Novel idea for room mode selection

Folks, I had an idea (uh oh) for a room design concept I haven't seen proposed before. It seems like a good idea to me, but I'll be interested in opinions from all the experts here. We all know that room modes should be spaced evenly if possible, and start low enough in frequency to avoid large gaps between modes. But what about the idea of also aiming for room modes to not align with musical notes? For example, avoiding a length of exactly 20.55 feet because that aligns with A bass notes. So if you instead use 20 feet, the modes for the most part fall nicely between notes up to a few hundred Hz. I understand that room dimensions and their frequencies don't always correspond for various reasons, so that would have to be accounted for. And some bass instruments might not align with standard musical notes, such as a bass drum. And modes also have a finite bandwidth so it's impossible to avoid their influence entirely. But conceptually this seems a worthy goal to me. I could almost see rock & roll rooms designed to avoid modes in the keys of C, G, and E. :) Or even a Beethoven room that avoids coloring Bb and Eb. What do you all think? Has this ever been proposed before? --Ethan

Ethan Winer wrote:

We all know that room modes should be spaced evenly if possible, and start low enough in frequency to avoid large gaps between modes. But what about the idea of also aiming for room modes to not align with musical notes?

I guess you'd be pretty well f**ked if you were listening to a Frank Sinatra record then, wouldn't you. :wink: :lol:

I've been busy (since couple of years back), with adjusting simulation models in function of calculating the modal interference patterns on the musical scale in order to optimize speaker position and room ratios. I don't handle this public, but when needed can prove I did and sent (back then) temporary calculations and principles to 3rd party(s).

That's great Eric. And no need to prove anything. I believe you! :)

Eric_Desart wrote:

I've been busy (since couple of years back), with adjusting simulation models in function of calculating the modal interference patterns on the musical scale in order to optimize speaker position and room ratios. I don't handle this public, but when needed can prove I did and sent (back then) temporary calculations and principles to 3rd party(s).

Eric_Desart wrote:

I don't handle this public, but when needed can prove I did and sent (back then) temporary calculations and principles to 3rd party(s).

weren't you going to send me a DVD with all your secret files? 8)

I had another thought worth mentioning. If a room mode is very close to a standard music frequency but not exactly the same, it can tend to make some bass notes sound out of tune. For example, if a room mode is at 112 Hz and the bass plays an A at 110 Hz, the bass note will excite the mode to ring and the ringing that lingers is sharp. I suppose for modes that are sufficiently damped this is less of a problem. But it's hard to get adequate damping at the lowest frequencies. --Ethan