Need help with room and speaker setup, big dip from 250-80hz


I have a very small and odd room.  The room itself is 9' wide by 10' long with 9' ceilings.  The wall directly behind my head is only 3' tall, above that it opens up to my family room and kitchen.  I have the speakers firing down the 10' length.  The speakers (Sonus Faber Guaneri Evolution monitors) are toed in directly at my head, 3' from the front wall, and 1.5" from the sidewalls.  I have bass traps in the corners, absorption at the 1st reflection points and ceiling, and a mix of absorption and diffusion on the front wall.  My listening chair is right up against the short back wall.

I just did a quick measurement of my room using a cheap RS SPL meter and some test tones.  It seems I am -6db at 630hz and 250-80hz.  Any advice what I can do to help alleviate these dips?  As you can tell by my room dimensions I do not have a lot of flexibility.  Thank you.
128x128tboooe

Showing 1 response by sbank

This may not true any more depending on the vintage of your RS meter, but they used to be known to need a well documented adjustment to results to adjust for variations in its ability to measure at differing frequencies. Search online and you'll find a table that tells you to add or subtract from each result (e.g. "at 80hz +3db"). I think the adjustment is based on limitations of the built in microphone. 
Squarish rooms are tough, although with a 3' tall half wall, higher frequencies might act as if you are in the "bigger room" ignoring the half wall. Many speakers manufs. suggest a diagonal setup in squarish rooms. Could be worth a try if everything else mentioned doesn't work out to your satisfaction. Cheers,
Spencer