MP4 Nation offers the Brainwavz S0 Noise-Isolating In-Ear Headphones
bundled with the Brainwavz Portable Headphone Amplifier
, model no. AP001, for $34.50
with free shipping
. (Select the amplifier from the "Free Gift" drop down menu.) That's $19 less than the best total price we could find for these purchased separately. The earphones feature a gold-plated plug, oxygen-free copper cable, 9mm dynamic drivers, 18Hz to 18kHz frequency response range, carrying case, and nine pairs of varied ear tips. The amplifier features two stereo line outs, 120mAh rechargeable battery, and powers headphones from 16 to 150 ohms.