Originally Posted by Luke Kamp
Originally Posted by Gorilla83
Luke - When pushing some clips at full tilt there were definitely some complaints from the drivers and I had to back them down. They may or may not have been audible from all points of the room, but I did have to back the volume down at times. Granted these were at or above reference at this point, but there were a few unwelcome noises for sure.
Again regarding the HPF being engaged on only one channel - like I said before this was just my *assumption* as to why the curve was looking drastically different. The next day when playing around this was the only explanation I could come up with - this may or may not have been the culprit of the issue. I wanted this to be clear for the group as we didn't have any of the settings saved to review post-event so all we can do is guess at this point.
As far as power below 20hz - I don't own any passive sealed subs to test the ultra lows, but I can tell you I've run sweeps up to 110+db with my caps and solid extension to 13-15hz. This includes some room gain of course but it does not appear to have a built in HPF at this point. At 10hz? Maybe, and I'll probably find out once I build something sealed.
Hope this helps clarify some things.
Thanks for that. I am always just wondering the "why?" behind perceived results. Mistakes happen when you have a huge one day undertaking such as this, I think there would have been a large difference in the sound had the hpf's been setup correctly. Is it possible that the hpf issue was on the lms and dayton's as well? Upon looking back now you guys stated that the different box sized lms's measured pretty even. Could it have been that the hpf was on the larger enclosure therefore making them appear to roll off similar?
For the very last bit of insane level listening with the Caps (post breaker-pop), I was next to Andrew and was noticing what was most likely amp clipping or possibly driver complaint (no clacks or anything that offensive). At the levels being played, we would have eventually reached clipping regardless of the settings. popalock's demo was a great example of this with his laser light show of clip lights.
While this wasn't as big a deal in the first music pass at the matched 50Hz level playback, it should be obvious that the iNuke clipping was a huge impact on what was heard from that point on.
For the comments on the subjective articulation between the SubMersives and Captivators when we let loose on the volume, this was a result of a conscious choice/trade-off I made for the demo. Many still greatly underestimate how important the native (ground plane) frequency response shape is and how it interacts with the room. After myself actually grabbing earplugs during popalock & gorilla83's jam sessions, I decided to use the 15Hz (program 2) vs. the 19Hz response mode. The difference is in fact just a precisely shaped 3.5-4dB shelf which shifts the entire bottom end response to the left on a graph, but as anyone with a SubMersive can attest, this seemingly subtle, but wide band response change is quite audible.
I chose this setting to allow more deep bass energy without as painful a playback level, as I listened through the entire SubMersive demo without earplugs. The combination of the +8dB sub calibration, mostly flat if not rising LF response and peak in the mid 20s makes for a very impressive home theater sound, but will almost always thicken up the sound a bit, especially with the subs so elevated from the mains. This choice of having much more bottom end at the same playback level also means the system will find it's VLF limits at a lower level than if it rolled off much sooner.
So for a case where there was say a 10dB drop in the subwoofer from 50 to 20Hz, the 20Hz level was still only 2dB below the main speakers, and a sub can play subjectively much louder in the 30-80Hz range in such a situation. What you end up with is in fact a large ramp up from the main speakers' level to the 80Hz range, and then a gradual taper back down to the main speakers' level in the upper teens. Yes, that will certainly have a lot of punch and upper bass impact.
Having been to a handful of such comparison efforts now, I really think a much more enlightening event would be some listening experimentation and understanding. I regularly see misunderstandings of what type of behavior or frequency content is responsible for various perceptions, even with the spectrographs posted. "Low and loud" is more often 25-35Hz than the VLF content which is much more responsible for weight, punctuation, scale and shuddering. Most of the more impact sensations happens above 35Hz. I suspect many would benefit greatly from picking a handful of scenes/songs that include different desirable bass qualities and effects and listening to them over and over with all sorts of different filtering applied. In particular listening to maybe 1/2 octave wide ranges at a time or progressively moving a 4th+ order filter lower (eliminating the upper bass octave), and then bottom up.
If you want some good insights into what contributes to different subjective effects go back and read through Keith Yates' Way Down Deep report
. Instead of looking for what was the best performer, instead read through Keith's listening comments and then see how that correlates to the measurements and waterfall plots. Keith is a very experienced listener who knows right where to grab at an EQ direction from listening, and while the commentary in that report was intended for the Stereophile Guide to Home Theater crowd, it's worth a thorough reading.