Speaker placement formula

I tried looking in the old threads and I didn't find what I am looking for. Hopefully this isn't a subject that has been asked about too much.

I am looking for a formula (I'm almost positive Martin Logan prints one in their manual) that calculates speaker placement in the room. It takes into account ceiling height also. I know about the whole equilateral triangle, but I think Martin Logan's is different. And if I'm not mistaking, ML's is a pretty common formula? I could be wrong. If anyone could help, that would be great. Thanks.

Try cardas.com or immediasound.com. Both have great papers on what you're asking...
Funny you should post this...I just went to Brystons website to get a formula for that today...I think it is supposed to be sort of a generic formula...it is as follows

(room height in ")x(.618)= distance from rear wall*
(room width in " / 18)x(5)= distance of tweeters from side walls

*the diagram showed the distance from the rear wall to be to the back of the speaker.

hope this helps,

Formulas are great but you can only use them to get a very general idea. Real rooms are a lot more complex acoustically than most formulas take into account. Few allow for furniture, wall/floor surface type, much less the polar radiation pattern or source impedance of your equipment which is apparently important in determining room response. Art Ludwig and Linkwitz have interesting stuff to say on this topic and are worth a look if you are looking at your room. www.linkwitzlab.com and www.silcom.com/~aludwig if your interested.

Good luck,

Sincerely, i remain
You might want to buy a copy of F. Alton Everest's book on recording studio design (sorry I don't remember the exact title). It's pretty inexpensive and gets into the dynamics of the total room. Optimum speaker placement in a rectangular room depends on a number of factors including 1)wall, ceiling and floor composition, 2) room dimensions and 3)listener position (plus speaker design, furnishings, etc.). I studied the heck out of it since I'm building a new house around a sound room (sounds goofy, but ...). The sites referenced above provide great food for thought and background. If you really want to dig into the factors around this, you might want to read Everest. There are a number of formulas in there that cover the topic. Trust your ears and have fun experimenting. Cheers.
These two sites might be helpful:



Here is another one for ya

Oh yea and one other I forgot to give you, Its a software program you can download for free and does all the math for you, Check it out.


Also Home Theatre Setup

I like the ones at www.cardas.com
The cost is $50.00
There is also a company in NH who sells it for $50 plus $6.00 shipping - this was in the latest Audio Critic or Audio Xpress - can't remember