5.1 vs 7.1 For My Room - Need Advice

Hi,

I have a family room that is 19.5'x17'. My front speakers are along the 17' wall firing into the long direction. My primary seating will be 3' off of the back wall and I cannot move it any further away. In a 7.1 set-up I would have the side speakers adjacent to the seating and 7' away from each listener (love seat). The rear speakers would be mounted on the rear wall 3.5' to the sides of each listener. All surround speakers would be about 2' above ear level.

Do I have sufficient room behind the couch and sufficient spacing between the side speakers and the rear speakers to make 7.1 work? Or is 5.1 sufficient?

Is there a rule of thumb for the amount of separation between the side and rear speakers?

Another option for the side speakers - let me know if this would work:

I have a very narrow area to mount my side speakers. If I have to I will make it work, but it's not pretty. I have room on my side walls 5.5' in FRONT of my listening position. I can position them straight across the room or angle them back to the listening position. Do you think this is acceptable or will I get some strange surround effects? How would you position them?

Thanks for the help,
Greg

Sanjay,

Attached is a room layout and a photo to better visualize the scenario. Note: the photo does not portray the correct furniture layout.

The side speakers will be either mounted on the sidewalls or placed on high stands, however there is not a lot of room on the left side due to a window nearly abutting a fireplace (not much of a sidewall......none, really). This was why I asked about placing the speakers well ahead of the listening position (between the two windows)..............kind of knew that answer, but had to ask!

For the side speakers I have the following options (the constraints mainly apply to the left side speaker):

1. Place on high stands

2. If a very thin speaker, such as the Golden Ear Super Sat 3 or 50, I can mount it to the window trim next to the fireplace.......wife nixed that idea!

3. Mount it above the window between the trim and the 8' ceiling (9.5" clearance). Again, if using the Golden Ear speakers I can mount it horizontally if I get the center channel version. As these speakers are only 4.75" wide I would have a clearance to the ceiling of 4.75". I would tilt the speakers down towards the listening positioning.

4. Mount the speakers below the window and tilt them up towards the listening position, but I think that would sound weird.

5. Just go with rears only in a 5.1 set-up.

Good advice on the rear speakers being toed in.........I can do this. Would you still do this in a 7.1 set-up.

So, given the above options what are your opinions of each? My thinking is that the near ceiling mount may be the best option. Of course you may suggest that the added performance in a 7.1 set-up with any of these options is not a significant enough difference and just to go with 5.1.

Thanks,
Greg

Cool....thanks for the advice on the speaker positioning and the room layout. I'll try the room layout and see how it flows.


I understand what you are saying. My concern was that with the side speakers angled down I would reduce the ceiling bounce and the bass heaviness due to being close to the ceiling. I'll try it both ways and see how it works.

As you may have surmised, I have been contemplating the Golden Ear speakers for two reasons:

- footprint (especially width for that challenged side speaker placement)
- dispersion (monopoles that didn't have that direct in your face sound)

Thanks for the comments and advice, guys..........appreciate it!

Greg

Agreed! Maybe I'll just put the chair there and feel like captain Kirk! My lowly family and guests can can have the side seats. I think my wife would put phasors on stun............if I'm lucky!


Another good point, but then I can't do my captain Kirk thing!

Yes, the couch does have many advantages. I'll move my furniture around and see how it works. It's one thing to lay it out in Visio and another to actually test it out.



The Golden Ear's are designed for on wall mounting. Home theater Mag just reviewed them and rated the -3 db point for the 50's at 107 Hz and the 3's at 179 Hz. I'm not sure how the speakers were measured: wall mounted or free standing (they do come with a small stand).

How much low frequency extension is typical due to the boundary effect?

The ceiling bounce would probably help with diffusion of the sound.

Thanks again for all of the great comments.........if you see anything please comment,
Greg

Golden Ear was under fire in the speaker forum for the frequency response. I will take your advice and check with the Speaker forum for other potential candidates. What I really liked about the Golden Ear's was the wide dispersion. I don't have room for dipoles or bipoles on that header above the window.........I don't think? I don't want too direct of sound. Although for 7.1 I don't really know what I want: direct or diffuse?

I'll see what else I could find.

Thanks,
Greg

Haven't really thought about them.....would help a lot with placement issues.

Although, I think many people don't like this option because the surround effects sound weird coming from the ceiling........although how would that compare to a speaker mounted just below the ceiling, as I am contemplating......same issues?

Thanks for another option to kick around.

Greg

Thanks for the advice. I haven't given up on box speakers yet, but it's good to know that in-ceiling speakers may work, as I have sufficient room to get them away from the seating.

I have taken your advice and posted in the "Speakers" forum for smallish surround speakers with good bass response and got some advice. One is a discontinued Martin Logan center channel/surround speaker that may fit the bill.

I do have a question regarding the low frequency performance of the speaker and how it relates to the cross-over frequency. I've heard a couple of things:

1. the speaker should be able to play flat one octave below the cross-over frequency (or above, depending on which way your going)

2. The speaker should be down -3 db at the cross-over frequency (I believe this is true if both speakers (sub and speaker) roll-off at -24 db/octave per THX specs)

So, given the Golden Ear example of -3 db at 107 Hz means a cross-over of ~ 200 Hz for number 1. and ~ 100 Hz for number 2.? If true, a lot of surround info can be missing, especially for the number 1. scenario with a 200 Hz cross-over! Given the common 80 Hz cross-over means that the speakers would have to play down to 40 Hz.

Is this true, as I'm sure most surrounds don't get anywhere near that? Am I not understanding something?

Thanks,
Greg

Understood!

Thank you for your all of the help..............it is greatly appreciated.
Greg