I'm not certain this issue is or is not a listening level issue. I would be much more convinced that Funk is falling victim to room modes in the 40-50Hz region.
I have NEVER seen a measurement from ANY room EVER (I hope you're getting my point with the use of CAPS
) where the frequency response will be flat from 100Hz and below. You'd have to have the perfect shaped room dimensions which I certain none of us have. Therefore a flat response without EQ'ing or heavy room treatments is just not possible. Low frequencies are very influenced by your room and speaker placement.
If we can establish that the frequency response below 100Hz is very uneven, then listening at lower volumes will only make the issue more apparent. The louder the speakers are played, the less obvious the issue will potentially be, but if you know the music it should still be observable.
Take a look at this graph of my HT2 TL's measured at my listening position (RED=RIGHT, BLUE=LEFT):
I think we can all agree that Salk doesn't produce speakers with this kind of frequency response.
As long as we can agree on this, my room has to be influencing the overall response. While my HT2 TL's measure better in my room than any other speaker I've owned, the measured response below 100Hz is remarkably similar amongst many of the speakers and subwoofers I've measured in this room. I can only conclude that my room is influencing the frequencies more than any other factor.
In every case, my room creates that ~105Hz dip where you can see both speaker couple to the exact level. This has been true for any speaker I've measured in this room. Also, in every case, I get that ~38Hz bass peak with any speaker or subwoofer I've measured in this room.
Ever listen to some songs that sound weak in bass and others that are very strong? If yes, these are obvious signs that your low frequency response has peaks and valleys.
Since I have no way of EQ'ing my main speakers (and I don't want to), the only solution I've found for my issue is to run an EQ'd subwoofer. EQ'ing low frequencies doesn't create any audible noise issues like can happen with upper frequencies, so I don't take issue with doing so. The first time I heard my setup with an EQ'd sub, I was shocked. No more was there this large difference between songs with little or heavy bass (sure there are some differences, but it's not like I was used to hearing). The bass sounds much more articulate and the rest of the frequencies don't suffer from bloated bass being played. The subwoofer blends magically to the main speakers and does not make itself noticeable at all. And here is the all important comment:
the bass sounds balanced and present even at low listening levels. I may be off in some of my comments and observations with some of you more knowledgeable audio guys, but no matter what anyone says, I know what I hear.
This is only my opinion and as always YMMV.