Did you ever buy too much bass?

You can't buy too much subwoofer, unless you get to the point that something physically does not fit into the space you have. You can turn down a large sub and make several types of adjustments depending on your system to make it transparent, but you can never turn up a sub that is too small and underpowered. My advice is always to buy the best and largest sub that you can afford, and then be happy for a very long time. There is no such thing as "pairing" or matching, or other old wives tales applicable here, it's about the bass. So many myths and half-truths out there about subs. A sub can both supplement and support the low end of almost any system out there, no matter how 'high end" or basic the system may be. I've had the pleasure of owning a large variety of subs since about 1986 with various systems. Everything from custom-built cabinets with separate amps, to multiple subs in my main room currently. Some that have been celebrated and some that get a lot of questionable reviews. Not once have I ever said the sub doesn't belong or that I spent too much money.  Always read the specs and performance details, as that is all that mostly matters. In-house demo would be great but is impractical or impossible for many people. The typical showroom is nothing like your house, so the specs tell you most of what you need to know, and after that it will be placement and adjustments for your space. You are not listening to a sub for the most part, and the adjustments and ability to blend into the system are what matters, which can be done with all of them. Just follow the advice to buy a highly rated, highly powered, and suitably large unit, or multiples. 

I've been using a sub woofer in my 2 channel stereo rig since the late ninities Most of my friends back then had  never heard of using a sub in a home stereo system I currently have tower speakers with built in powered subs and two SVS Ultra 13 subs with the upgraded plate amps  The subs can be controlled with the SVS app and can be tweeked from my listening position  I typically have the crossover and sub volume set on the low side and the dynamics and impact is amazing! The subs just disappear! I've used Dirac to dial everything into my room  Has anyone used the Anti mode 8033 automatic sub woofer equalizer? I've heard it works very good for sub woofer integration for little cost

Over powered rooms with booming muddy midbass is quite common. IMHO, a subwoofer is best when used literally as intended....to augment the lower octave(s) and pickup where the main woofer’s output is weak  A sub sounds best to me when it’s not featured. I set the low pass sub filter at it’s lowest setting, and set the gain so that it’s barely noticeable except on bass heavy passages. The sub shouldn’t be active when there’s no signal in the bottom octave or two.

@sgreg1 What if your amp is A/AB, the mfr recommends running main speakers  full-range, and the sub(s) are Class D? That being my situation I have the crossover at 31HZ and the sub volume below boom point. But have not experimented with a higher cross. Where is yours set?

In my experience ported subs are efficient but the sound is not as accurate as with a sealed box sub. You also want hear the bass through the air than by shaking the floor.

I really like my Dynaudio 18s which is sealed with dual opposed drivers 9in drivers - sounds very musical and reaches below 30hz. The opposed drivers have the benefit that zero ( I mean zero) vibration is transmitted via the floor. I think this is an excellent choice for small/medium room.

I find the the best test for smooth response integration is to listen to a male spoken voice  (e..g play a podcast) there should be no boominess when the voice drops through the crossover range, or shift in perceived location. At the same time time the reponse for, say, jazz bass, should be rich, uncolored  and satisfying