The most important question when upgrading audio, "What's your price range?" There are lots of options. For example: Sony SSCS5 Bookshelf Pair $100 JBL Stage

The most important question when upgrading audio, "What's your price range?" There are lots of options. For example: Sony SSCS5 Bookshelf Pair $100 JBL Stage A130 Pair $300 ELAC Debut 2.0 B6.2 Bookshelf Speakers $340 And on up! If this is what you currently own (https://www.logitech.com/assets/52567/3/z333-multimedia-speakers-setup-guide.pdf https://www.logitech.com/assets/52567/3/z333-multimedia-spea...) you're likely going to need to purchase an AMP as well to drive your new speakers. You might be able keep your current setup, remove the existing Logitech speakers, and use the L/R RCA out from your sub to the new AMP (depending on what the sub is outputting to the existing speakers) and then wire your new speakers into the new AMP (you'd need to figure out how to convert the output correctly to do this however). That should keep your handy volume control knob still functioning. That said, a simpler approach if you're willing to give up your control knob and headphone port, you can just run the input to the new AMP and then run the sub out to your z333 subwoofer. I recently picked up a Fosi Audio BT30D Bluetooth 5.0 Stereo Audio Amplifier 2.1 for my office. You won't get wall rattling volume levels with it due to the wattage output but (in my opinion) most people don't need that for a desk setup. It's not expensive ($90) and is nice and compact.