Cube Audio Nenuphar Single Driver Speaker (10 inch) TQWT Enclosure

@abd1  The unthreaded versions have a flat surface. 

I used this or something similar: 3M VHB double sided.

https://www.theclip.com/store/3m-vhb-double-sided-adhesive-small-round.html?gclid=CjwKCAiAkJKCBhAyEi...

@david_ten ok I get it. I bought the threaded ones, oops. Thanks. 

If not returnable, you could cut the threaded section. If it is an insert, you can remove it and use the adhesive disc (which will cover the insert hole).

This is an amber alert regarding using resistors between positive side of speaker cables and the VR L2iSE output terminals.  I just removed my Dueland 1ohm resistors--put in place to lower dampen factor--and realized a big jump in sound quality, specifically in the highs which improved imaging, depth and detail. This was not a subtle change. When I originally installed the resistors I was using Synergistic Foundation speaker cables and the improvements the resistors made was tangible, easy to hear.  But when I replaced those cables with Shunyata Alpha NR2 cables I simply installed them with the resistors assuming the same benefits would apply.  I was very wrong.  For whatever reason, the Alpha's increased resistance, the different technology Shunyata uses, whatever, the resistors actually hurt the SQ.  So vinpic and others who might be considering using resistors in this manner, please be aware that the improvement may heavily depend on the type of speaker cable you are using.  When I installed the Alpha speaker cables at first with the resistors I heard so many changes/improvements that I didn't think to try them without the resistors.  I only removed them now out of simple curiosity to be able to talk about their benefits.     

Stephen,
What you discovered makes sense. Your two different speaker cables could have relative meaningful differences in their gauge, resistance and capacitance. These variables could definitely affect/ impact the total amount of the damping factor (DF). The final DF value factors in speaker impedance and speaker cable contributions (And obviously amplifier output impedance) . Just goes to show how valuable our ears are. You clearly heard a change.
Charles