Artto - Room design

[sheltie dave]

Artto,

at some point in the not far distant future, we will be building an addition to our house and a great room will be in the works. Does PWK recommend any special room dimensions for consideration, or did he leave that up to you?

What type of ceiling would work well with the great room? We are looking at oak floors and a rafter with oak beams to optimally use the available space, but keeping costs down would also be nice.

We have a set of cornerhorns, three Belles, and three Heresys, so we are well set with speakers at this point. I would like to get the great room planned out so we can build the new extension based on these needs.

Thanks for any suggestions!

[artto]

Dave, pretty much all of your questions are answered in my thread. A lot of the performance obtainable from any speaker, more so with Klipsch Heritage series and the Klipschorn in particular, is dependent on a number of factors.

Yes, PWK recommended certain tolerances to the room proportions. Actually he got it from a paper published by R.H. Bolt in the Journal of the Acoustical Society of America. Its based on what is known in mathematics as The Golden Mean or Fibonacci Sequence. It works well for closed systems, which of course, most rooms are (the walls dont move around as in dynamic systems).

The length to width ratio should lie between 1.26 & 1.62

A ratio of height to width to length of approximately 1: 1.26: 1.59 is preferable to minimize excitation of room modes caused by the room boundaries. Klipschorns, because of their corner design, are capable of exciting any and all room modes, so its important to minimize them to obtain the smoothest frequency response, especially as the frequency goes lower.

The room should also be reasonably large. Khorns need room the breathe. Even on an 18 wall they can seem cramped, especially with a center speaker like a Belle.

A room dimension to avoid is 18 13/16 or close to it, or multiples thereof, as this is the wavelength of a 60Hz tone & will accentuate any 60Hz electrical noise.

Avoid the typical acoustic tile used for ceilings. It has a rather narrow frequency band of absorption. Good for office noise, but not sound reproduction.

Because of the way Khorns disperse the sound (angle of coverage), and because of the slight delay between the tweeter & mid drivers, the floor really should be a heavy carpeting, ceiling hard surfaces. Beams are ok, but you really want to avoid early reflections to the listening area. More absorption in the rear of the room & rear sides.

Standing waves tend to pile up at the rear corners & rear wall/ceiling intersections. Large objects & bass trap sound absorption here will make the low-end more pronounced, deeper & with better detail & definition at the listening position.

Ideally, the idea is to achieve BROADBAND diffusion & absorption.