Subwoofer matching


I was all set to pull the trigger on a pair of REL subwoofers.  These would be used with my Avangard Duo’s and Pass Labs XA 60.8 monoblocks.  My main music is Rock, Jazz and Blues.  I have been given advice by a few people now saying the 107 efficiency of the Duo’s will make it very difficult to find a matching paint odd subwoofers.  Feed back I have been given is “... it will take a powerful subwoofer to be able to match the output levels of your speakers“ and “The only REL model that may work for this application will be the 212/SE, which has a very powerful amplifier that will allow it to blend well with your speakers.”  A pair of REL 212/SE is a budget breaker for me.  I am in not position to judge if the advice is correct or not.  Does anyone have experience negating a pair of subwoofers to a highly efficient speaker?
chilli42
How many is much more important than which ones or how expensive. In other words, regardless of your budget its better to spend it on 4 than 1. Put another way you cannot find one sub that will be as good as 4 that cost 1/4 as much each. Search Swarm or distributed bass array.

System matching with 4 is a non-issue.
I'd suggest placing a phone call to REL and asking their opinion. REL customer service is very good.
Why not use the Avantgarde subwoofer?  It's specifically designed to work with their horn loudspeakers.
Chilli, Any subwoofer that can match the volume you like to listen at will be fine. Most of us rarely listen over 95 dB and any pair of 12" subwoofers will do that easily. They all have adjustable gain. You just adjust it to match the output of your main speakers. It will require more power to reach the same volume but all the decent subwoofers are equipped to handle that. The 4 10" drivers you get with the swarm system will also do just fine.
So, unless you listen at 115 dB any decent subwoofer can be made to match your system. You are right to start minimally with two.