GS-X mk2 Balanced Headphone Amplifier / Pre-Amplifier HeadAmp $3,299.00 Get Dynamic, Transparent Sound With the GS-X mk2 The GS-X Mk2 is HeadAmp's flagship amplifier for dynamic and planar magnetic headphones. With a circuit that has evolved and matured over a 15-year period, the GS-X Mk2 is...