"By listening to the Coffman Labs H1-A, I realized that there are engineers who are truly dedicated to refining the listening experience to the highest level. The hours of work and dedication to sound from Coffman Labs are clear the moment you begin to listen. As a musician, it's inspiring to know that the music I produce can be recreated in such a convincing manner...Hearing the H1-A makes it impossible to distinguish between harmonious blend and separation between instruments, due to its ability to create a unified performance. Its remarkable affect on soundstage also contributes to the feeling of sitting in a large concert hall. I honestly had no idea that it was possible to recreate a live listening experience so closely."
-Sheldon Kreger, Headfi.org
Sheldon's words mirrored our experience almost exactly. The H1-A, (and the headphone stage in the G1-A, Coffman Labs full function preamp) is exceedingly highfalutin kit. It employs the 6C4 tube in its gain stage to drive a pair of either 50L6 or 25L6 tubes in a push pull circuit. There is a handy mini-jack input of the front of the unit as well as three rca inputs on the rear of the unit. The volume control is dead center flanked by source selection and impedance selection.