“ This is a review of the Crack amp driving Sennheiser HD800s. I haven't had the chance desire to audition it with any other cans. The price is for the amp ($213) and the Speedball upgrade ($110). I've had the combo for about two years, and have several hundred hours on it. The Crack is an OTL headphone amp kit, designed for high-impedance phones. Assembly is easy, the...” --Bill Way
“This review is based on matching the Mini X with Hifiman He-500 Headphones. You may be reading this review, unsure what to make of this Amp, asking how can a cheap sub $200 amp offer the power needed for an expensive Headphone such as the Hifiman He-500? If you have done your homework you will find this is the stereo amp everybody is...” --fluidz
“The Bottlehead S.E.X. is the mid-level DIY tube headphone amp from Bottlehead USA. As per the very well-known Crack OTL amplifier, it's a kit that you build yourself, but it's a little more challenging than the Crack due to the extra components involved. In short, the Crack and S.E.X. both have their own strengths, but the S.E.X. is a definite step up in overall sound (which is a...” --Loquah
UPA-200 represents a true breakthrough in audiophile-quality amplification. At last, a truly affordable stereo power amplifier that can satisfy the most discerning aficionado, and at the same, is affordable to anyone with a desire for real quality. Our advanced engineering and design techniques have resulted in an amazing new amplifier. Its rock solid performance and affordable price point...