Thomas Mayer latest tube venture project is all new Headphone Amplifier. Some of the 32 Ohms impedance headphones are a too heavy load for a preamp and this why and how the E55L single ended headphone amplifier seen the light of the day. With E55L triode in charge for the gain it was designed to drive the very sensitive Grado RS1 whith 1mW for 96dB SPL and 32 Ohms impedance…
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