Don't see why. The sub will outclass the soundbar and cost more but a quality sub will help with the soundbars poor bass reponse, and better subs will be able to play higher frequency better. You'll need to use a high crossover in the sub, what soundbar do you have?
DHT-S217 - Compact Sound Bar with Dolby Atmos | Denon - UK
The DHT-S217 Compact Sound Bar with Dolby Atmos from Denon provides high quality audio for your hi-fi needs. Explore more Sound Bars at Denon - UK.
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