I have a relatively new Denon X3400H which replaced my old Denon X3313C in March.
Sick of the lack of bass from my Klipsch subwoofer I upgraded to a HSU sub a few weeks ago.
It turns out that my lack of bass may not have been the sub but the receivers themselves.
After getting the sub set up I flipped on the receiver one day and played something and noticed the bass did not have the punch I expected. I wandered over to the sub and even though the green light was on indicating it was receiving signal from the receiver there was nothing happening there.
I cranked the volume on the sub to max and I could just barely detect sound. That volume on the HSU should have shaken the house apart.
I unplugged the sub from the wall power (mains) and plugged it back in and suddenly I had all sorts of base coming out of the sub again.
This scenario has happened to me several times now. It happens with both the Klipsch sub and the HSU sub.
The power switch on the subs are both in "standby" mode so they turn on when the sub starts sending out LFE data.
I have the sub connected with a good Monoprice RCA cable (one of the RG6 types shown here https://www.monoprice.com/product?p_id=2683
.) I even swapped to a new cable with no difference.
I am convinced that this problem also happened with my old receiver too. That Klipsch sub has more punch than I recall when I have it hooked up and running and know it's running properly. I was expecting it to always be there putting out bass when it wasn't and maybe not for years. I cannot test the old receiver as I sold it.
When it's working the opening of Edge of Tomorrow is amazing. When it's not, it's totally underwhelming and that's how I discovered this problem. The rest of my speakers are pretty good but not that good.
Any theories as to why this keeps happening?
I have no sub volume adjustment happening; it's off on the Denon.
My crossover is set to 90Hz on the Denon.
All speakers are set to small on the Denon.
The bass output is all + LFE.
All I do to "fix" this problem is unplug the main power on the sub while the receiver is powered on, wait about 15 seconds, then plug it back in. Voila! - bass is back!