Off-receiver; subwoofer timing control options

[Ektalog]

It's a 10" subwoofer, for music, dead center at the same plane of the speakers.

For CD music, I am just fine. I allow my Denon receiver to do bass management and it allows me to adjust to 1/10 of a foot. I tuned it by ear. Sounds well integrated. This is all done in PCM.

The problem is that for SACDs, I use some tricks that allow me to keep everything in DSD > analog, including the subwoofer...but I have no timing control on the latter. Switching between modes, it is painfully clear that the DSPed PCM signal is no match for the DSD ...one until the subwoofer is involved. The tighter-defined bass as managed in PCM is much better.

The solution could be an external box that allowed me to control subwoofer distance timings with enough granularity (like the Denon does) even if the sub signal is converted to PCM in the process.

Or a good 10 inch subwoofer with such built-in abilities.

Any ideas?