I've been searching for a set of speakers that doesn't require a regular 3.5 mm audio jack. Made by a company called "LaCie," I found the "Bobourg USB Speakers."
First off- I took a chance with these because no place selling them clearly listed that they don't require the normal 3.5 mm input/jacks. That's part of why I'm writing this review, in case anyone else needs speakers without an audio jack. It can be a hassle to plug in 2 cords instead of 1 every time when you do it often, especially when your audio port is in the back of your PC.
I've been really pleased with these. Though I don't use the buttons on the speakers for volume, I did try them. They seem to notch up or down the volume more than expected for each press, but the speakers are heavier than expected, so they don't just push off the table when pushing the buttons (I like).
The sound sounds good to me, though I'm no audio expert. It seems to have a differentiation between left and right audio channels, which is standard, but I wasn't sure at first if it would do that since it's USB. The image on the back of the box says the digital audio is better than the analog (3.5 mm) due to no conversion loss.
One last thing, the cords connecting the separate speakers together looks like a 3.5 mm adapter and it's about 3ft long, which was better than I expected. The USB cord seems about 3 ft long too. Pretty sweet setup.
I paid around $30 for these including shipping. For the price, quality and expectations met, I give them a 5 out of 5 star rating. Good job LaCie!