Integration is always at least a possible issue with subs. Many are very flexible and easy to integrate like the REL, Vandersteen, and Hsu, but many are not.
Most subs aren't for really low bass, they are for bass from about 60 Hz and down and I've seen both really good pairing and really horrid sounding pairings.
The question of why people don't go this way more often is probably that when you buy a full range speaker, the manufacturer has already done all the integration work for you and you can bet it will be optimal. OTOH, if you are building a system on a budget, separates offer stepwise progress even if it wouldn't have cost more to just buy the full range speaker in the first place.
I listened to a pair of Spica TC-50s with Vandersteen 2Ws and it was pretty impressive, so very good sound is possible either way..
Most subs aren't for really low bass, they are for bass from about 60 Hz and down and I've seen both really good pairing and really horrid sounding pairings.
The question of why people don't go this way more often is probably that when you buy a full range speaker, the manufacturer has already done all the integration work for you and you can bet it will be optimal. OTOH, if you are building a system on a budget, separates offer stepwise progress even if it wouldn't have cost more to just buy the full range speaker in the first place.
I listened to a pair of Spica TC-50s with Vandersteen 2Ws and it was pretty impressive, so very good sound is possible either way..