Quote: Originally Posted by DanDan memphis, despite an odd entrance some nice ideas. I have pondered the designs of panel traps for some time and I come up with pretty much the same intuitive thoughts as yourself. However I have not actually tried and tested my theories. I have stuck with broadband. I am sure all of us would love to see your ideas tested in some way. Ethan in particular, walks the walk in this matter. When he says cling film or other light plastic works you can rest assured that he has tested it. Furthermore he must have tested bass performance with the membrane in front and behind, and concluded it works better in front. I would have guessed it would be about equal, given the long wavelength of bass, and it seems I would have been wrong. Test and Measurement absolutely trumps intuition here. FYI I personally don't like the HF bounce of plastic or foil. If I were to construct a LM trap I would leave a gap between the fibre batt and the membrane. I would also use a membrane intrinsically dampled, eg. lead impregnated vinyl or rubber sheet with a layer of HF absorption on the front This of course is a classic design, tried and tested. I would point out that since it is actually airtight it does not allow an overall spectrum of sound and is definitely not broadband. DD It was odd. Must have fallen straight off a thread with a shill for the baddies on it. Ethan and Frank are probably the best resource for data so far. After Ethan's film, I OWE it to him to buy a pane from him one day whether I need one or not. It's cool, I'm not married to any idea I may have, just dating. Till I build my new room, I can't test or construct. Maybe when the snow melts.