RCA / Optimus 40-5037 Linaeum Ribbon Tweeter Stereo Bookshelf Speakers

The RCA 40-5037 speakers are well-regarded, compact bookshelf speakers from a partnership between RCA and Radio Shack, notable for their high-quality Linaeum ribbon tweeters and 5-inch woven Kevlar cone woofers in durable aluminum cabinets, offering surprisingly detailed highs and good bass for their size, often compared to the Optimus LX-5 series and popular for budget audio upgrades. 

Key Features & Specs:
Tweeter: Linaeum Ribbon
Woofer: 5" Woven Kevlar Cone
Enclosure: Die-cast Aluminum
Power: 75W RMS / 150W Peak
Impedance: 8 Ohms
Ported: Rear-ported (1" tuned)
Connectivity: Wired (Banana Jack compatible) 

Performance & Reputation:
Sound Quality: Praised for clear, detailed highs from the Linaeum tweeter and respectable bass from the Kevlar woofer, making them great for near-field listening.
Value: Considered excellent value, especially for DIY upgrades, as the Linaeum tweeter is a standout component.