sub integration merlin tsm mme

I had an audiophile friend come over and while we were listening, we made some sub crossover adjustments that. I have an old Rel Strata III sub and was crossing over at abot 26hz and had the sub volume at about 10 and 11 o'clock. My friend said why don't we play around with the sub integration and see what happens. He listened while I adjusted. Well, we ended up between 47 and 49hz leaning towards 49hz and volume between 8 and 9 o'clock and also reversed the phase. To my ears it is much better this way. Music has more body, soundstage, depth, and the subtle nuances are more pronounced in a good way. Sometimes is it better to have 2 pair of ears as opposed to just 1 pair. Curious to where others have the crossover set. My room is 16X19X8. He said many make the mistake of having the sub crossover set to low. He felt that the rel is a great match with the TSM, very seemless and quick to keep up with the tsm's
49hz crossover point rather than 26hz seems better to me. Few monitors do much below 40-50 hz or so.

I've used my M&K sub with both Triangle Titus and Dynaudio Contour 1.3mkii.

Crossover for Triangles works best up around 50-60hz or so. For the Dyns, crossover down more towards 40 hz works best. Sub level is significantly higher also for the Triangles than the Dyns, which are capable of handling more low end in a larger room especially. The Dyns are generally accepted as extending lower and fuller into the bass as the Triangles.

Properly matched, both are absolutely top notch, with the Dyns exhibiting a touch more fuller sound and warmth. The Dyns retail for 5X that of the Triangles however. When a sub is entered into the mix properly, the differences between monitors can become a good bit more subtle.
I used a Paradigm sub with DeVore Fidelity 8 speakers. I had the sub 180 degrees out of phase with the DeVores, the crossover set at 50hz and level control around 10 o clock. It blended quite seemlessly. It took me 2 solid months of fiddleing to get to the point where I was 90% satisified. I have since sold both the sub and speakers and moved on to a true full range speaker system.
My crossover with my TSMs is set at 50hz. That is what Bobby recommended, and it has worked very well for me. Phase will be dependent upon each person's situation.
You might try something like 80 Hz to relieve your TSM of LF duty. That's still low enough that you won't localize the sub. Use an SPL meter (set to C-slow) with a white or pink noise source to match the levels of your speakers, including the sub.

It seems like your ears and Bobby's recommendation are on the same page, I would have to have an awfully good reason to not follow his recommendation, seems like you have found the sweet spot on your own.
Tzh2ly, our systems have the same model speakers, sub and are in similarly sized rooms. My REL is connected to the amp's speaker outputs using the Unbalanced Neutrik high level input. I suspect yours is as well.

In my case, after running and charting multiple series of test tone sweeps and doing hours of critical listening my REL's crossover is now set on C2 and a volume of 5.

That is, of course, 49Hz with the volume between 8 and 9 o'clock.

You may be onto something...
I used a Martin Logan Depth set to 45.

Using discretion regarding the sub's volume,(not beyond 5)it was a nice match in my large room.

I didn't fool around much with settings, just tried to augment the Merlins and not leave to large a gap between the speakers and the sub.