Is it possible to have rear surrounds too far behind?

Discussion in 'Speakers' started by Nick B, Jan 18, 2004.

  1. Nick B

    Nick B Stunt Coordinator

    Joined:
    Dec 8, 2003
    Messages:
    65
    Likes Received:
    0
    Hello All:

    I will soon be installing my 7.1 set up and have a question for the forum regarding placement of the rear surrounds. I will be hanging "adaptive dipole" surrounds on the side walls and be placing monopoles on the back wall as back surrounds. Here is my question:

    From my front speakers to my rear wall, I find myself with over 21 feet.

    The best seating distance from my 50" RPTV appears to be approx 6 feet. This leaves over 15 feet from the seating to the rear wall. Even giving the rear monopoles lots of room to breath from behind, I end up with about 14 feet from the rear surrounds to the listening position. This is more than twice the distance from the listening position to the fronts.

    Is there such a thing as too far back? Is there an optimal distance? If 14 feet is potentially problematic, I have an idea for having the rears hang down from the ceiling. Then I could place them anywhere I desire. Of course, the rear wall is greatly preferred.

    I greatly appreciate your replies. Sincerest thanks.

    Nick
     
  2. Robert*S

    Robert*S Stunt Coordinator

    Joined:
    Jan 7, 2004
    Messages:
    55
    Likes Received:
    0
    Hey Nick,
    I do not think you will have a problem with your rear surrounds 14 ft. back. Make sure you calibrate with a disc like Sound & Vision HTT or Avia to set your levels correctly and you should be fine.

    bert.
     
  3. Nick B

    Nick B Stunt Coordinator

    Joined:
    Dec 8, 2003
    Messages:
    65
    Likes Received:
    0
    Thanks, Bert. After reading an article via a helpful link provided by Chu, I agree. Given the innate room problems of reflection and standing waves, further back seems better. More opportunity for the sound waves to diffuse. Again, as you point out, all of this is dependent upon proper calibration. My DVE is on its way. Thank you again for your response.

    Nick
     
  4. CarlosM

    CarlosM Stunt Coordinator

    Joined:
    Nov 30, 2003
    Messages:
    64
    Likes Received:
    0
    wait a sec, nick -- you're going to only sit 6' away from your 50" tv? Does't that seem a bit tight? Keep in mind you may want some room from your front speakers and the wall(s) theyre near.
     
  5. Nick B

    Nick B Stunt Coordinator

    Joined:
    Dec 8, 2003
    Messages:
    65
    Likes Received:
    0
    Hi Carlos. Yes, it does seem a bit tight. But according to THX standards for HD viewing, 6' is what is recommended. Out of necessity, I will probably have to push back a bit, but hopefully not too far.

    My mains need room to breath as well, and 6' might not cut it for them either.
     
  6. MikeTz

    MikeTz Stunt Coordinator

    Joined:
    Mar 7, 2003
    Messages:
    146
    Likes Received:
    0
    Nick:

    Does your receiver or pre/processor have a set-up menu entry for the distance of all your speakers to the listening position? If so, just tell the pre/processor that your rears are 15 feet behind the listener and it will compensate (delay will be adjusted by ~1msec per foot).

    BTW I remember reading that audio will be optimized when the the distance of the listener to L/C/R speakers are equidistant and the angle of that isosceles triangle is less than 55 degrees (at the listening position, if you draw a straight line to the left and right speakers, the angle at the listening position should be 55 degrees or less). If this is so, then sitting six feet back of your speakers, your left and right front speakers should be no more than 66" apart from one another. Just another fun fact from the genetically miswired.

    MT
     
  7. Nick B

    Nick B Stunt Coordinator

    Joined:
    Dec 8, 2003
    Messages:
    65
    Likes Received:
    0
    Excellent point, Mike. Now I can quantify how far back from the fronts I need to be. Of course, this distance and the screen distance will be completely different! That's what makes this so much fun. Thank you all for your replies.

