The Original Morgan Jones Earmax

Morgan Jones, author of the book Valve Amplifiers, reverse engineered a small, portable tube headphone amplifier called the Earmax. Several individuals used Morgan's schematic to build their own headphone amplifiers and, eventually, the idea made its way to Headwize. The original Morgan Jones Earmax schematic had these valus:

The Original Morgan Jones Earmax

In the reverse engineering process Morgan was not attempting to improve on the Earmax, but there is a significant flaw in the Earmax design. This flaw is in the value of the plate resitor for the WCF output stage. It is too big.