Have a pair of REL S3 HO and they don't produce enough bass


Hi all-

Just picked up a pair of REL S3 HO subs to work with both my 2 channel system and my home theater. The high output speaker connections on the subs go to my 2 channel system and plug into each mono block amp. The LFE connection from each sub hooks into my Anthem 720 receiver for home theater. 

For the 2 channel system it seems to work well. Nice low bass helping out my Focal Kanta No. 2 speakers. 

However, for the home theater system, they just don't produce enough bass. I have to turn them ALL the way up using the sub's LFE volume control, AND turn them all the way up in my Anthem receiver settings to get any semblance of home theater bass. I know this isn't normal, so something has to be either wrong, or the subs just aren't meant for home theater use.

I was using a pair of SVS 12" subs and man those things rocked. However, I picked up the RELs so I could integrate them with my 2 channel system as well, something the SVS' could not do.

Any idea what could be the problem? 

A side note: I have NOT run Anthem's ARC program again since buying the RELs. Perhaps that could be the issue, but I didn't think it would make that much of a difference. However, I could obviously be wrong. :-)

Thanks!
sadcaper
One additional question.  Are you connecting the REL subs in the exact same way you connected the SVS?  If you did a change in configuration, it could affect the way your Anthem routes bass frequencies.  Also, I would agree with batman's suggestion to re-run ARC.
No fix yet for this. I ran ARC again and same thing. I spoke with Rel and they suggested starting over again. So I’m just living with it for now. It’s adequate i suppose, but it’s not “great” which it should be. 
The REL S3 is designed for music. REL designs subs specifically for HT. In my opinion JL Audio subs work better when used for both music and HT. SVS is very good for HT.
Play with the HI/LO level adjustment...1 click at a time. I can quickly fill my room with more bass than my neighbors can stand with 1 S5 SHO. It does take some time and tweaking to get it dialed in but the results are worth it.