    NIck
     
  8. Chad Viro

    Chad Viro Stunt Coordinator

    Joined:
    Mar 1, 2003
    Messages:
    87
    Likes Received:
    0
    Nick, sounds like I am going to have the EXACT same room setup! is your room sort of L shaped by chance? I am having a hard time figuring out where to put my 5.1 side surrounds.

    Also, it appears as though I am going to be sitting 8-9 feet from my 57 inch tv.
     
  9. Nick B

    Nick B Stunt Coordinator

    Joined:
    Dec 8, 2003
    Messages:
    65
    Likes Received:
    0
    Hello Chad:

    No, my room is pretty much rectangular. It is 25x13. However, it is not perfectly rectangular because one of the 13' walls jogs back about 3' about half way across, kind of like:
    ____________
    l
    ___________l

    L shapes can be challenging. What are your actual dimensions? Perhaps some forum members have dealt with such a difficult room and have come up with some solutions?

    9' from your TV, if it is HD, sounds pretty far. I have heard recommendations of 3 to 3 1/2 times your screen height as the appropriate distance for HD. I did a search using "distance from screen" and found many helpful posts.

    Good luck, and let me know if I can be of any assistance.

    Nick
     
  10. Jamie Peters

    Jamie Peters Agent

    Joined:
    Jan 14, 2004
    Messages:
    38
    Likes Received:
    0
    I just took delivery of my Hitachi 51S500. My main viewing seat is 13ft from the screen. In all the theory I have read, that is too far but I have watched 2 or 3 DVD's in 540P and it is really a nice distance. I tried moving up closer and I didn't like it as well. So viewing distance is definitley subjective....

    Chad,
    I am also struggling with an L Shaped Great room. The wall the tv is on is 13' wide and the TV is centered. The opposite wall (behind the main seating position) is 20'. My TV is 25" thick so my viewing distance is approximatley 13' or 15' from the wall which leaves 5 ft. behind me. The wall in which the left surround would mount is 6.5 feet from the main position. The problem is with my right surround. Since the room is L shaped and the main listen position (MLP) is past the inside L corner, it is about 16.5 feet to the wall. I have the following questions if ANYBODY has any advice/experience....

    1. If my receiver has the capabilities to set distances to each individual speaker, can I TUNE the distance differences out of my surrounds? This is assuming that I use front firing speakers pointing in towards MLP and just a little behind?
    2. Since my back wall is only 5 ft away, it would be real easy to put them on the back wall but I have read this is not desired. Is this the case?
    3. If I use the back wall for my surrounds, would Bi-polar speakers work better?

    Thanks in advance for any help.....
     
  11. Jamie Peters

    Jamie Peters Agent

    Joined:
    Jan 14, 2004
    Messages:
    38
    Likes Received:
    0
    Anybody???
     
  12. Cees Alons

    Cees Alons Moderator
    Moderator

    Joined:
    Jul 31, 1997
    Messages:
    19,357
    Likes Received:
    293
    Real Name:
    Cees Alons
    Short answer: placing your surrounds on the backwall is OK.

    Some people like their surrounds to the sides, some behind them to the sidewalls, some to the backwall. It seems to be a matter of taste and there is NO theoretical background saying they couldn't be there. Place them somewhat higher than ear-height (when sitting). Point them either to your 'soft spot' (slightly higher). No, bipolars wouldn't be the choice for speakers in that position.

    About that 'tuning': if your receiver can set the distances (delays) for the individual surround channels, why not?

    Good luck,


    Cees
     
  13. MuneebM

    MuneebM Supporting Actor

    Joined:
    Jan 12, 2004
    Messages:
    621
    Likes Received:
    0

    Nick, can you please post the link. I am also forced to put my single surround back speaker on my back wall, 8 ft. behind my seating position.

    I agree with Jamie that distance to the screen is definitely subjective. My screen is 12-14 ft. from my seating position and that's how I like it, any closer just doesn't look as good to me.
     
  14. Chad Viro

    Chad Viro Stunt Coordinator

    Joined:
    Mar 1, 2003
    Messages:
    87
    Likes Received:
    0
    Does the Denon 3803 receiver allow you to set distances?
     

Share This Page