XLR and DBS (Audioquest)

DBS is BS!

DBS is an absolute must on the AudioQuest cable line, irrespective of how you have the cable terminated. The effect of engaging the DBS is quite obvious however you will only notice this if you switch it off (i.e. unplug the small DBS jack) as it can take 48-72 hours for the field to fully form. Without the DBS my AQ WEL cables sound rather edgy and thin, with the DBS working fully there is palpable solidity to the image and uniformity across the frequency range. I own both RCA and XLR terminated WEL -- which of the two is better will depend on the equipment used (I just discovered that the balanced outputs on my DCS stack actually sound worse than the single ended so am switching to RCA in that application). Finally AQ will reterminate any of their cables (at cost) should your needs ever change

They are worth it and lower the noise floor.  The end result is similar to what @folkfreak mentioned.  However, I'd try them in your own personal system if you can. System synergy and subjective preferences come to play.  As with a controversial cable topic like this you can be sure the pessimistic will also chime in as they already have. 

I have a pair of AQ. Earth interconnects with DBS and XLR termination. All I can say is these cables sound pretty darn good in my system although I can't attest it to the XLR termination. I tried a comparison a few years back with Purist Audio Museaus, both XLR and RCA terminated. one pair each. My CD player/DAC had connections for both so I could rapidly switch between the two to listen to the same cut. I really couldn't tell any difference between the two. Maybe my system just wasn't up to task. I could see where some would think the XLR would sound better because in my comparison, the XLR connection was a tiny bit louder than the RCA connection. To people who are not aware of this, the XLR could be perceived as the better sounding cable. being a   bit louder could be heard as "more resolution." But we all know that wouldn't be the case...