Subs: sealed vs. ported

I don't know much (anything) about your Yamaha, so wouldn't be able to offer any advice on settings. I suspect you've fiddled with bass settings "per mode". I know some AVRs offer the option either a basic crossover to the sub, or summing the low frequencies of both the mains and sub. This latter setting can cause bass bloat, especially if your mains aren't up to the task.

Best of luck with your setup!

I ran the AVR's room measurement program. Initially when the mains were still set on 'large', I had no sub on 2 channel, but changing them to 'small' brough the sub into play. There are room problems, watching a movie last night I was getting spurious vibrations from the front wall and fireplace area, and something on the side wall was vibrating too, so I have to tracking down and tuning to do.

I do consulting in sound and vision. In the past I did sell a lot of Rel sub. Also the more expensive ones. I always had stereo highend systems without sub's. For me they were too slow. At this moment Rel is not that big anymore. In europe there are many brands which are superior in subwoofers. Many clients bought other brands and they are all much more happy. For stereo I only found a few fast enough. It needs a 15 inch unit, ( Not made of paper), big amp and sealed. And only one speaker unit on the front side. With Audessey Pro you can get fully stealth low freq. I never thought this was possible. Using it to 120 hz is bringing it to a new level. The Old rel subwoofers like stadium became very noisy above 60 hz. because they were slow like hell. I use a Platinum PLW-15 subwoofer from Monitor Audio. It is so much faster compared to Rel. I would not even dear to sell it to my clients anymore.