When you say $500 each, to me that means $1000/pair. (Seems rather expensive for Sonos.) At just a little more than that price range ($1250/pair), I'd try the KEF LSX powered Bluetooth speakers. With their own built-in amp, in addition to 4.1 AptX Bluetooth, they have a direct connection and also DLNA.
If you're into near field, desktop listening, I've been happy with the Audioengine HD3+ speakers (only $350/pair). They are self-powered, have Bluetooth, direct connection, and a USB input with their own DAC. They are very smooth, perhaps excessively so. If you want crisp, and detailed, look elsewhere.
There is a good selection in between those two price extremes. I've heard Ruark recommended here. If you want great bang for the buck, check out Dayton Audio and Elac. Pioneer, Yamaha and Denon also have good speakers for less than audiophile prices.