So I have only recently connected my Triton Twos with dedicated LFE cables from my Onkyo TX-NR929 receiver (which is brand new) and the sound of the bass is astronomically loud!
The test signal sent through the levels calibration screen booms at 0db on the subwoofer channel.
I have turned it all the way down to -15db and the dial on the back of the Tritons to the lowest setting and the subs sound a lot better.
But I'm concerned... Why are the levels so high at 0db on the receiver and 9o'clock on the Triton dials?
Is there some other setting I am missing somewhere that makes the sound this loud?
Appreciate anyone who can help with ideas.

Don't use the LFE input on the Tritons, use the Speaker level inputs only...the results should be nite and day.

Unfortunately that is not the case either.
When I switch the receiver subwoofer setting to No the bass still booms out of the Tritons.
Except now there is no independent control of the sub volume since the Tritons dials are already set at their lowest point.

Are the Triton's set to Large with No crossover and sub set to none? How does it sound in Direct mode?

Are these new speakers? Because it sounds like the input level control has failed to me. This is an issue we had with the first 200 units produced (years ago), which were all (supposedly) repaired in the warehouse or in the dealers' showrooms. We haven't seen this issue since, but it sure sounds like the problem on yours. If so, you'll need a dealer to swap the input panels for you (should be a warranty repair, at least as far as the parts go). If they are new, I am at a loss as to what in your system setup could cause this and suggest you should seek support from the dealer that sold them to you.

Yes. Turning subwoofer to No automatically makes fronts fullrange.
Direct mode still sounds as boomy as everything else.