After looking in the direction of tube headphone amps, contacted Dennis Had(former owner and founder of Cary Audio) a few weeks back. Found that he is building headphone amps in his retirement days. Never owning any tube audio gear before now, figured his Class A tube headphone amp would be a great first start. So I asked him to build me one. Dennis was responsive and kept me in the build loop along the way. Just received my unit the other day. The packing and shipping of his product is first class. Took me longer to remove the unit's protective bubble wrap and packing material than it was installing the tubes in the sockets. My current headphone setup consists of: IHA-1 headphone amp w/ added DACT stepped attenuator and balanced input/output. Audio Alchemy DAC 3.0 w/ Power Station 4 Sony CD transport Senn HD600's w/4pin XLR balanced cable set. Short term system upgrades will include CI Audio VDA-2 DAC w/upgraded power supply running via balanced cables. After initial amp power up and warm up, grabbed the first live recording CD I could find. Loaded Fleetwood Mac The Dance to see what the amp sounded like. Power aplenty and detailed would be an understatement. Musical bliss has been found in a headphone rig. Listening to the live track "Big Love", Lindsey Buckingham's guitar work sounds amazing. Enjoying various vocal, acoustical, and electronic recordings the last two evenings and all sounding just fantastic right out of the gate. I've made more than a few audio purchases over 30 years of buying equipment. Add the IHA-1 headphone amp to a short list of purchases that have contributed significantly to my audio listening enjoyment.