Your experience of moving to two subs

Here is my take in this topic. Their is nothing wrong with one sub in a system if you implement it properly if you have the right resources. Yes dual, quad, etc, no matter how many subs you put in a room is going to improve the smoothness of the response but doing it without the use of tools and listening it not going to solve by itself especially in a room that is untreated. I have a small room where my system is and really might not require a sub but I have it for use of my listening preference, type of music, etc. My sub is set low 50s with the phase inverted. I dont have the sub in the center because I have the component rack in the area. So the sub is off center to the left about 1/4 wavelength of 1/2 of the room node, in this case around 60hz. This is almost 1/3 octave above the sub crossover frequency. The sub is low enough that localization is less noticeable and easier manageable.

REW is the norm for measurement software for this situation. I personal use Rational Acoustics for measurement in the outfield but since I have it available, it makes it easier to see what your response look like. If you are inclined with using measuring software, more power to you. Of course, you ears are the final judgement.

Does anyone have an opinion on the benefits of 2 subs vs only 1 when there’s no need for more bass oompf?

yes i have had subs for over 25 years, of various brands (hsu velodyne m-l jbl and mostly/many rels) -- the answer to your question is a resounding yes, dual subs help expand the soundstage considerably and integrate better (as each sub has lower output than the single one)

I didn’t think I would get such high quality responses here in a row! Starting with low expectations worked out well 😆 I’ve been very satisfied with the sound I’ve been getting from my Rythmik F12G in the med-large room my system is set up within, so I’ve kept putting other upgrades above getting a second one of them. But it’s helpful to get this feedback.

Thankfully, I’ve never had any difficulty integrating subs by ear using manual phase and crossover adjustments. I do have an SVS SB2000 in a different system, so I think I’ll play with trying to integrate it into my main system temporarily, just to see if I can get a general sense of this wild world of sub-bass "smoothness". I have an extra set of longer subwoofer signal cables to make it work, too.

I’m also now thinking that since my Rythmik is the one with the paper cone (vs aluminum) for faster response, and there must be more distortion involved because of the relative flimsiness of paper, that two subs working less hard would help increase clarity. Honestly, hard to imagine more sub-bass clarity than what I have now, but I’m sure it’s possible.