10" self powered sub-woofers.....

@doctors11   My music room is carpeted.  I am connected with standard RCAs at the moment but that does put some pressure on them and I can't pull the spike covers and set the sub into the carpet and underlying concrete.  Probably should not even have them connected this way but I was careful.  Just order up a pair of Audioquest 90 degree RCA adaptors and an Audioquest 90 degree IEC adaptor on the same page as the sub...  ...  together it's maybe another $40.  You will need the 90 degree IEC if you plan on upgrading the cord anyway. 

@doctors11  An update for this Saturday...... April 24th... 90 degree Audioquest RCA adapters are here and the sub is now on Blue Jeans Cable LC-1, 3 meter length. Admittedly, not my first choice but an affordable one until I have an opportunity to acquire my first choice, LOL, pre-owned. Audioquest NRG-X3 cord is due in today as is an Audioquest 90 degree position 1 IEC adapter. I plan on using 10 - 20 pounds of additional top cabinet weight to make sure the sub is very solidly spiked to the ground. It currently is on its rubber spike covers and has maybe 10 hours of the recommended 50 hours of break in time. If I was going to comment at this point I would say the articulation of double bass riffs up and down to the bottom (and organ) was completely superior to the NHTs. I also feel I’m getting very close to fully dialed in at this point and if I can match them to the roll-off of 30 year old 8" bass drivers in my Acoustats you can match them to anything. Presently set @ -20 db, 40 hz third order low pass, 20-30 hz level at +2 db.... everything is adjustable by the db, hz, and phase angle degree Very worthwhile for my listening so far and will only get better when I get it off the rubber feet...

Thank you so much @midareff1 for these write ups. It's been hard to find many customer reviews with well thought out details like yours. I value tight accurate bass over all else and I have space constraints so as of now this is a clear first choice for me. I will be using the room correction and upon further reading I was impressed that they recognize that android phones differ greatly in their built in mic, so they have software that measures your individual phone mic before proceeding to run the room correction. Pretty cool!

@doctors11    Thanks for the kind words.  My area of interest is the same as yours.  I want to follow a double bass riff up and down the scale to the bottom with definition and reproduce anything that a regular acoustic guitar and piano can do at the lowest hz notes.   In my case this sub is for the low octave from 20 hz to 40 hz with my woofers picking up there for basically 2.5 octaves to roughly 250 hz where the woofers start the crossover to the panels.  The woofers were originally rated at -3db @ 30 hz but I'd say it's more like 40  hz now and the ML is adjustable by the hz and by the db so the only catch point is listening to a variety of recordings so one albums mastering techs' preferences do not become your settings. .  IEC cable in hand and waiting on Amazon on the adapter.

@doctors11 I guess this is the last post by me on this subject unless someone wants to PM me about some aspect of this I haven't either posted on or been clear about.  Sub is now up on spikes, Audioquest 90 degree RCA adapters, .Blue Jeans Cable LC-1 cables ..Audioquest NRG-X3 power cord, on it's spikes + some additional weight for the spikes to couple...  some additional lead weight on the top to help the spikes get solid through the carpet......   no consequential changes anticipated.
Karrin Allyson's In Blue Album.....   Qobuzz ...   beautiful.  Lots of low double base, some organ and low piano notes...   all articulated beautifully.
Patricia Barber's A Distortion of Love Album....  also Qobuzz  beautiful ...  Lots of low double base, some organ and low piano notes...   all articulated beautifully. 
If you want a ghetto banger sub this may or may not be for you...  I have no idea.  If you like jazz, club and lounge presentations and such I can tell you this sub will follow a double bass riff to the bottom that the double can play.. 

Sub + decent power cord + decent cables and RCA adapters...  a $1100, maybe a bit more....  what's your bottom octave worth?