This happened twice so far with my sub. The last time was last night, I was watching Iron Man on bluray and during the beginning of the scene when he flies over to the town he was captured in wearing his new red/gold suit and lands, it sounded like my sub farted, literally. I got a little worried and automatically lowered the sub output. I wasn't watching very loud either, about mid level.

I have a Denon AVR-1909 receiver and used Audyssey to set all my levels. I was using Dynamic Volume on Evening level at about -25db. Is it the dynamic volume that's messing it up? Is there another setting that could be doing it?

I'm pretty sure it's just that movie. There is lots of bass added in center channel(especially in sonic boom scene) and with that info and rest of channels bass re-directed to sub may cause distortion(or port noise) in reference levels.

Btw, i now remember that some other people here did have some similar problems with audyssey and denon amps, (or was it onkyo) with incredible hulk sonic cannons scene with bigger subs(svs ultra).

the thing that worries me is that i wasn't even listening that loud. If I can confirm that a setting in my Denon is causing the SW output to be overly exaggerated for some reason (maybe due to dynamic EQ/Volume) I'll definitely want to change it.

The sound felt like it could blow the sub if it was any louder.

the thing that worries me is that i wasn't even listening that loud. If I can confirm that a setting in my Denon is causing the SW output to be overly exaggerated for some reason (maybe due to dynamic EQ/Volume) I'll definitely want to change it.

The sound felt like it could blow the sub if it was any louder.

You should check out the last few pages of the Audyssey thread under amps/receivers. You are not alone. I've had the same issues with my Outlaw Audio LFM-1 compact. Part of the problem is having smaller drivers they can be easily overdriven. You can mess with the sub level and the LFE level. Also, the DynamicEQ level can be controlled by lowering the source input. Because you have to turn it up after lowering the source it gets you closer to 0 quicker and less DynamicEQ is applied (it doesn't apply any DynamicEQ at 0).
So you might try bumping the LFE level down a bit and lowering the source level if you are using DynamicEQ.


A side note, I also had problems because my sub wasn't plugged into the high current sockets of my APC AV HT15. I still have headroom issues, but not nearly as much as before once I figured out my mistake. So, if you are using a cheap surge protector or power strip for the Sub I'd try it plugged directly into the wall. This really helped my situation.

Others have reported a boost in the lower frequencies (<20Hz) that are happeing because of the steep roll-off of their sub combined with the room environment.

I've decided to upgrade and ordered a MFW-15 ($200 off right now w/ new amp to solve the older amp issues). So, I shouldn't have this issue anymore.