Pondering REL and Dynaudio subwoofers.

I will vote for the Dyn sub. I have an 18S, not the sub 6, paired to C4’s. They are mechanically identical - the firmware is different and they do not have grills. I went with the 18S because I got it new on a holiday offer of £1k and the sub 6 was £2k, and I had not tried it out yet. I will replace it with a pair of sub 6’s sometime during the summer for aesthetics and symmetry. 

The sub 6 is easier to match. It took me five minutes to match the 18S. It has a built in 40hz pre-set which suits me fine. After that  it is just a matter of volume matching and placement. 

The Dyn subs have a 3 millisecond delay (about 6 feet) so easier to place than most subs. I am not sure about the Rel. I have had Velodyne, JL Audio, and SVS subs. imo the Dyn is the best of all of these. 

As with anything else, this is subjective and what matters most is what you like in your room. I would recommend trying them both out and that way you make the best decision. This also allows you to kill the ’What ifs’.

Cheers. 

Thanks @gotolondon2 ,good to hear from a Dynaudio sub user, I'm not very flexible on where it would sit, Center in line with the Heritage specials.  but this should work out.  My listening space is somewhat unconventional, i'd add a picture but I'm not sure how did you do that.  

Regards 

@grantgg Have you tried isolating the issue by using line level signal? I know REL highly recommends using speaker level for "x" reason but this is probably an easy issue that can be fixed. Unless is amplifier issue for the REL which is less likely, I would check how you ran your cables. Signal and current should never be run in parallel unless is a balanced signal. 

If you already like the integration with the REL sub then is worth keeping it unless you looking for something better. 

Have no clue if this will work but   
https://share.google/QWXeSgnx2U3gtt1tI

not having it connected to the amp might be the answer

@highend64 Yes, switching to low level, or a line level, would resolve the hum problem, but as you point out Rel much prefers the high-end connections.  In some testing I did, it was apparent that the high-end connection sounded more responsive, faster.  I didn't want to spend that much for a sub and not take advantage of it's full capability.

Same with going with a wireless connection, would fix it, but degrade its performance. 

Thanks