subwoofers and panels don't mix

I became really frustrated with trying to integrate subs with Maggie 3.5R's. About 6 months of trying with Carver true subs (they were poor, slow and had horrible overhang).
I spun them off for a brutal loss and moved on.
They literally had a delay before playing and 1-2 seconds of overhang afterwards. I guess when they glued a 4 pound hunk of steel to a passive radiator to calm it down that's what you should expect.

So I went on to smaller Velodynes (can't remember the model). Mass loading and spikes helped, but still seemed far too dissimilar to be acceptable. In either case with the Carvers or Velodynes, I tried every possible combination of electronics, internal XO and external Bryston XO, low pass/high cut frequencies, running the panels high passed and full range, different cabling, etc. None were acceptable to me.

I've heard REL subs in a few situations with Maggies and they were better, but still not great. I can say that I prefer 2 subs far more than one, regardless of location and implementation. Also, generally, that smaller the sub driver, the better luck you'll have.

I really can't believe that Harry Pearson in Absound recommended 3.6's and Carvers- shockingly bad IMHO. That would have been the point I stopped listening to reviewers as any reference other than anecdotal.

RFG

Shadorne has a great point. Another thing I found during the Maggie subwoofer debacle is that Maggies seem to be very linear in output power (or sound pressure) relative to input power from the amplifier.

Subs (and most dynamic speakers in my experience), tend to
be more logrithmic, which happens to be more like the way we hear. Not that the comparison between panels and dynamic speakers is bad, just that they are different.

That difference seems to lead to an imbalance between
panel level and sub level with different source material
and differences in recording levels and different levels in individual songs. I found myself getting driven crazy adjusting the sub volume versus panel level even within
1 song or when I changed albums. That level problem even more than the dissimilar speaker mating problem led me to give up on the process and just listen to the panels full range.

Best of luck, I hope you have better results in your quest.
An electronic crossover is helpful, but has other issues that seem to go along with it (phas and staging issues mostly).

RFG