Feel that? If you're an audio purist, the sensation of your wallet tingling is probably a familiar experience. This time, you have Meridian to thank, which is aiming to help you get the most from your nice headphones. The company just debuted the Explorer: a portable, USB-powered DAC and headphone amplifier that's priced at $299. Like all external DACs, the unit promises better sound quality than typical onboard solutions can deliver, and as a high-end touch, the Explorer offers asynchron
