Logitech Z407 - $157
This one can put underneath the monitor so if you are looking a speaker like soundbar can consider.
The downside is when you turn it on for the first time it will emit a test tone to check the speaker.
I can't think of any others like others who have tested other speaker.
The next up will be Klipsch promedia but that speaker is not prefect and overpriced.
Setup with subwoofer like Edifier R1280DB with T5, the subwoofer setting must be
set properly for proper bass response.
I used to own the Logitech Z625, it's bass is fantastic but the mid range is harsh and horrible.
I brought the Edifier R1280DB which is good but since it lacks a subwoofer so bass/low frequency
like rumble isn't that as good like 2.1.
So I went back and forth until I end up with Logitech Z407 which I am still using
Creative katana speaker wise I won't say too much about it since it heavily relies
on software for best sound.
I had brief experience with Creative Katana V1, take note soundbar speaker are tiny
So the sound is small which is why software tweak is required to make it sound bigger
and wider.
But of cuz you will question me what about Logitech Z407 it's speaker is also small.
The Z407 isn't designed as soundbar but a PC speaker.
It's soundstage is wide and spacious, there's no software to do any tweaking to
the speaker so just plug and play.