@bigtex22 --
Still enjoying my Sonus Faber Olympica Nova Vs in our den where I mostly listen to jazz. However…I had a nostalgic experience tonight and streamed up some Def Leppard and cranked it LOUD. With this kind of rock, I am missing a little of the bass I remember from my school days. Got me thinking, how many of y’all are running a subwoofer in your stereo setup with floorstanding speakers? What do you think? Any issues with sound distortion?
Remembering an experience of played back music (or just experiences in general) can be tricky, as such recollections can be "modified" in one’s thinking back on them - not that I’m implying this in your case. Moreover, the gear used for playback back then could’ve been woefully bass-heavy and yet despite of it being perhaps less than "audiophile" inclined formed itself as a reference in your head, and as such may prove at odds with your current setup and its likely more frequency balanced qualities in reproduction.
Or, maybe the above is just a load of redundant b*llocks, and you’re simply in want of some added bass impact with named music as is, earlier references and recollections be damned. Whether a subwoofer, preferably a pair of them (or more), will address your issue or not is dependent on several factors, not least of which is how you decide to implement them.
Much if not most of the bass impact of music resides in the central/midbass area, and if you’ll run your main speakers full-range and blend in your subs fairly low (say, with a bit of overlap a low-pass set at ~40-45Hz), I’m not sure your subs will add the can kind of impact you’re looking for. Actually, I’d either blend in the subs rather low <35Hz or fairly high from 80Hz on up to stay out of the most predominant central bass region and any mixture of mains/subs here, which in your case translates into a favorable 80Hz on up subs low-pass.
This however leaves you with the need of high-passing your Sonus Faber’s, and not everyone are happy with a digital cross-over/DSP unit over their already passively configured main speakers, although I’d say with a quality digital XO the benefits of high-passing the mains (more headroom, lower distortion, likely better overall integration) will clearly outweigh any negligible influence of the DSP itself and a possible A/D to D/A conversion here. High-passing your mains from 80Hz on up necessitates a pair of subs placed symmetrically and close to each main speaker. Generally I’d avoid using a built-in high-pass filter in the subs; buy a separate, quality digital XO instead.
If for some reason the thought of high-passing your mains seems less desirable to you I’d suggest the following: experiment with the placement of your main speakers, and see if you can retrieve perhaps some midbass energy this way. Then add a pair of subs from the likes of PSA (using pro woofers and quality ICEpower amps) low-passed in the 40-50Hz vicinity and hereby overlapping your mains a bit. A pair of sealed PSA models like the S3012 with dual opposing pro 15" B&C woofers would seem a great match. Should you still lack midbass impact I’d go forward with high-passing the mains and a cross-over no lower than 80Hz with the suggested PSA subs.