Do I need a subwoofer?

@olfac87 ,

Do you know exactly what series it is? It should be on the back.

The series 80, the first ones, didn't go that deep on the bass, they were 2db down at 37Hz (quick check) and by 20Hz would have dropped a lot. Subs would definitely help for the deep bass.

The series 2 was tuned to achieve much deeper bass. They were flat to almost 20Hz. However, the series 2 to work "properly" required the external equalizer.

I am definitely a subs person, and high pass the mains. It reduces distortion. Would that benefit the 801? It is a trade off. Using the bass of the 801 with external subs will even out the bass at the trade-off of more distortion in the 801s. A challenge and fun experiment to see what you like better. I do recommend for subs learning how to take room measurements. It is cheap and much quicker and more accurate than trying to do it by ear.

 the QLN Prestige 5s are down 3dB at 26 Hz at 1 meter which means in a normal sized room at 3 meters they are down somewhere around 10 dB. You still need subwoofers if you want to try duplicating a live performance.

That is not how it works. Every frequency is "down" at 3 meters, but depending on cancellation, room response, it could be up at 26.