Dell Home offers the Sony ZX Series Noise-Canceling Headphones in Black, model no. MDR-ZX110NC, for $34 with free 1-day shipping. That's the lowest total price we could find by $3, although most sellers charge $45 or more. They feature 12 - 22000 Hz frequency response, 10 dB/mW sensitivity, and 45 Ohm impedence. One AAA battery is required for noise-canceling playback (not included).