[rockadanny]

I've been fretting over a 55-65Hz bass null (down 8-10dB) for a while. Speaker and sub (2) placement is limited so moving them around only a foot this way and that had no effect. Changing passive in-line filter values to mains and sub cross-overs had no effect. Nor did messing with sub phases. So I took two GIK 244 panels down off of the (too near) wall behind my head and schlepped them around my two subs while watching my SPL meter. It turns out that only one sub is the cause. Unfortunately the panels need to be placed in a spot such that they'll not be able to live there permanently. I'll just have to drag them out for critical listening and store them in a nearby closet for the remainder.

Anyway, I am THRILLED to have smote the dreaded null beast! Woo-hoo! Die you bastard null! Die!    Ha ha ha ha ...

Here is a pic. The black sub is under the floor lamp and the panels are behind the lamp, out in free space.

[rockadanny]

Brian or Glenn or Ethan or Schmoe - Any more asthetic options or alternate ideas? It takes a full two-panel widths for desired result. A third panel only helped slightly (raised response additional 1/2db) so to me it's not worth the additional panel. But two work great!

[bpape]

Did you try it against the hall wall?  Or, does it need to  'cut off' the wave out into the hall to be effective?

Bryan

[rockadanny]

Hmm ... good thought. I was so excited when I discovered this solution I didn't think to try them up against that wall (several feet behind the panels). I will try that to see if that works as well. Good idea Bryan. Thanks.

And I must say I definitely prefer two (tamed) subs in my room over the one. Sounds great.

[bpape]

It may or may not work completely but should still help some.  Where you have them, it could be a combination of the 'blocking' of the hall coupled with a more tuned type absorption based on the distance from panel to the hall wall vs. the wavelength of the null in question.

Bryan

[rockadanny]

Placing the panels on the further wall helped a tad but not much. I guess it is more a matter of blocking the opening. That wall where the sub is does not go to the ceiling. It is free standing with cabinets on the other side which is the kitchen. 60Hz wave is around 20' long so I don't understand completely. I wish there was a kind of light which allowed you to actually see certain freq. sound waves. That would be way cool and make things soooo much easier.