Brainwavz AP001 Portable Headphone Amplifier. The Brainwavz AP001 is a ultra portable headphone amplifier that is designed to help deliver more power to your headphones, earphones or other portable speakers than your standard iPod, iPhone, Smartphone or MP3 player. Using an OP Amp the AP001 is able to deliver powerful audio amplification and bass enhancement, without overly colouring or distorting the original audio signal. So buy this Brainwavz AP001 Portable Headphone Amplifier Now £25.00.