How do you know if you need to add a sub (without auditioning one, I mean)?


I like my speakers, I like the SQ of my system, so I'm not asking this question because I'm seeking a remedy to a deficit. I just wonder if it would sound even better with a sub. and I don't want to buy/audition anything based on mild curiosity. Also, like many of us, I don't have an unlimited budget and wouldn't care to stretch it unnecessarily.
How does anyone else decide whether to add a sub or play a pat hand?
My speakers are ATC SC40v2s. By specs, they don't go low. To my ears, the bass is much more satisfying than anything else I've listened to in my limited experience.

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If you don't try at least one sub, you will never know what you're missing. I think at least 2 subs are needed for a decent stereo, but TRY a good one that goes down to 20Hz., you'll be impressed for sure.
I just wonder if it would sound even better with a sub. 
My experience, once you listen with a properly set-up sub(s) you won’t want to listen without it anymore.  Along with losing the lower foundation of the music the soundstage utterly collapses and the involvement/enjoyability factor drops precipitously without subs.  If I’m you I’d try a pair of the new SVS SB1000 Pro subs for $950 that come with a 45-day trial (including shipping both ways), which should be plenty.  These will get you down to 20Hz, and I’d definitely get a pair rather than a single sub.  Frankly, I highly doubt you’d end up returning them.  FWIW, and best of luck. 

Hey M6, Bruce here... the reason why you have your ATC’s (your welcome by the way!).

Sooo, interesting responses. Conflicting comments here, yet all true.

You’re lucky in that everyone who answered is knowledgeable and provided excellent advice already. 
To start, you’re satisfied so theres no need to add a sub!  Just enjoy your system 😁

BUTT (yes, its a big butt)...

there is more to be had good Sir!  Add at least a pair of awesome subs (think SVS SB 2000 pro or higher or REL T7x or higher, or equivalent used.. at least 2 identical subs, 4 is better, 6 better, get the idea?)

Anywho, three elements to music.  Treble, mids and bass.  No single element is more important than the other no matter your perceived preference or musical tastes.  Bass  (its not base by the way) provides the foundation of the music and will clean up the mids and highs while expanding the soundstage, if it doesn’t drive you crazy in the pursuit therof.
Hey, Bruce. I am eternally grateful. I won’t forget you.
I was researching subs and decided that if I gathered enough extra bucks, I’d start with a used SVS PB3000 and take it from there. We have a large, cathedral ceilinged, complex room or I’d aim at something smaller. So I appreciate your right on the mark advice. You haven’t been wrong yet.
marc