundary issues.

- Treat the middle of the rear wall of the room the best you can with something at least 4" thick to control cancellations off the rear wall. This is good down into the upper part of the sub range and will help some below that.

- Make sure you address the first reflection points on the side walls for better focus, smoother response (off axis reflections are normally very different from direct sound), and improve the overall decay time of the room. Again, 2" or more is preferable here.

Bryan

[superchad]

Bryan,
Did I read you correct that you would make wall behind speakers 100% dead?

I happen to use Di-Pole mains and find live wall behind speakers and dead wall ib rear of room works great, I have Corner traps all around, first reflection panels and its working pretty well.

Here is an interesting improvement I found by accident, friends and family were over for the weekend and due to lack of room a friend stayed on Queen Size Walmart air mattress, during the day being lazy we just proped it up against wall behind front speakers. Well we had a music get-together and the system sounded fantastic. I think the mattress was both a diffuser as it had large dimples to simulate springs on mattress and a suede sort of finish but it also trapped some bass, try it if you can stand the look and have one around.....but its not practical for movies ofcourse but perhaps can shpw how room items make everything sound better. cheers

[bpape]

Well, in HT mode, dipoles are not a good choice for the mains - sorry. The front wall needs to be dead to keep reflections from the surrounds from messing up the front soundstage and image lock. What you likely heard was some high frequency absorbtion from the suede like covering emulating a very small amount of front wall deadening.

The wall behind the seating can be dead - but should be bass/lower mid only - something like a 703 with FSK face. This gives good bass control, minimizes nulls off the rear wall, yet still allows the surround field to be more lively.

Bryan

[superchad]

I will have to disagree about Di-Pole fronts, having owned several Hi-end sealed cone and dome speakers and comparing them to my current VMPS, my past Magnepan and even my past Electrostats in a properly placed set-up in a good room with proper tuning Di-Poles sound great, maybe even better but certainly not worse............in any event I focus on optimal music and HT is a simple bonus but the odd thing is that if you get the music right, the HT will be great aswell, the reverse cant be said.

[gullfo]

it may be that moving the dipoles out will give them better response and give you room for the corner traps. another option - use the overhead space to build up a set of soffits to match the existing hvac soffit and make that your traps... somewhat less optimal than the vertical corners but will leave the floor space intact.

[bpape]

And if music is the primary goal, that's fine. The lack of treatment on the front wall in that case is a compromise to multi-channel performance that you're willing to make.

Bryan

[superchad]

bpape wrote:

And if music is the primary goal, that's fine. The lack of treatment on the front wall in that case is a compromise to multi-channel performance that you're willing to make.

Bryan

You suggest that my surrounds' sound travels 16ft, past my reflection panels on side walls bounce's off the wall behind my mains and is negatively affecting the sound?
I am very comfortable taking that chance!

[bpape]

Yes. I'm suggesting exactly that. The refection panels on the side walls will catch some but not anything coming from the rear surrounds firing directly at the front wall. Treating the front wall fully is pretty much universally agreed as required for purely HT duties.

As I said, if you're leaning toward 2 channel being more important and having dipole/bipole type speakers, then it's not an option - but it is most definitely a compromise for HT duties.

Bryan

[superchad]

My rears are dipole and dont fire direct frontward, my sides ar 16ft and rears are 24 ft from front wall so this is no comromise that I can see or hear,I do focus on music but ofcourse I want great sounding HT or I would not have invested anywhere near the amount of time and money into my room and rig.
But you do have me inteested in just why this may not be good and exactly what the negatives may be so if you could explain I would like to learn new ideas...............thanks!