Atma-Sphere S-30 MK III.1 Stereo OTL Amplifier – $3,990. Good OTL amps are just expensive to make… complexity from the power supply to the number of tubes requires drives up cost, but Ralph Karsten at Atma-Sphere has put together a great sounding hand-wired 30W/Ch OTL that cut no corners in a category where such (OTL) […]