Best Desktop Speakers under $500

Hello,
I think you should go with the PSB AM3s for $399. If you can find the AM5s used that would be your best bet. They retail for $599. They are powered and have several inputs including a phono stage. Also has Toslink, Bluetooth, and line in. And just in case you do want better bass it has subwoofer out. One and done powered speaker system.  Plus, All Paul Barton speakers are really good. I heard them at this store in the Chicagoland area:
https://holmaudio.com/
this store will let you try them before you buy them in your home. 

The Vanatoo Transparent Zeros are quite nice. Stands would be recommended to get them up off the desk.

I have the Vanatoo Transparent Zeros and for the price I don't think you can do much better.  The smaller Audioengine and Kanto powered speakers look nice but they really need a sub to help with the lower frequencies.  The Vanatoo's really have an advantage with the passive bass radiators. Highly recommend.

No love for the Elac Uni-Fi at $599?

Logitech makes some good speakers for computers check out this link https://www.logitech.com/en-us/products/speakers/z906-surround-sound-system.980-000467.html enjoy