Originally Posted by MKtheater
Sorry man, you xs30 is probably about the same as the chase so if you think that it has puffs of air then you have not experienced a true 10hz theater yet. .
I'd say you are right about that, or pretty close anyway on the low end. I would love to do some accurate testing in a theater with reference capability down to the single digits. However, I can only go by my experience and that of people who have done what I consider accurate tests concerning how noticeable the really low stuff is. Since my XS30 was flat to 10 Hz to over 100 dB in my room, it has a huge advantage over the XV15 below 15 Hz. I went to dual XV15's which of course puts the XS30 at a disadvantage. However, the XS30 should have made some of that difference up with its greater output down to 10. Alas, that was not the case. The dual XV's have literally triple the tactile effect on movies over the single XS30. Of course, the drivers I have are the upgraded versions compared to the XS30.
I am open to the possibility that I may not be right, but I think that people having flat reference capability to 10 Hz and below is simply increasing their clean headroom where it is really noticeable....above 15 Hz. I would not mind at all if I was wrong, and again, would love to experience reference level single digits, and do some HPF's and LPF's on various scenes to compare the effects. I would also want to rule out the possibility of very high level 2nd and 3rd order harmonic distortion being produced and noticed, rather than the fundamental. From what I understand, extreme excursion at low frequency is a lot more likely to produce high harmonic distortion.
Part of what reinforces this(to me) is that often times, in blind testing, people are not able to tell which sub extends lower..ported or sealed, and the ported, or even the horns, have more noticeable and tactile effect. This would surely almost always be just the opposite if single digits and low teens added a lot of effect. It makes no sense to me that subs with sharp drop offs below 15 Hz are equally or more impressive on LFE, in blind testing, than subs which extend flat into the single digits. In my mind, if it was that noticeable, the single digit subs should destroy the horns and ported subs in listening tests on lfe.
So MK, I am not trying to argue just for the sake of arguing, but I hope this helps explains why I have the opinion I do. Again, I would love to, and do plan to, explore this area further as there seems to be controversy regarding "how low should you go". Although I don't remember who it was, I do also remember reading a statement from a forum member who LFP'd his reference level single digit system at 15 and basically nothing happened....the drivers went crazy..the output was measured...just not very noticeable.
So again, not trying to get in a pissing match or anything, I just have not seen much yet that convinces me in a factual, scientific way that below 15 does much. In other words..an argument such as "I am flat to 6 Hz with 16-18" subs and it is way more impressive than when I was flat to 15 with two ported subs" does not prove much to me, other than that perhaps the extreme increase in output over 15 Hz is perhaps where the difference lies.
I do remember a G2G where a HPF was put in at 18 Hz and was easily noticed. I would expect this to be the case as 16 and 17 Hz are VERY tactile in my experience. I would like to see this done at 14.